Background: Dental caries is a disease which is caused by the acidic by-products of the metabolic processes of dental plaque. Silver components are one of the clinical solutions to prevent caries. This study aimed to investigate the effect of silver diamine fluoride (SDF) application on the shear bond strength of glass ionomer to primary teeth enamel. Materials and Methods: In this in vitro study, a total of 48 anterior sound primary teeth were randomly divided into four groups (n = 12). The control group (G1) consisted of healthy primary teeth, and the three experimental groups (G2–G4) were composed of demineralized primary teeth. The second group did not undergo SDF treatment, the third group underwent SDF treatment, and the fourth group underwent SDF treatment plus polishing. Glass ionomer cylinders were bonded to all specimens and subsequently tested by a universal testing machine to measure the glass ionomer shear bond strength. The type of fracture was examined by a stereomicroscope. Data analysis was carried out using the SPSS 22 statistical software. Data were analyzed by one-way analysis of variance and posthoc Tukey tests (α =0.05). Results: The mean shear bond strength of the glass ionomer was significantly higher in the control group than in the other three groups (P < 0.05). The mean shear bond strength of glass ionomer was significantly higher in the SDF-treated group than in the non-SDF treated and SDF-treated and polished groups (P < 0.05). Conclusion: Although the glass ionomer bond strength to sound enamel was higher than other groups by a significant margin, the application of SDF increases the shear bond strength of the glass ionomer to remineralized white spot enamel in primary teeth.

Background: Children with attention-deficit/hyperactivity disorder (ADHD) are more prone to tooth decay. In this regard, parents, especially their mothers, play a major role in the oral health of their children. Materials and Methods: The present study was a cross-sectional descriptive study. The population of this study was 64 children with ADHD referred to pediatric psychiatric clinics in Isfahan. Inclusion criteria include willingness to participate in research. At least 6 months has passed since their child was diagnosed with the disorder and their child is receiving treatment.Lack of obvious physical disorders, psychotic disorders, mental retardation and chronic diseases in children with attention deficit/hyperactivity disorder with the approval of a psychiatrist. Collaboration for dental examination by a dentist. Exclusion criteria include obvious physical and mental disorders in mothers of children with attention-deficit/hyperactivity disorder. Simultaneous participation in a study similar to the present study due to the possibility of errors in the results. Dissatisfaction with participating in the study and leaving the study during the study. The data collection tool was interview-questionnaire-examination. Clinical interviews were conducted using the Kiddie Schedule for Affective Disorders and Schizophrenia to confirm ADHD and rule out other psychiatric illnesses. Information on decayed, missing, and filled teeth (DMFT) of permanent teeth and dmft of deciduous teeth is recorded separately. The score of each index (D, M, F), (f, m, d) as well as the total index (DMFT), (dmft) is calculated for each person. Data were entered into SPSS software version 26 by descriptive statistical methods, one-way analysis of variance, t-test, and calculation of Spearman correlation coefficient. P < 0.05 was considered statistically significant. Results: The oral health status of children with ADHD did not show a significant relationship with the total score of attitude and knowledge of oral health behaviors of mothers (P > 0.05). The results showed a significant positive relationship between the level of knowledge of the participants and their education level (P < 0.05). Conclusion: The results revealed that mothers' knowledge and attitude about oral health and dental health of children with ADHD were generally at an undesirable level.

Background: Patients undergoing head-and-neck radiotherapy are susceptible to Candida colonization and infection. This study aimed to identify oral Candida species type (ST), colony count (CC), and oropharyngeal candidiasis (OPC) in head-and-neck cancer patients, undergoing radiotherapy, before and 2 weeks after radiation. Materials and Methods: In this quasi-experimental study, head-and-neck cancer patients undergoing radiotherapy (up to 6000 cGy) were recruited. Samples were taken before and 2 weeks after radiation therapy (RT). CC was assigned using Sabouraud dextrose agar culture medium and morphological studies were performed to confirm OPC. For identification, polymerase chain reaction–restriction fragment length polymorphism was performed. Data were analyzed using Chi-square-test and kappa coefficient. P < 0.05 was considered statistically significant. Results: Twenty-one of 33 patients were Candida positive. The detected fungal species included Candida albicans (60%), Candida tropicalis (22%), Candida glabrata (9%), and other species (9%). Following RT, OPC and CC changed significantly (P = 0.003 and P = 0.001, respectively), whereas ST did not significantly change (P = 0.081). Two new species (Candida krusei and Candida parapsilosis) were detected after the intervention. The OPC, CC, and ST changes after RT were not significantly related to malignancy site or radiation dose (P > 0.05). Conclusion: The present study showed that OPC, CC, and ST were not related to the malignancy site. Following RT, OPC and CC changed significantly, while ST showed no significant change. The radiation dose and malignancy site had no effects on the OPC, CC, or ST alterations following RT.

Background: Stresses on prosthetic crown directly influences the survival rate of implants hence it should be considered while selecting prosthetic material. The aim of the study is to evaluate stress analysis on implant, abutment and peripheral bone with change in different abutment and different crown materials by 3D finite element study. Materials and Methods: A numerical procedure based on finite element method was adopted to investigate the influence of different prosthetic materials and abutment materials on stress situation. Eight different three-dimensional (3D) models of a bone-level implant system and an abutment were created by using the standard tessellation language (STL) data of original implant components. Combinations included of abutment materials i.e., Titanium (Ti), Polyetheretherketone (PEEK), Polyetherketoneketone (PEKK), Polymer infilterated hybrid ceramic (TZI) along with different restoration materials Monolithic Zirconia (MZ) and lithium disilicate glass ceramic (IPS e-max). In each model, the implants were loaded obliquely (150 N). The stress distribution in the implant, Abutment and peripheral bone was evaluated through the von Mises stress analysis. Results: Higher stresses were found on neck of implants irrespective of abutment material and restorative material. Highest stress was found with PEEK material. The pattern of stress distribution in implant and peripheral bone was similar in all models. Conclusion: There is no difference in stresses with the change in restorative material but the change in abutment material has effect on stresses on implants.

Background: Mineral trioxide aggregate (MTA) becomes a hard mass after setting and making it difficult to remove and can cause significant problems in the retreatment process. The aim of this study was to evaluate the effect of different concentrations of hydrochloric acid (HCl) on MTA dissolution and its effect on dentin. Materials and Methods: In this in vitro study, 45 single-root premolars were selected. Artificially open apex was created in all samples with similar process. The samples were randomly divided into 4 experimental groups of 10, and a control group of 5. Four-millimeter thick apical plugs of Root MTA were placed in all samples in an orthograde manner. HCl was used at concentrations of 3.75%, 7.5%, 15%, and 22.5% (w/v) for the experimental groups and normal saline for the control group. Each sample was exposed to the desired solution for 15 min. Then, MTA retrieval and reaching the working length were attempted with k-file # 30. The times of each sample were recorded. Furthermore, after longitudinal incision of the roots with a disc, the dentin surfaces of canals were examined with a Dino-Lite microscope (×50). Results were analyzed by Shapiro–Wilk test and one-way analysis of variance tests. The level of significance P value was set at 0.05. Results: The lowest average time of reaching working length was observed with group 22.5% that was significantly lower than 15% and 7.5% concentrations (P = 0.005 and P = 0.011). Furthermore, by examining with ×50 of Dino-Lite microscope, no difference was observed on the canal walls. Conclusion: The optimum concentration of HCl was 7.5%. Furthermore, different concentrations of HCl had no significantly different effect on the dentinal canal wall using Dino-Lite microscope with ×50.

Background: Bone grafting is the primary treatment for the alveolar cleft. Due to the reduced complications by the sealant materials, this study aimed to evaluate fibrin glue's effect on the success rate of unilateral alveolar bone grafting. Materials and Methods: This study was a single-blind clinical trial performed on 20 patients with a unilateral alveolar cleft. Patients were randomly divided into groups: group A patients as a control group underwent bone grafting without fibrin glue, and in Group B, patients were grafted using fibrin glue. The subject was followed up through routine examination and the cone-beam computed tomography systems technique for up to 4 months. Paired t-test and Chi-square tests were used to analyze the data and the P < 0.05 was considered the significance threshold. Results: The mean age, gender, and cleft side distribution did not represent significant differences. Before surgery, the average alveolar cleft volume in Group A and B patients was 0.95 ± 0.25 cm³ and 0.99 ± 0.22 cm³, respectively, which was not statistically different. After the surgery procedure, the alveolar cleft volume in Group A and B patients was determined to be 0.31 ± 0.10 cm³ and 0.23 ± 0.11 cm³, which represented 66.7% ± 8.9% cm³ and 76.2 ± 11.4 cm³ bone formation, respectively, with no remarkable difference. Our examination did not reveal any necrosis and infection in both groups. However, despite no dehiscence observation in fibrin glue treatment patients, one subject showed dehiscence complication in the control group. Conclusion: According to results, fibrin glue may increase the percentage of bone volume formed and prevent dehiscence.

Background: The purpose of this study was to evaluate the effect of different surface treatments on the microshear bond strength (μSBS) of resin cement to zirconia-reinforced lithium silicate ceramic and to compare it with lithium disilicate ceramic. Materials and Methods: In this in vitro study, 80 specimens containing two glass ceramics of IPS e.max press and VITA SUPRINITY were prepared and categorized into four groups according to the surface treatments (n = 10) as Group 1 (C): no treatment (control); Group 2 (HF): etching with 9% hydrofluoric acid (HF) for 90 s followed by silane application; Group 3 (SPH): sandblasting with Al₂O₃ particles (50 μm), etching with 35% phosphoric acid for 40 s followed by application of silane and adhesive (Clearfil liner bond F); and Group 4 (SB): sandblasting with Al₂O₃ followed by silanization. Then, a resin cement (Panavia F2) was applied to the prepared ceramic surfaces. All samples were subjected to thermal aging (5000 cycles, 5–55). The μSBS test was evaluated and failure modes were recorded. Data were analyzed using the Shapiro–Wilk, two-way analysis of variance and Tukey's Honest Significant Difference post hoc tests (P < 0.05). Results: IPS e.max press samples revealed significantly higher μSBS values compared to VITA SUPRINITY (P < 0.001), in whole surface treatments. The HF group showed the highest μSBS value, followed by the SPH and SB groups, respectively (P < 0.001). Adhesive failure was recorded as a predominant failure mode. Conclusion: The adhesion performance of IPS e.max press was significantly higher than VITA SUPRINITY. The common surface treatment protocol including HF application followed by silanization was the most effective surface treatment for both glass ceramics.

Background: This study aimed to evaluate the reaction of the periapical tissue to Cold ceramic and mineral trioxide aggregate (MTA) following periapical endodontic surgery. Materials and Methods: In this experimental study, a total of 12 mandibular first, second, and third premolars of two male dogs were selected. All procedures were performed under general anesthesia. The access cavities were prepared, and the length of canals was determined. Root canal treatment was performed. A week later, periradicular surgery was performed. After osteotomy, 3 mm of the root end was cut. Then, a 3-mm cavity was created by an ultrasonic. The teeth were randomly divided into two groups (n = 12). The root-end cavities were filled with MTA in the first group and with Cold ceramic in the second group. After 4 months, the animals were scarified. Histological evaluation of the periapical tissues was performed. Data were analyzed using SPSS 22 and Chi-square test and P = 0.05. Results: The findings showed 87.5% and 58.3% cementum formation in MTA and Cold ceramic groups, respectively, indicating a significant difference (P < 0.001). In addition, the results showed 91.7% and 83.3% bone formation in MTA and Cold ceramic groups, respectively, but the difference was not statistically significant (P = 0.6). Furthermore, the findings revealed 87.5% and 58.3% periodontal ligament (PDL) formation in MTA and Cold ceramic groups, respectively (P = 0.05). Conclusion: Cold ceramic was able to induce the regeneration of cementum, bone, and PDL; hence, it can be considered as a biocompatible root-end filling material in endodontic surgery.

Background: As more recent implant biomaterials, Zirconia ceramic and glass or carbon fibre reinforced PEEK composites have been introduced. In this study, bone stress and deformation caused by titanium, carbon fiber-reinforced polyetheretherketone (CFRPEEK), and zirconia ceramic implants were compared. Materials and Methods: In this in vitro finite element analysis study, a geometric model of mandibular molar replaced with implant supported crown was generated. The study used an implant that was 5 mm diameter and 11.5 length. Three implant assemblies made of CFR- polyetheretherketone (PEEK), zirconium, and titanium were created using finite element analysis (FEM). On the implant's long axis, 150 N loads were applied both vertically and obliquely. ANSYS Workbench 18.0 and finite element software were used to compare the Von Mises stresses and deformation produced with a significance level of P < 0.05. Results: With no discernible differences, all three implant assemblies that is CFR-PEEK, titanium, and zirconia demonstrated similar stresses and deformation in bone. Conclusion: It was determined that zirconia and PEEK and reinforced with carban fibres (CFR-PEEK) can be used as titanium-free implant biomaterial substitutes.

Background: Due to the increasing prevalence of oral squamous cell carcinoma (OSCC) in Iran and especially in young people, this study aimed to identify human papillomavirus (HPV) using p16 in OSCC. Materials and Methods: In this descriptive-analytical cross-sectional study, 40 samples from the archives of the Pathology Department of Kashani Hospital were selected by a definitive diagnosis of OSCC with neck dissection. Demographic information including age, gender, location, and size of the lesion was obtained. Samples were divided into two groups based on lymph node (LN) metastasis. Immunohistochemical staining was performed for p16. Data were entered into SPSS 24 software and statistically analyzed by t-test, ANOVA, and Spearman nonparametric test. P <0.05 was statistically significant. Results: The mean age of patients was 59.7 ± 17.11 which in terms of age and gender there was no significant difference between the two groups including with and without cervical LN metastasis (P > 0.05). There was no significant difference between the two groups based on the grade of tumor, perninural invasion, tumor size and location (P > 0.05). The only significant difference between the two groups was based on lymphovascular invasion and disease stage (P < 0.05). The p16 expression also showed a significant difference between the two groups (P < 0.05). Conclusion: In OSCCs without cervical LN metastasis, a significant increase in p16 expression was observed compared to samples with cervical LNs metastasis. The presence of HPV was higher in samples with less LNs metastasis and possibly a better prognosis.

Background: The aim of this study was to investigate and compare the cytotoxicity and gene expression of Bio-C Repair, Mineral Trioxide Aggregate (MTA) HP Repair, and Biodentine on stem cells derived from exfoliated deciduous teeth. Materials and Methods: In this in vitro study MTT assay was used to assess the cellular viability at three different dilutions. The gene expression of Runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), osteocalcin [OCN], and dentin matrix protein-1 (DMP-1) was measured with real-time polymerase chain reaction after 7 days, 14 days, and 21 days of incubation. One-way analysis of variance and Bonferroni posttest were used for statistical analysis (p=o.o5). Results: After 72 h of incubation at dilution 1:4, stem cells derived from human exfoliated deciduous teeth (SHEDs) cultivated in Biodentine, followed by Bio-C Repair and MTA Repair HP reported with highest cellular viability. The highest mRNA expression of Runx2, ALP, OCN, and DMP-1 was reported in SHEDs cultured in Biodentine (after 21 days of incubation). Conclusion: Bio-C Repair and MTA HP Repair are biocompatible and capable of odontogenic differentiation similar to Biodentine when cultured in stem cells derived from exfoliated primary teeth.

Background: In endodontics, glide path creation has been extensively considered a mandatory clinical step to improve the safety and efficiency of rotary nickel–titanium instruments. The high anatomic variations in the mesiobuccal (MB) root of the maxillary molars are observed in the form of canal configuration, number, and position.The aim of this study was to evaluate the negotiability of MB canals in maxillary molars using different pathfiling systems (ProGlider, R-pilot, HyFlex electrical discharge machining [EDM], WaveOne Gold Glider, and C-Pilot). Materials and Methods: This in vitro study included 125 maxillary first molars with closed apex. Before preparation, all teeth were scanned by periapical radiograph for review of the presence of second MB (MB2) canals, without any resorption or calcification, and moderate curve of MB root canal. Subsequently, the access cavity was prepared with a Diamond Fissure Bur. Then, the samples were divided into five groups (ProGlider, R-pilot, HyFlex EDM, WaveOne Gold Glider, and C-Pilot). Certain relevant indices were recorded for analysis, such as the negotiability of the glide path file in the MB canals, file fracture rate, and negotiation speed. The level of significance P value was set at 0.05. Results: In this study, HyFlex EDM was the only path file that could not reach the full working length (WL) in some cases. The highest frequency of file fracture in the MB2 was observed with HyFlex EDM (24%); nevertheless, R-Pilot presented an intermediate fracture rate (16%), and both ProGlider and WaveOne Gold Glider were the safest files (4%) in this regard. However, there were no significant differences between the groups (P = 0.065). The lowest and the highest average time of reaching full WL was observed with WaveOne Gold Glider and HyFlex EDM; nonetheless, there was no significant difference between the four rotary groups. The average number of pecks in HyFlex EDM was significantly higher in comparison to those reported for WaveOne Gold Glider and ProGlider. Conclusion: Path files used for glide path preparation in the MB2 canals of maxillary molars should be flexible with low taper. The use of HyFlex EDM in the MB2 canals is not recommended due to its high taper.

Materials and Methods: This in vitro, experimental study evaluated 20 endocrowns, of which 10 were fabricated by 3D printing and 10 were fabricated by the conventional wax-up technique. The marginal gap was measured at 8 points under a stereomicroscope. The results were analyzed using the Shapiro–Wilk test, paired t-test, independent t-test, and one-way analysis of variance (α = 0.05). Results: The mean marginal gap was maximum at the distal point, and minimum at the buccal point for the conventionally fabricated endocrowns with an overall mean marginal gap of 99.67 ± 4.59 μm. The mean marginal gap was maximum at the mesiobuccal and minimum at the buccal point before pressing (overall mean of 103.92 ± 2.19 μm) before pressing, and maximum at the distobuccal and minimum at the mesiobuccal point after pressing (overall mean of 117.67 ± 2.87 μm). According to paired t-test, the mean marginal gap of endocrowns fabricated by 3D printing significantly increased after pressing at all 8 points and also in general, compared with before pressing (P < 0.001). Furthermore, the mean marginal gap at all points was significantly greater in endocrowns fabricated by 3D printing compared with those fabricated by the conventional method (independent t-test, P < 0.001). Conclusion: Within the limitations of this in vitro study, the results showed that endocrowns fabricated by the conventional method had significantly superior marginal fit than those fabricated by 3D printing. Background: Marginal fit is a key factor in success of prosthetic restorations. This study aimed to assess and compare the marginal fit of endocrowns fabricated by three-dimensional (3D) printing and the conventional method.

Background: These days minimally invasive micro-osteoperforation (MOPs) has accelerated orthodontic tooth movement (OTM). However, there are some conflicting reports about their various impacts; hence, the present systematic review study aimed to evaluate the effect of MOP on root resorption, pulp vitality, and the biological changes of teeth subjected to OTM. Materials and Methods: Search in electronic databases of English literature including PubMed, Scopus, Web of sciences, Cochrane, and Google scholar as well as a manual search was performed from 2013 to 2022. Most of the studies included in this article were randomized controlled trials. Results: From the total number of 321 found articles, 31 duplicated and 268 irrelevant articles were excluded regarding the defined inclusion and exclusion criteria. Consequently, 22 articles were subjected to the quality assessment process, and finally, 18 articles were selected for the review phase. Root resorption during tooth movement using the MOP approach was reported only in one study. Besides, except for two animal studies, all of the relevant included articles showed that MOPs significantly increased the expression of some inflammatory biomarkers known to recruit osteoclast precursors and increase the number of osteoclast cells. On the other hand, two animal studies showed no differences in osteoclast counts by using MOPs in comparison to their control groups, which was consequently the result of biologic variability between animal and human and also probably the small sample sizes of these two studies. Conclusion: In this systematic review, according to the adverse effects of MOP on root resorption, one study showed higher levels of root resorption among patients undergoing MOP. However, this outcome was due to the different methods used to evaluate the effect of MOPs on root resorption. Moreover, a high certainty of evidence supports that MOP causes biological changes and an elevation in cytokines, chemokines, and other biomarkers that stimulates osteoclasts differentiation which in turn accelerate OTM. There was no change in pulp vitality status based on available evidence.

Background: Dentists play an important role in caries prevention by delivering preventive care, educating patients, and buying related products; it is critical to recognize what they know and believe about caries prevention, as well as how they use caries prevention interventions. Materials and Methods: A descriptive cross-sectional study was conducted in South India between January 2021 and February 2021 to determine the dentists' knowledge, attitude, and practice of prescribing preventive strategies and remineralizing agents for caries prevention. A questionnaire including 11 self-administered, prestructured questions was made and distributed through electronic media. Chi-square test was done. The test significance value was taken as 0.05. Results: A total of 252 dental practitioners participated in the study. The majority of general dentists and specialists followed all the measures such as pit and fissure sealants, fluoride application, counseling patients about oral hygiene maintenance, and regular recall after 6 months to 1 year (P > 0.05). Fluoridated remineralization strategy was found to be the most prescribed (69%) strategy for caries prevention. A significant number of dentists think fluoridated mineralization strategies will remain prevalent (P < 0.05). Younger dentists find practicing preventive dentistry more feasible compared to dentists with greater years of experience (P < 0.05). Conclusion: Dentists across the country are well aware, have sufficient knowledge, and prescribe preventive strategies such as fluoride application, pit and fissure sealants, regular oral health checkups, and counsel the patients about the importance of oral health but there is a lack of implementation of these preventive strategies in everyday practice.

Background: Emergence of nystatin-resistant Candida albicans (C. albicans) strains has raised some concerns in the recent years. Recent scientific evidence proves that turmeric, especially curcumin, has anti-inflammatory and anti-fungal activity. The aim of this study was the investigation of the antifungal effects of curcumin against nystatin-resistant C. albicans. Materials and Methods: This in vitro, experimental study evaluated standard-strain (ATCC 16201) and 10 nystatin-resistant C. albicans strains. The antifungal activity and minimum inhibitory concentration (MIC) of curcumin were evaluated using the CLSI-M27-A3, and the MIC of curcumin was compared with that of nystatin. The results were analyzed using the one-way ANOVA. Results: The MIC of curcumin was 15.6, 32.25, 15.6, 7.8, 32.25, 15.6, 15.6, 15.6, 32.25, and 15.6 μg/mL for the 10 resistant strains and 62.5 μg/mL for the standard strain of C. albicans. Curcumin in the above-mentioned concentrations significantly inhibited the proliferation of nystatin-resistant C. albicans strains (P < 0.001). Conclusion: According to this research, it was shown that curcumin with MIC value of 7.8–32.25 μg/mL has inhibitory effects on nystatin-resistant C. albicans strains.

Background: Oral health plays a key role in people's overall health. Dental caries is the most important problem in children's oral health. Despite significant advances made in the area of oral health around the world, there is inequality in access to oral health within Iran and abroad, and this is considered a public health challenge. This study was conducted to investigate the access barriers to children's oral health services from the perspective of parents attending the health centers of Kerman, Iran. Materials and Methods: The present descriptive-analytical study was carried out, as a cross-sectional survey, on 410 parents of children living in Kerman, Iran. The data were collected by access barriers questionnaire, and then were analyzed by SPSS software using descriptive statistical methods and the multiple linear regression test. Confidence interval (CI) in this study was 95% (95% CI). Results: The most common access barrier to children's oral health was the high treatment cost. The access barriers to children's oral health services were significantly associated with parental education (P = 0.00), maternal employment (P = 0.04), supplementary insurance (P = 0.00), and family income (P = 0.01). Parental satisfaction was also significantly correlated to the child's sex (P = 0.04), supplementary insurance (P = 0.04), and number of filled teeth (P = 0.04). The mean score of parental satisfaction was 1.83 ± 0.34; within the range of 1–3 from satisfied to dissatisfied. Conclusion: The cost of dental treatment services high and there are many barriers to accessing children's oral health.

Background: Increasing antibiotic resistance to pathogenic microorganisms (Streptococci) has led scientists around the world to turn to medicinal plants. In this study, the effects of aqueous and alcoholic extracts of Zataria multiflora on the in vitro growth of Streptococcus mutans and Streptococcus sanguis have been considered and compared with 0.2% chlorhexidine mouthwash. Materials and Methods: In this in vitro study, the inhibitory growth zone was accessed by the disc diffusion method after 48 h of incubation at 37 C. To find out the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of treatments, colony counts of cultured bacteria on nutrient agar have been considered at serial dilution at 1/2-1/1024 dilution rates. An independent t-test was used to compare the antibacterial effects of extracts while the level of significance of was considered to be 5% (P < 0.05). Results: The inhibitory growth zones of aqueous and alcoholic extracts on S. mutans were 26.8 mm and 35.8 mm, respectively, whereas growth zones for S. sanguis were considered as 25.8 mm and 33.2 mm, sequentially. Comparisons showed better effects of alcohol compared to aqueous extract (P > 0.05). The MIC and MBC assessments showed the same results (P > 0.05). In all comparisons, the effects of 0.2% chlorhexidine mouthwash were significantly better than both Z. multiflora aqueous and alcoholic extracts (P > 0.05). Conclusion: The different solvents may have contributed to the better effects of an alcoholic to aqueous extract of Z. multiflora on the growth of both bacteria. These two extracts could be used for early inhibition of the growth of the planktonic phase, as well as for better oral taste after chlorhexidine applications.

Background: At present, the status of oral and maxillofacial pathology (OMFP) in the country is not properly good. This study aimed to investigate the current status and develop practical approaches to improve occupational condition of the specialty in the future from the viewpoint of the beneficiaries. Materials and Methods: This was a descriptive cross-sectional study. The participants were oral and maxillofacial pathologists of the country (200 individuals), OMFP residents (9 individuals), and final year dental students at six dentistry school of the country at 2020 (200 individuals) through multicenter design. At the first phase, the related questionnaires were developed and assessed psychometrically. Reliability of the questionnaires, internal consistency, and repeatability were computed and confirmed. At the second phase, the survey questionnaires on the current and future condition were sent electronically to the study groups. The data were analyzed using descriptive statistical tests (mean, standard deviation, percentage) and the Pearson test using SPSS. Results: At the first phase, after primary design of the study too, 23 variables with content validity ratio below 0.56 and content validity index (CVI) below 0.79 were omitted. The questionnaire for the specialists was confirmed with Cronbach's alpha of 0.75 and intraclass correlation coefficient (ICC) as 0.83, and the questionnaire for the students and the residents were confirmed with Cronbach's alpha of 0.95 and ICC of 0.80. Results of the second phase showed that score of tendency of students to select OMFP specialty to continue education was 1.58 ± 0.57 from 5. Satisfaction score of specialists on specialized activity of this specialty is 2.7 ± 1.52 from 5. The most important reason for the students to select this specialty was “interest in being faculty member,” and the “difficulty of the specialty” was the most probable reason for not selecting this specialty. The most important priority of the residents was “interest in specialty” and for the specialists was “being faculty member.” The most important reason to change attitude regarding the specialty by the specialists was mentioned as “high occupational and profession responsibility as well as low income” with the score of 1.38 ± 3.99. “Fundamental revision in the educational curriculum of the specialty” with a score of 4.60 ± 0.93 from 5 was considered as the most important revisionary approach from the viewpoint of specialists. Conclusion: At present, the main problem regarding the OMPF specialty in the country is “high number of graduates and lack of the present occupational opportunities.” Evaluation and validation of the relevant specialized departments, producing occupational opportunities, and fundamental revision in the educational curriculum to train well-powered specialists are necessary.

Background: The goal of this study is to determine the effect of different sandblasting particles and dental adhesive systems on the repair strength of dimethacrylate-based composite resins. Materials and Methods: In this in-vitro study, 96 specimens of X-trafil composite blocks were prepared and divided into eight groups (n = 12). Four groups were sandblasted with Aluminum Oxide (AL) and four other groups with Bio-Active Glass particles (BAG). A two-component silane was applied on the surface of all the samples after phosphoric acid etching and rinsing. Two groups of the sandblasted specimens were treated with Clearfil SE Bond (CSB) and the other two groups were treated with Single Bond Universal (SBU) and new composite was bonded to the prepared surfaces. Half of the specimens in each group were thermocycled. Shear force was applied to the bonded composite using a universal testing machine with a crosshead speed of 0.5 mm/min and mean shear bond strength (MSBS) was calculated (MPa). The data was analyzed using Kruskal–Wallis and Man–Whitney U-tests with the significance level of 0.05. Results: Significant differences were observed between different groups (P < 0.001). The highest and the lowest MSBS of the thermocycled samples were reported 18.88 MPa with application of AL and SBU and 11.46 MPa with the application of AL and CSB, respectively. No significant difference was observed with application of BAG particles after thermocycling. Conclusion: Effect of AL on repair shear bond strength of composite resins is affected by bonding type. Bonding type did not affect repair shear bond strength of BAG. Thermocycling reduced bond strength in all groups.

Background: The aim of this study was to assess the effect of incorporation of zinc oxide nanoparticles (ZnO-NPs) to glass-ionomer cement (GIC) (Fuji II SC, GC Corp., Tokyo, Japan) on subgingival accumulation of mutans streptococci and lactobacilli under orthodontic bands. Materials and Methods: In order to conduct this in vivo split-mouth study, 20 patients aged between 7 and 10 years who required lingual holding arch on their mandibular first molars were divided into two groups. In one group, Fuji II SC GIC was used for cementation of the right molar band, and the same cement containing 2 wt% ZnO-NPs was used for the left one. The opposite was performed for the second group while the operator was blinded to the cement types. Subgingival microbial sampling was performed 16 weeks after cementation of lingual arch. Mutans streptococci and lactobacilli colony counts were compared. Paired t-test was used to compare the two cement groups. Data were analyzed using SPSS version 21, and P ≤ 0.05 was considered statistically significant. Results: The mean colony counts of mutans streptococci, lactobacilli, and total bacterial count in Fuji II SC containing ZnO-NPs were significantly lower than the corresponding values in plain Fuji II SC group. Conclusion: Incorporation of ZnO-NPs into GIC reveals antimicrobial features against mutans streptococci and lactobacilli under orthodontic bands.

Background: This study aimed to compare the success rate of inferior alveolar nerve (IAN) anesthesia in the mandibular first molars with symptomatic irreversible pulpitis using two anesthetic solutions of prilocaine and mepivacaine. Materials and Methods: The current randomized controlled clinical trial was conducted on 100 patients in two groups (n = 50). Standard injection of IAN block (IANB) was performed using two cartridges of 3% mepivacaine plain in the first group and using two cartridges of 3% prilocaine with 0.03 IU felypressin in the second group. Fifteen minutes after injection, the patients were asked about lip anesthesia. In case of a positive answer, the tooth was isolated with a rubber dam. Success was defined as no or mild pain on the basis of the visual analog scale recording upon access cavity preparation, entry into the pulp chamber, and initial instrumentation. Data were analyzed with SPSS 17 using the Chi-square test, and P < 0.05 was set as statistically significant. Results: The patients' pain severities during the three stages were significantly different (P = 0.001, 0.0001, and 0.001, respectively). The success rate of IANB during access cavity preparation was 88% with prilocaine and 68% with mepivacaine. This rate during entry into the pulp chamber was 78% and 24%, respectively, which was 3.25 times higher with prilocaine than mepivacaine. The success rates during instrumentation were 32% and 10%, respectively, which was 3.2 times higher with prilocaine than mepivacaine. Conclusion: The success rate of IANB in the teeth with symptomatic irreversible pulpitis was higher using 3% prilocaine with felypressin than using 3% mepivacaine.

Background: Rheumatoid arthritis (RA) is one of the most common chronic inflammatory diseases. Previous studies have reported an association between stress and salivary alpha-amylase. The aim of this study was to investigate the concentration of salivary alpha-amylase in patients with RA (by elimination of stress factor). Materials and Methods: In this case–control study, we enrolled 50 patients with RA and 48 healthy patients as the control group. The perceived stress scale questionnaire was used to evaluate scores of stress in both case and control groups, and then the participants with high scores of stress were excluded from the study. Moreover, the alpha-amylase activity kit was used for the assessment of the levels of salivary alpha-amylase. In all analyses, the significance level was considered to be < 0.05. Finally, the obtained data were analyzed by SPSS22. Results: Our results indicated a high score of stress in the case group (19.42 ± 5.83 units) compared with the control group (18.02 ± 6.07 units) which was not statistically significant (P < 0.248). Moreover, we demonstrated a high salivary alpha-amylase concentration in the case group (340.65 ± 38.04 units) compared to the control group (302.62 ± 58.72 units), which was statistically significant (P < 0.001). The sensitivity and specificity of this method, at >312 alpha-amylase concentrations, were 80% and 46%, respectively. Conclusion: In general, we indicated that the alpha-amylase concentration in patients with RA is higher than the healthy controls, and can be used as a codiagnostic factor.

Background: Cleft lip (CL) and cleft palate (CP) are among the most common birth defects in the craniofacial region affected by various environmental and genetic factors. The prevalence of these abnormalities varies in races and countries. Therefore, it is a necessity to design a website to register newborns with CL ± CP in Iran. This study aimed to design a website to record the characteristics of children with CL ± CP. Materials and Methods: First, a website was designed to register the characteristics of children with CL ± CP. To evaluate the accuracy of the website, the characteristics of all children (n = 31) with CL ± CP were recorded and analyzed. Results: Due to the capability of the website to print and create reports in Excel format, the data of registered patients were analyzed. Conclusion: As CL ± CP are very common defects around the world including Iran, it is necessary to design a website to record all information about these children in Iran. Hope this website helps the public health authorities to improve program effectiveness to treat these children.

Background: An ever-increasing demand is seen for clear aligners and transparent vacuum-formed retainers. They are esthetic and convenient. However, the biomaterials used in these appliances might pose biological safety and biocompatibility threats in terms of their bisphenol-A (BPA) release, cytotoxicity, adverse effects, and estrogenic effects. Due to the controversial results and the lack of any systematic reviews in this regard, we conducted this systematic review. Materials and Methods: Web of Science, PubMed, Cochrane, Scopus, and Google Scholar as well as references of the found articles were searched (independently by 3 researchers) up to December 22, 2021, to find studies relevant to the biocompatibility of clear aligners and thermoplastic retainers. The search keywords were a combination of the following (and more): Essix, vacuum-formed aligner, thermoplastic aligner, clear aligner, Invisalign, vacuum-formed retainer, BPA release, monomer release, cytotoxicity, estrogenicity, biocompatibility, chemical properties, and oral epithelial cell. As eligibility criteria, articles in all languages would be included as long as their text could be translated clearly using online translators or by professional translators; all types of publications (article, book, and thesis) would be included if containing relevant studies and information; they should have been on clear liners or thermoplastic retainers; and they should have been on biocompatibility, safety, cytotoxicity, or estrogenicity of clear aligners or thermoplastic retainers. There were no restrictions on the type of study (randomized clinical trials, experimental in vitro studies). Studies focusing merely on the mechanical properties of clear aligners or thermoplastic retainers (without examining their chemical properties) would be excluded. The risk of bias was assessed. Results: The risk of bias was rather low. However, the methodologies of the studies were quite different. Overall, 16 articles (1 randomized clinical trial and 15 in vitro studies) were identified. The data for BPA release were reported in four articles (1 clinical trial and 3 in vitro studies). Quantitatively speaking, the amount of released BPA reported by in vitro studies was very low, if not zero. However, the BPA level was very high in the only randomized clinical trial. Many adverse effects were linked to using clear aligners or transparent retainers, including pain and soft-tissue issues such as burning, tingling, sore tongue, lip swelling, blisters, ulceration, dry mouth, periodontal problems, and even systemic problems such as difficulty in breathing. Besides these biological adverse effects, oral dysfunctions and speech difficulties and tooth damage may be associated with clear aligners and should as well be taken into consideration. Conclusion: Given the very high levels of BPA leach observed in the only clinical trial and considering other possible dangers of small traces of BPA (even at low doses) and also given the numerous adverse events linked to clear aligners or transparent retainers, it seems that safety of these appliances might be questionable and more clinical studies of biocompatibility are needed in this regard.

Background: The digital dentistry, requires materials with wo opposite properties of machining ability and also enough hardness. The main objective of this experimental study was to investigate the fabrication feasibility of the lithium metasilicate glass-ceramic in partially crystalized stated using the spark plasma sintering (SPS) method. Materials and Methods: In this study, SPS for the first time was used to fabricate primary lithium metasilicate glass-ceramic (LMGC) blocks. The raw materials were mixed and melted and then quenched in water and the resulted frits were grinded. The resulting powder was sintered by SPS at 660, 680, and 700°C. Results: Scanning Electron Microscope (SEM), X-ray diffraction (XRD), and Vicker's microhardness assay were used to evaluate the properties of samples. Statistical comparison of the obtained data was performed by ANOVA, followed by the post hoc test of Duncan. Microstructural studies by SEM and XRD showed that all samples were composed of lithium metasilicate phase in a glassy matrix. With increasing the sintering temperature, the number and size of lithium metasilicate particles increased and higher mechanical properties have been achieved. However, the sintered sample at 700°C has less processing ability than the samples sintered at 660 and 680°C. Conclusion: The optimum sintering temperature for glass frit consolidation was determined by SPS at 680°C.

Background: Different studies about the effects of mouthwashes on force reduction by elastomeric chains are reported in the literature. Hence, this review was done for the assessment of force degradation in the elastomeric chains in different mouthwash compositions. This study helps to improve the clinical performance of elastomeric chains used in orthodontics, reducing force degradation, and finally assisting clinicians in choosing better and more efficient methods for their treatments. Materials and Methods: In this review article, an extensive search was performed in the electronic databases of Cochrane Library, Web of Science, PubMed, and Scopus from the year 1990–2020. No language restriction was considered and manually investigated the reference lists of all articles related to the title. Out of 450 obtained articles, 14 in vitro studies were chosen based on the inclusion criteria, and their quality was assessed using modified CONSORT. This systematic review was limited and written based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Results: Based on the results achieved, mouthwashes containing alcohol caused considerable force degradation in the elastomeric chains compared to the alcohol-free ones and mouthwashes with fluoride caused lesser force degradation compared to other types.

Background: Biodegradable hydrogel scaffold is one of the crucial characteristics that determine the success of pulp regeneration. The degradation should be suitable for the growth of new tissue establishment. The aim of this study is to synthesize and compare the novel biodegradable hydrogel scaffold based on hydroxyapatite (HAp) eggshell, collagen, and epigallocatechin-3-gallate (HAp-Col-EGCG) with different HAp concentrations in vitro. Materials and Methods: This study is original research. HAp-Col-EGCG hydrogel scaffolds were prepared using 1:1, 1:2, and 1:4 ratios of collagen and HAp with 10 μmol/L EGCG. The samples were freeze-dried and immersed in phosphate buffer saline containing lysozyme enzyme. The dried samples were weighed to determine the percentage of biodegradation value (P < 0.05). Results: The result showed HAp-Col-EGCG was biodegradable but it has not been concluded that it can be completely eliminated. The data were analyzed by one-way analysis of variance and it indicated significant differences in percentage values. Conclusion: Hydrogel scaffold based on HAp-Col-EGCG can be degraded and have the potential to be used as a biodegradable scaffold in supporting tissue regeneration.

Background: Polymethyl methacrylate resin is widely used in orthodontic treatments. Graphene oxide (GO) has reactive functional groups on its surface that facilitate binding to various materials such as polymers, biomolecules, DNA, and proteins. This study aimed to investigate the impact of adding functionalized GO nanosheets on the physical, mechanical, cytotoxicity, and anti-biofilm properties of acrylic resin. Materials and Methods: In this experimental study, fifty samples (for each test) were divided into groups of 10, in the form of acrylic resin discs with concentrations of 0, 0.25, 0.5, 1, and 2 weight percentage (wt%) of functionalized GO nanosheets and also the control group. Samples were evaluated in terms of physical properties (surface hardness, surface roughness, compressive strength, fracture toughness, and flexural strength), anti-biofilm properties (On four groups of micro-organisms, including Streptococcus mutans, Streptococcus sanguis, Staphylococcus aureus, and Candida albicans), and cytotoxicity. Data were analyzed using SPSS software version 22, descriptive statistics, one-way analysis of variance test, and Tukey post hoc test. The significance level was considered P < 0.05. Results: No significant difference was observed between the different groups with weight percentages of 0.25, 0.5, 1, and 2% nano GO (nGO) and the control group (without nGO) in terms of surface roughness and toughness. However, compressive strength, three-point flexural strength, and surface hardness showed significant differences between the groups. Furthermore, the degree of cytotoxicity increased by increasing the weight percentage of nano-GO. Conclusion: The addition of functionalized nGO in appropriate concentrations to polymethyl methacrylate can improve the anti-bacterial and anti-fungal biofilm properties without changing or increasing their physical and mechanical properties.

Background: The prevalence of oral squamous cell carcinoma (OSCC) has increased in recent years. With the development of various treatments, the mortality rate has decreased and more people are living with the consequences of the disease and its treatment, which can have a great impact on the quality of life. Some questionnaires measure the impact of the disease on daily activities and patient behavior. In this study, the oral health-related quality of life (OHRQOL) was assessed through the Oral Health Impact Profile (OHIP)-14 questionnaire between the OSCC patient and control groups. Materials and Methods: In this cross-sectional study, the OHIP-14 questionnaire was given to 51 OSCC patients who had completed the treatment at least 6 months before participating in this study and 51 healthy individuals, and we used the Chi-square test, independent sample t-test, one-way ANOVA, and linear regression in three models. P = 0.05 was considered statistically significant. Results: The mean age of patients was 55.86 ± 15.04 years and the control group was 54.96 ± 14.08 years. Women made up 51% of patients. The mean OHIP score was 22.84 ± 11.42 in the patient group and 17.92 ± 9.23 in the control group, which indicates a significant (P = 0.005) difference between the two groups according to the independent sample t-test. Conclusion: The OHRQOL of patients has significantly decreased compared to the control group. Surgery had the lowest quality reduction, and combined surgical treatment with radiotherapy and chemotherapy had the highest reduction in the OHRQOL. It is recommended to have regular follow-up sessions and to have a proper diet during and after treatment.

Background: Surface smoothness considered to be a significant part of the appearance and success of the restorative materials. The aim of this study was to assess the influence of four different polishing systems on surface roughness of four resin composite materials when subjected to thermocycling. Materials and Methods: This research was designed as a comparative study. Four resin composites were used which are: Nanofill composite (Filtek Supreme XT), nanohybrid composite (Tetric EvoCeram), microfill composite (Renamel Microfill), and microhybrid composite (Filtek Z250). Sixty disk-shaped specimens of each resin composite were prepared then divided into four groups according to the polishing system (n = 15); which were Sof-Lex Spiral, Diatech Shapeguard, Venus Supra, and Astropol. The specimens of each group were polished following the manufactures' instructions, then surface roughness, R_a values in μm were measured initially and after the specimens subjected to thermal cycling. The influence of resin composites, polishing systems, thermocycling, and their interaction effects on surface roughness (R_a mean values) was statistically analyzed mainly by using the repeated measures two-way analysis of variance test, whereas the Bonferroni''s post hoc test was applied for pair-wise comparisons. P ≤ 0.05 was used as the significant level. Results: The results of this study revealed that Filtek Supreme XT recorded significantly the lowest mean surface roughness (R_a) of 0.2533 ± 0.073 μm (P < 0.001). The Sof-Lex Spiral polishing system revealed significantly the lowest mean surface roughness (Ra) of 0.2734 ± 0.0903 μm (P = 0.004). Regardless of composite type and polishing system, there was a statistically significant increase in mean surface roughness values (R_a) in μm after thermocycling (0.2251 ± 0.0496 μm and 0.3506 ± 0.0868 μm, respectively) (P < 0.001). Conclusion: Resin composite type, polishing method, and thermocycling aging significantly affected the surface roughness of composites; Nanofill composite and Sof-Lex Spiral polishing system provided the lowest values of surface roughness which increased after thermocycling.

Transplantation of one tooth to another site in the same individual can be considered an attractive alternative to dental implants or fixed prostheses. This study reports the treatment results of a 16-year-old female with severe crowding in upper and lower arches and a fractured mandibular premolar with a poor prognosis. The crowding of the lower left quadrant was relieved by the extraction of the first premolar. This extracted tooth with a complete root was transplanted to the right quadrant with the fractured tooth. Platelet-rich fibrin can stimulate and accelerate periodontal healing. The platelet concentrate of this patient was prepared and applied to the socket wall at the time of surgery. The acceptable occlusion and the excellent 4-year prognosis of the transplanted tooth are presented.

Background: Occlusal loading of osseointegrated implants is believed to be an essential determining factor in the long-term success of an implant treatment. Numerous studies have been conducted on the evaluation of stress distribution by definitive restoration materials for Implant-supported fixed prosthesis, but very few have evaluated provisional restoration materials for the same. This study aims to evaluate the influence of provisional restoration material – Milled Polymethylmethacrylate (PMMA) and Milled Polyetheretherketone (PEEK), over stress distribution on the peri-implant bone around an implant-supported three-unit, fixed dental prosthesis using finite element analysis method. Materials and Methods: Three-dimensional models of a pair of bone-level implant system and titanium base abutments were created using the standard tessellation language data of original implant components. A bone block representing the mandibular posterior area was created, and the implants were placed in the bone block with 100% osseointegration in the 2nd premolar to 2nd molar region. A superstructure of an implant-supported 3-unit bridge was modeled on top of the abutments, each crown to be 8 mm in height and with an outer diameter of 6 mm in 2^nd premolar region and 10 mm in 1^st molar and 2^nd molar region. Two different models were created according to combinations of provisional restoration materials, namely, Milled PMMA and Milled PEEK based on. In each model, the implants were loaded vertically (300 N) and obliquely (150 N at 30°). The stress distribution in the cortical bone, cancellous bone, and implant was evaluated through the von Mises stress analysis. Results: The results showed no difference in stress distribution due to the different provisional restorations – Milled PMMA and Milled PEEK. In addition, the vertical load resulted in higher stress values in the implant components, cortical bone, and cancellous bone in both PEEK and PMMA models as compared to oblique loading. Conclusion: The new polymer, PEEK was seen to provide comparable stress generation in the current study without exceeding the physiological limits of peri-implant bone. Thus, it can be considered as a good alternative to PMMA resin as a provisional crown material since it provides certain additional benefits.

Background: The burden of oral diseases is increasing, which constitute a major public health problem. The use of probiotics as an adjuvant, along with routine dental care practice by an individual, can produce additional benefits in the maintenance of one's oral health. The study aimed to investigate the effect of Bifidobacterium as a probiotic on oral health. Material and Methods: Six databases and registers were searched from the start of the database to December 2021 without any restrictions. Randomized controlled trials (RCTs) evaluating the clinical effects of Bifidobacterium as a probiotic on oral health were included in the study. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed to conduct this systematic review. The included studies were analyzed for the risk of bias using the Cochrane risk-of-bias tool for randomized trial (RoB 2) tool as well as quality of available evidence using GRADE criteria. Results: From the 22 qualified studies, four studies showed non-significant results. There was a high risk of bias in 13 studies and some concerns of bias in nine studies. No adverse effects were reported, and the quality of available evidence was moderate. Conclusion: The effect of Bifidobacterium on oral health is questionable. Further high-quality RCTs are required on the clinical effects of bifidobacteria and also the optimum level of probiotic needed, and ideal mode of administration to provide oral health benefits. Furthermore, synergistic effects of the combined use of various strains of probiotics need to be studied.

Root perforation may occur at any stage of endodontic treatment and is mostly due to iatrogenic injury and may compromise the outcome of endodontic treatment. Repairing a perforation is difficult and the prognosis depends on various factors such as time, site and size of perforation, and the patient's overall health status. Hence, choosing the most appropriate material can be critical for the dentist. In this case report of a strip-perforation repair, an mineral trioxide aggregate-like material (cold ceramic) that has been shown in previous studies to have favorable properties, was successfully used.

Background: Dentistry practice has become more complex and challenging in the recent years. The clinical decision-making process has experienced many problems due to changing socioeconomic patterns, knowledgeable patients, rapid technological advances, and information explosion. The present study reviewed the status of the attitude toward evidence-based dentistry (EBD) among dental students of Iran Universities. The effect of the educational intervention was also assessed. Materials and Methods: This systematic review was conducted according to the Preferred Reporting Items for Systematic review and Meta-Analysis checklist. Search strategy was developed by Medical Subject Headings terms and keywords surfing electronic available databases including Medline/PubMed and Google Scholar and local databases such as Scientific Information Database (SID) and Magiran. Two reviewers read the abstracts of all eligible papers and excluded the duplicates. They extracted the information of the full-text of the studies included in the review and assessed the quality by Joanna Briggs Institute critical appraisal checklist. Results: Ten studies including 8 cross-sectional and 2 interventional studies met the criteria. The assessment of the attitude of 937 dental students from a different region of the country toward EBD showed moderate to acceptable status using 3 different tools. In regard to educational interventions, 2 studies were successful to improve their attitude. Conclusion: Although the researchers presented good scores on the attitude questionnaires, the quality of the study tools, the eligible criteria for recruiting the participants and the method of evaluating the construct of attitude should be investigated in future studies.

Background: This in vitro study aimed to compare the fracture resistance of fiber post and reversed-oriented metal post in the restoration of severely decayed primary incisors. Materials and Methods: In this in vitro study, forty extracted human primary incisors were sectioned horizontally 1 mm above the CEJ and randomly divided into four groups – Group 1: Central incisors restored with reverse-oriented metal post, Group 2: Lateral incisors restored with reverse-oriented metal post, Group 3: Central incisors restored with fiber post, and Group 4: Lateral incisors restored with fiber post. The coronary portion of the teeth was then restored with nanohybrid universal composite. The fracture resistance was measured using universal testing machine. The type of fracture was determined by employing a stereomicroscope. Data were analyzed using two-way ANOVA test. The level of significance was considered at P < 0.05. Results: The mean fracture resistance of glass fiber posts (208.00 ± 73.19) was higher than the reverse-oriented metal posts (190.37 ± 56.36); however, there was no significant difference between any of the groups (P = 0.353). Conclusion: Within the limitations of this study, it can be concluded that both types of posts studied in the present research can be successfully used in the restoration of severely damaged primary incisors.

Background: The aim of this study was to investigate the effect of bleaching agent, sodium ascorbate as an antioxidant, and delay time on the shear bond strength (SBS) of orthodontic brackets to enamel using Transbond XT and universal adhesive. Materials and Methods: In this in vitro experimental study, 80 extracted maxillary premolars without any defect or decay were randomly divided into eight groups of 1: no bleaching + Transbond XT (NB/TX) bonding agent, 2: no bleaching + All-Bond Universal (NB/AB), 3: bleaching + Transbond XT (B/TX), 4: bleaching + All-Bond Universal (B/AB), 5: bleaching + sodium ascorbate + Transbond XT (B/SA/TX), 6: bleaching + sodium ascorbate + All-Bond Universal (B/SA/AB), 7: bleaching + Transbond XT after a 3-week delay (B/3W/TX), and 8: bleaching + All-Bond Universal after a 3-week delay (B/3W/AB). After thermocycling (1000 cycles, 5–55°C), the SBS was measured, and the adhesive remnant index scores were determined to assess the failure mode. Data were analyzed by one-way analysis of variance, Tamhane's post hoc test, Kruskal–Wallis, and Mann–Whitney U-test at the significance level of P < 0.05. Results: The mean SBS range was 5.5–29.78 MPa. The highest SBS values were related to Group 2 (NB/AB) which were significantly higher than all groups (P < 0.05) and the lowest values were observed in Group 5 (B/SA/TX) which were significantly lower than all groups except Group 3 (B/TX) (P < 0.05). Conclusion: Bleaching with 40% hydrogen peroxide significantly decreased the SBS of orthodontic brackets, and 10% sodium ascorbate could not reverse the adverse effect of bleaching on SBS. Delaying the bonding procedure by 3 weeks using Universal adhesive considerably decreased the adverse effect of bleaching on SBS and increased the SBS to a clinically acceptable level for orthodontic treatment.

Background: Panoramic radiography is a standard diagnostic imaging method for dentists. However, it is challenging to detect mandibular trauma and fractures in panoramic radiographs due to the superimposed facial skeleton structures. The objective of this study was to develop a deep learning algorithm that is capable of detecting mandibular fractures and trauma automatically and compare its performance with general dentists. Materials and Methods: This is a retrospective diagnostic test accuracy study. This study used a two-stage deep learning framework. To train the model, 190 panoramic images were collected from four different sources. The mandible was first segmented using a U-net model. Then, to detect fractures, a model named Faster region-based convolutional neural network was applied. In the end, a comparison was made between the accuracy, specificity, and sensitivity of artificial intelligence and general dentists in trauma diagnosis. Results: The mAP50 and mAP75 for object detection were 98.66% and 57.90%, respectively. The classification accuracy of the model was 91.67%. The sensitivity and specificity of the model were 100% and 83.33%, respectively. On the other hand, human-level diagnostic accuracy, sensitivity, and specificity were 87.22 ± 8.91, 82.22 ± 16.39, and 92.22 ± 6.33, respectively. Conclusion: Our framework can provide a level of performance better than general dentists when it comes to diagnosing trauma or fractures.

Background: The aim of this study was to compare the clinical, histological, and histomorphometrical outcomes of CenoBone^® allograft with and without plasma rich in growth factor (PRGF) for the preservation of edentulous ridge in the dental sockets. Materials and Methods: This study is experimental clinical trial that 14 dental sockets were included the sockets required ridge preservation followed by implant placement in the premolar and molar of the mandible. After extraction of the teeth, the CenoBone^® allograft and PRGF were used in the test group and CenoBone^® allograft was used alone in the control group. During the first stage of surgery and 5 months later, in the second stage of surgery (implant placement), the vertical changes of the ridge were measured. Furthermore, using Core-Biopsy in the second stage of surgery, criteria of histologic and histomorphometric were determined. Data were analyzed with t-test, Mann–Whitney U-test, and Fisher's exact test at the level of significance of P < 0.05. Results: The mean trabecular thickness in the test group (52.18 ± 5.53) was significantly higher than that in the control group (41.53 ± 10.40) (P = 0.344). However, there were no significant differences in the mean values of vertical bone absorption, bone percentage, remaining biomaterials, inflammation, and blood vessels between the two groups. There was no case of foreign body reaction and the bone was vital in all the cases and in direct contact with the biomaterial. Conclusion: Although CenoBone^® allograft with PRGF was effective in some histomorphometric factors such as trabecular thickness, it did not lead to significant clinical changes.

Background: During the orthodontic bonding process, the need for repositioning or rebonding of orthodontic brackets on the enamel surface occurs frequently. The aim of this study is to compare the shear bond strength (SBS) in rebonding orthodontic stainless steel brackets with three different methods of enamel surface conditioning methods. Materials and Methods: In this in vitro study, 80 human premolars that were extracted for orthodontic purposes were randomly divided into four groups and underwent orthodontic bonding procedure (N = 20). Except for the control group, three other groups underwent debonding and rebonding process in which after removing the remaining adhesive with tungsten-carbide bur, enamel surface conditioned by three different methods including re-etching with phosphoric acid, sandblasting + acid etching, and Erbium-doped Yttrium–Aluminum–Garnet laser. Then, the SBS of the bracket to the enamel surface was compared between different groups. Scanning Electron microscopy images were also obtained from a number of samples. Statistical analysis was performed by Kruskal–Wallis and Mann–Whitney tests. Results: The highest SBS was observed in the primary bond (control group) with an average of 29,440 MPa. There was a significant difference between the studied groups (P < 0.001) and only the group that was re-etched with phosphoric acid had no significant difference with the control group (P = 0.708) ∝ =0.05. Conclusion: Rebonding of brackets using phosphoric acid for reconditioning of the enamel surface creates bond strength comparable to the primary bond. Other groups had significantly lower SBS than the control group.

Background: This study aimed to assess the effect of laser irradiation and Tooth Mousse on tooth hypersensitivity (TH) after office bleaching (OB). Materials and Methods: This clinical trial, parallel-design split-mouth nonrandomized was conducted on 30 patients requiring OB. After scaling and fabrication of a custom tray, 35% hydrogen peroxide was applied on all teeth, and 940 nm diode laser (10 W, Class IV, 110–240 V) was irradiated to the upper and lower right quadrants. Laser in off mode was used for the left quadrants. Bleaching agent was then reapplied. After completion of bleaching, a custom tray containing tooth Mousse was placed on the maxillary arch while the tray was used without the paste for the mandibular arch. A visual analog scale was used to assess the degree of TH at 15 min and 24 h after OB. Data were compared using t-test, paired t-test, and analysis of variance. Significance level was set at α = 0.05. Results: Comparison of TH at 15 min and 24 h after OB showed a significantly lower TH score in the left upper quadrant (tooth Mousse alone) than right upper quadrant (both laser and Tooth Mousse) (P < 0.05). The TH score in the right upper quadrant was significantly lower than that in the right lower quadrant (laser only) (P < 0.05). The mean TH score in the left upper quadrant was insignificantly lower than that in the left lower quadrant (no intervention) (P > 0.05). Conclusion: The use of 940 nm diode laser for OB increases the postoperative TH. The application of Tooth Mousse can effectively decrease TH after OB with/without laser irradiation.

Background: Bonded composites may increase bacterial accumulation and caries formation risk. Therefore, assessment of methods to decrease bacterial activity around them would be valuable. The literature on the efficacy of adding silver nanoparticles to fiber-reinforced composite (FRC) or adding them to bonding agents in terms of their antibacterial activity and/or shear bond strength (SBS) is scarce. Thus, we aimed to assess the antibacterial activity of flowable composites and bonding agents containing various percentages of experimental silver nanoparticles (nanosilver) against S. mutans and to evaluate the SBS of FRC and bonding agents containing different amounts of nanosilver to enamel. Materials and Methods: In this preliminary study, 0% (control), 0.5%, 1%, 2.5%, and 5% nanosilver were added to flowable composite and bonding agent. Syntheses of nanosilver and nanosilver-incorporated composite specimens were approved using X-ray diffraction spectroscopy and scanning electron microscopy. Antibacterial effects of the produced materials on S. mutans were evaluated by colony count with serial dilution method (n = 7 groups × 10 [n = 70] specimens) and agar disc diffusion test (n = 6 groups × 5 [n = 30] composite specimens + n = 6 groups × 5 [n = 30] light-cured bonding + n = 6 groups × 5 [n = 30] uncured bonding) against negative control and cefotaxime antibiotic. Moreover, SBS values of various FRC blocks bonded to enamel using various bonding agents were measured (n = 9 groups × 6 [n = 54] human premolars). Data were analyzed using Kruskal–Wallis, Dunn, two-way analysis of variance, and Tukey's tests (α = 0.05). Results: Composite discs containing all concentrations of nanosilver reduced S. mutans colony counts (P < 0.05); bacterial growth was ceased at samples containing 2.5% and 5% of nanosilver. The reduction in the SBS of FRCs was significant only for 5% nanosilver (P < 0.05). Conclusion: Adding 0.5%, 1%, and 2.5% nanosilver to composite and 0.5% or 1% nanosilver to bonding agent led to a significant antibacterial behavior against S. mutans while not significantly affecting the SBS of FRC.

Background: The temporary cement remaining inside the dental prosthesis can act as a source of microbial colonization and contamination and decrease the final cement retention. Consequently, complete removal of temporary cement before permanent cementation is suggested. This study aimed to assess the effect of different cleaning methods for removing temporary cement on the tensile bond force (TBF) of permanently cemented implant-supported zirconia copings. Materials and Methods: In this in vitro study fifty titanium abutments were screwed onto 50 analogs with 30 Ncm torque into in acrylic resin blocks. Each abutment was scanned separately, and 50 zirconia copings were designed and milled. Permanent resin cement was used to cement copings of control group (N = 10). Copings were divided into two temporary cementation types that in each group, two cleansing methods were used: Temp-S (temporary cement with eugenol and sandblasted after debonding), Samples of the control group were placed in the universal testing machine, and the TBF values were recorded. Samples of the test groups after debonding and cleaning the abutments were subjected to cement with permanent resin cement, aging, and removing. Levene test, two-way analysis of variance (ANOVA), and Tamhane post hoc tests were applied. α = 0.05. Results: The highest and lowest TBF values were found for the TempNE-SU (554.7 ± 31.5 N) and Temp-S (492.2 ± 48 N) groups, respectively. The two groups of isopropyl alcohol baths in ultrasonics in combination with sandblasting showed statistically higher TBF values than the other two groups that used only sandblasting (P < 0.001) and had similar values compared to the control group. Conclusion: Sandblasting combined with immersion in an ultrasonic bath containing isopropyl alcohol resulted in statistically similar values to the values of cementation with resin cement from the beginning. However, cleaning the inside of the copings only by sandblasting method reduced the values of the final retention force in comparison to cement with permanent resin cement from the beginning.

Background: The use of a rubber dam is more important than ever in today's COVID-19 era to limit cross infections. In children, the placement of the metal clamp to retain the rubber dam is perceived to be painful and often requiring a local anesthetic injection. This dissuades many clinicians from placing the rubber dam. Hence, this study evaluated the pain response of children to a SoftClamp^™ compared to the conventional metal clamp. Materials and Methods: This was a randomized controlled, equal allocation ratio, split-mouth clinical trial. Forty-two children aged between 8 and 12 years, having two permanent mandibular molars in need of sealants, were divided into Groups A and B (metal clamp and SoftClamp^™, respectively). The pain response was recorded using both an objective and a subjective scale i.e., the Faces Legs Activity Cry Consolability (FLACC) scale and the Wong Baker Faces Pain Rating Scale (WBFPRS). The level of significance was set at 5% (P < 0.05). The pain response recorded from the WBFPRS and the FLACC scale for the metal and the SoftClamp^™ were analyzed using the Wilcoxon signed rank test. The difference in pain response between genders and between two age groups (below and above 10 years of age) was analyzed using the Mann–Whitney U-test. Results: The children reported mild discomfort to clamp placement in both the scales. The P values for the FLACC and WBFPRS scores comparing the pain response to the metal and SoftClamp^™ were 0.311 and 0.149, respectively. Conclusion: There was no significant difference in the pain response of children to both the clamps. Good rubber dam application practices in children through the use of behavior guidance and a proper topical anesthesia technique may play a far more important role regardless of the clamp used. But the SoftClamp^™, with its more child friendly appearance could be a viable alternative to the metal clamp in children.

Background: The demand for an ideal root canal filling material in primary teeth with maximum antibacterial properties keeps escalating to improve the success rate of root canal treatment in primary teeth. Hence, the present study was conducted to determine the antimicrobial efficacy of the different concentrations of a novel root canal filling material. Materials and Methods: An in vitro study was designed to compare the antimicrobial efficacy of different concentrations of the novel obturating material for primary teeth. Different concentrations of the novel obturating material were prepared using calcium hydroxide, zinc oxide cement, and metronidazole and were tested for its antimicrobial efficacy against Streptococcus mutans and Enterococcus faecalis using Mueller–Hinton Agar for 24 h at 37°C. The zone of inhibition was measured in millimeters after 24 h. The values were entered into a Microsoft Excel spreadsheet and subjected to statistical analysis. Descriptive statistics were used for data summarization and presentation. Friedman test and Kruskal–Wallis test were used to compare the different concentrations of the novel obturating materials against S. mutans and E. faecalis. P < 0.05 was considered to be significant. Results: Against S. mutans at 1% concentration, the zone of inhibition was statistically greater at 50 μl and at 2% and 3%, the zone of inhibition was greater at 100 μl. Similarly, against E. faecalis, the zone of inhibition was statistically greater at 100 μl at 2% and no significant difference was noted at 1% and 3%. Comparison between the groups at 25, 50, and 100 μl shows no significant difference against S. mutans between 1%, 2%, and 3% of 60–40 concentration. However, 3% 60–40 concentration at 50 μl shows significantly increased zone of inhibition against E. faecalis. Conclusion: Two percentage metronidazole at 60–40 (calcium hydroxide–zinc oxide) concentration of the novel obturating material at 100 μl has better antibacterial properties against both S. mutans and E. faecalis.

Background: The present study was conducted to develop a standard questionnaire to assess the knowledge and practice of prosthodontists regarding the diagnosis and treatment of obstructive sleep apnea syndrome (OSA). Materials and Methods: This study had questionnaire designing and cross-sectional-descriptive phases. Questionnaire domains were identified by a panel of eight experts. The face and content validity of the questionnaire was assessed by experts and four laypeople. The internal consistency reliability of the questionnaire was checked using Cronbach's alpha coefficient. Moreover, its stability was tested using the test–retest method. The questionnaire was completed online by 282 Iranian prosthodontists and the relationship between different variables and scores of knowledge and practice of them with simple and multiple linear regression tests was were analyzed. Results: A 32-item questionnaire was designed. The Scale Content Validity Index was >0.8 for clarity, simplicity, and necessity in all domains and the content validity of all questions was above 0.8. As for reliability, Cronbach's alpha coefficient was above 0.7 on average. Faculty members had more knowledge (P = 0.04) and better practice (P = 0.001) compared to others. Prosthodontists who participated in sleep disorders training courses had higher scores in knowledge (P = 0.001) and practice (P = 0.001). Prosthodontists who referred patients to sleep disorders clinics had higher knowledge (P = 0.001) and practice (P = 0.001) than those who did not. Conclusion: The questionnaire developed in this study can be considered a comprehensive and executable scale with appropriate reliability and validity. There is a positive relationship between being exposed to information and the level of knowledge and practice of prosthodontists about OSA.

Background: Minimally invasive techniques should be employed to maintain pulp vitality without affecting physiological tooth resorption for pediatric patients. This study aims to evaluate clinical and radiographic success of light cure calcium silicate and resin-modified glass ionomer (RMGI) as indirect pulp-capping agent in primary molars in children between 5 and 9 years. Materials and Methods: In this randomized clinical trial study, 40 primary molars with the International Caries Detection and Assessment System criteria 4–6 score were divided randomly into two groups after computerized randomization method. After caries excavation by minimally invasive dentistry principle, affected dentin was lined by either light cure calcium silicate (Group I) or RMGI (Group II) liner followed by composite restoration. Clinical success was determined with the absence of symptoms and bitewing radiographs were taken at baseline, 3, and 6 months' interval to measure increase in dentin increment using ImageJ software. Statistical analysis for intergroup comparison was done using Paired t-test, and Independent t-test was used for intragroup comparison. The level of statistical significance was set at P < 0.05. Results: Change in dentin increment seen from baseline to 6 months in Group I was 0.19 mm and in Group II was 0.20 mm (P = 0.924). Intragroup increment was statistically significant during all follow-up intervals for both the groups (Group I – P ≤ 0.001, Group II – P = 0.009). For baseline remaining dentin thickness >1.5 mm, statistically significant increase was observed in the dentin increment at 3 months' interval between both the groups. Conclusion: Both TheraCal LC and Vitrebond show acceptable clinical and radiographic results when used in primary molars as indirect pulp treatment agents. Both the liners are equivalent to each other in terms of feasibility and cost-effectiveness but TheraCal LC can be preferred due to better handling and avoiding the manipulation step thereby reducing treatment time.

Background: Pain following surgical removal of impacted molars has remained a principal concern among practitioners. Since green tea has anti-inflammatory and anti-bacterial properties, the current study aimed to evaluate the efficacy of green tea extract local application in controlling postoperative pain following surgical extraction of the impacted mandibular third molar teeth. Materials and Methods: In a double-blinded randomized controlled trial study with a split-mouth design, 32 patients underwent bilateral removal of impacted third molars in a 2-month time interval; afterward, the sterile gauzes impregnated with green tea extract and saline were applied randomly to the surgical sites. Postoperative pain was evaluated 6, 12, 24, and 48 h after surgery using a questionnaire based on the Visual Analog Scale (VAS) and the number of analgesics used after surgery. Data were subjected to exact and Chi-square tests with the significance level set at 0.05. Results: There was a decrease in the mean scores of the VAS and the mean number of analgesic consumptions in the first 2 days after surgery. Chi-square test results showed a significant reduction in the VAS scores after applying the green tea extract only 6 and 12 h after surgery (P < 0.05). Moreover, the number of analgesic consumptions was significantly lower in the green tea group compared to the control group. Conclusion: Green tea extract may be an appropriate and safe choice for postoperative pain control after surgical extraction of the impacted mandibular third molar teeth.

Background: Xenogeneic grafts have gained attention due to advantages in compare of autografts. This study aimed to compare Xeno (ostrich) Acellular Dermal Matrix (XADM) with the free gingival graft (FGG) to increase the width of Keratinized gingiva (KGW) in dogs. Materials and Methods: This split mouth animal study was performed on 10 mixed breed dogs. The upper second premolar sites were randomly selected for grafting by XADM (test) or FGG (control). Measurements of KGW were recorded before surgery, 1, 3, and 6 months after surgery. Biopsies from grafted sites for histologic and histomorphometric evaluations were harvested 6 months after surgery. Data were analyzed by repeated measured, paired samples t-test, and Wilcoxon Signed rank test. P < 0.05 was considered statistically significant. Results: KGW increased in the two study groups after surgery with no significant statistical difference between them at any time intervals (P > 0.05). The graft shrinkage was 23% and 21% for the test and control groups, respectively, without statistically significant difference (P > 0.05). Histomorphometric evaluation showed no significant difference between the two study groups. Foreign body reaction was not seen in any of the study groups. Conclusion: Increased KWG was similar between the two study groups. With regard to FGG limitations, XADM may be assumed as a suitable alternative for FGG. It should be noted that this research was an animal study and clinical trials on human should be performed to approve the efficacy and safety of this material.

Background: Pulpotomy is the most common pulp treatment of primary molars, where surgical amputation of infected coronal pulp results in preserving the vitality and function of radicular pulp. With introduction of newer materials, the emphasis has shifted towards regeneration, in this scenario; novel materials such as platelet derived growth factor (PDGF) and propolis (PS) have been considered. Materials and Methods: This was a single-blind in vivo study; ninety human primary teeth from children aged between 5 and 10 years were divided into three equal groups in whom pulpotomy procedure was performed and they were recalled after 3- and 6-month interval for histological evaluation. Observations were subjected to statistical analysis using Pearson's Chi-square test. Results: No statistically significant difference was found between the three materials with respect to inflammatory response, soft-tissue organization, and dentin bridge formation (P > 0.05). Majority of the samples in both growth factor and propolis exhibited dentin bridges at the interface of the exposed pulp, bringing or attempting to bridge the site exposed to the pulpotomy material. The ability of the material to evoke a foreign and inflammatory cell response in the pulpal tissue was not significant. The samples of both formocresol and growth factor group showed signs of pulpal necrosis which revealed the presence of a mild necrotic zone in one specimen at 3 months. One specimen from the propolis group showed mild areas of necrosis at the end of 6 months, where none of the specimens in the growth factor group showed areas of necrosis at the end of 6 months. Conclusion: The results of the present study showed a positive outcome for growth factor and propolis groups. Further clinical trials with a larger sample size and long-term review have to be conducted for the material to be used widely.

Background: There are controversies on the analgesic and anti-inflammatory effects of low-level laser therapy on pain, edema, and trismus after mandibular third molar extraction surgery. This study aimed to evaluate the efficacy of low-level laser therapy (LLLT) on discomforts occurring after the mandibular wisdom tooth removal. Materials and Methods: This double-blind, split-mouth design, randomized clinical trial study was performed on 36 healthy controls with bilateral symmetrical mandibular third molar referred to the Department of Oral and Maxillofacial Surgery of Dental Faculty from January to November 2019. After surgical extraction, the laser group underwent laser (Ga-Al-As diode laser, 808 nm, 200 mW) intraorally and extraorally just after surgery and 24 h after surgery. For the placebo group, the handpiece was inserted without laser irradiation. The pain level was assessed by Baker Wong scale at 2, 4, 6, 12, 24, 36, 48, and 60 h postoperatively, and the edema and the extent of mouth opening were examined before surgery, at the 1^st and 7^th days after surgery. The data were collected and analyzed by SPSS at the significant level of 0.05. Results: The statistical analysis of 32 participants' data (laser group: n = 32, placebo group: n = 32) indicated that the mean score of pain in 3 days after surgery in the interventional group was significantly lower than the score of the placebo group (P < 0.001). Furthermore, the swelling and the extent of the mouth opening differed significantly between the two groups at 1^st and 7^th days after the procedure (P < 0.001). Conclusion: Our findings showed that the LLLT had beneficial effects on the management of pain, edema, and trismus following after 3^rd molar extraction surgery.

Background: The fetal amniotic membrane is a biological graft with unique qualities which all lead to wound protection, reducing discomfort, and achieving adequate epithelialization. Materials and Methods: In this animal study, the second and third premolars of the mandible of 4 dogs were extracted. After 4 weeks, 20 mm of mandibular premolar site area were resected on both sides. The created defects on both sides were filled with xenograft. On one side, an amniotic membrane was placed over the graft particles and the reflected flap was sutured. The amount of bone formation in the defects was measured after 4 weeks for two of the dogs and after 8 weeks for the other two, using a caliper. Three histopathological samples from both sides were taken. The collected data were subjected to statistical analysis (Wilcoxon signed-rank and paired sample t-test) using SPSS software at a significant P = 0.05. Results: In the test group, the quantity of bone was 56.81, whereas in the control group bone quantity was 37.38 with statistically significant differences (P = 0.025). In the amniotic membrane group, the inflammation intensity after the graft procedure was moderate (50%) in comparison to the control group where the inflammation was severe (62.5%) (P = 0.041). Conclusion: The amniotic membrane can induce positive osteoinduction effects and be helpful in repairmen of bone defects such as the natural periosteum.

Background: Odontogenic keratocyst (OKC) is one of the most common jaw cysts with high recurrence rate. Some possible factors affecting recurrence that have not been evaluated in previous studies are examined in this study. This study aimed to predict the recurrence rate of OKC and more viable treatment of OKC. Materials and Methods: In this descriptive, analytical, and cross-sectional study, 10 recurrent OKCs, which both slides before and after recurrence were accessible, were collected from oral and maxillofacial pathology department's archive. First, they were evaluated based on common histopathologic features. In the second phase, the frequency of these findings in 36 OKCs (24 samples with recurrence and 12 without recurrence after 5 years) was evaluated based on clinical, radiological, and histopathologic features. Data were analyzed by SPSS, Wilcoxon signed-rank test, McNamara, t-test, Chi-square, Mann–Whitney, Fisher's exact test, Cohen's kappa coefficient, and odds ratio (P < 0/05). Results: According to this study, OKC in women, with multilocular radiolucency and mitosis in basal layer of epithelium as well as diffused inflammation, were statistically associated with probability of recurrence (P = 0.05, 0.035, 0.033, and 0.045, respectively). The corrugated surface, reverse polarity, hypercellularity in parabasal, and satellite cysts can affect the recurrence of OKC with odds ratios = 2.364, 2.364, 1.190, and 1.500, respectively). Conclusion: Gender (women), multilocular radiolucency, diffused inflammation in stroma, and mitosis in basal layer of epithelial lining, can statically predict the possibility of recurrence rate. In addition, findings regarding the age (in younger patients), corrugated surface, reverse polarity, and sub-basal cleft can be helpful in predicting recurrence.

Background: Dental anxiety has negative effects on dentists' pain management. Patients have different levels of pain tolerance. Therefore, providing psychological interventions can reduce treatment avoidance and promote oral health. This study compared the effect of acceptance and commitment therapy (ACT) and cognitive behavioral therapy (CBT) on pain coping strategies and pain perception intensity in patients with dental anxiety. Materials and Methods: This clinical trial with a pretest–posttest control group design and a 3-month follow-up period was performed on 45 patients with dental anxiety. They were randomly selected by convenience sampling method and assigned to two experimental groups and one control group. The first experimental group underwent 10 sessions of ACT, the second experimental group underwent 10 sessions of CBT, and the control group underwent oral care training. Data were collected by the Rosenstiel and Keefe's Coping Strategies Questionnaire and McGill Pain Questionnaire and analyzed by SPSS (version 24) software. The considered significance level is 0.05. Results: The results showed no significant difference between ACT and CBT in pain coping strategies and pain perception intensity (P < 0.05) but indicated a significant difference between the treatment groups and the control group. Moreover, the results showed a significant difference between posttest and follow-up and pretest in pain coping strategies and pain perception intensity (P < 0.01) but indicated no significant difference between posttest and follow-up (P < 0.05). Conclusion: ACT and CBT can play an important role in the sustainable improvement of pain coping strategies and pain perception intensity in patients with dental anxiety.

Ameloblastoma is a benign tumor of odontogenic epithelium which is slow growing, locally invasive, expansive that may result with asymmetries of the face. Conservative treatment of odontogenic tumors with marsupialization is not common but can be done successfully in those with cystic pattern. The aim of this case and literature review is to propose marsupialization as an initial procedure for its treatment. We have presented a case of an ameloblastoma involving 56-year-old male patient. Orthopantomography and computed tomography showed the lesion extended between the right molar region and left molar region of mandible with both buccal and lingual expansion and root resorptions. On clinical examination, expansions of mandible and slight tooth mobilities were seen. An incisional biopsy was carried out and histopathologic examination revealed ameloblastoma although clinical features of lesion were more suggestive of cyst. Our case was treated by obturator marsupialization with a good healing. This case and review of the literature discusses the available treatment option according to macroscopic features of jaw lesions and emphasizes on the importance of the most conservative treatment option. Conservative treatment preserves integrity of bones while radical treatment can leave major cosmetic and functional sequelae such as pathologic fractures, complication with reconstruction plates.

Background: General anesthesia in dentistry has been widely utilized in cases of uncontrollable fear/anxiety and uncooperative patients, patients of young age, and those allergic to local anesthesia and with other existing systemic diseases. These people usually require re-treatment owing to their weak immunity. Our study investigates the frequency and the prevalence of re-treatment in patients and candidates for dental procedure under general anesthesia in Isfahan during 1393–1396. Materials and Methods: The present cross-sectional study randomly chose 162 patients who were candidates for dental procedures. Patients who came in for re-treatment twice or more during this period were identified and their records were requested from the archives. Demographic data, reason for using general anesthesia, underlying disease, physical condition, and mental condition were all gathered through a questionnaire. The causative etiology of re-treatment was identified by examining the patients' medical records including restorations, denervation, tooth extraction, filling, and pulpotomy. Statistical analysis was performed using the SPSS software (version 25) and tests such as Kolmogorov–Smirnov Z-test, Spearman, and Chi-square test. P < 0.05 was considered statistically significant. Results: The findings of the present study showed that 92.25% of patients needed dental re-treatment during their second visit. The most needed treatment was in the second repair session and the least was related to prosthetics. It was also noted that 42.15% of patients needed dental treatment at the third visit and the highest need for treatment was in the third prosthesis session and the lowest reason was related to tooth restoration and extraction. Conclusion: The most needed treatment was in the second session of endodontic treatment, and in the third session, tooth extraction was one of the required treatments, which indicates the progression of dental problems in the interval between treatments.

Background: This study presented a cleaning method for orthodontic NiTi-closed coils and evaluated its effect on the force characteristics of these coils. Materials and Methods: In this in vitro study, 160 orthodontic NiTi-closed coils, 160 orthodontic NiTi-closed coils (9 mm) from two brands G and H and DB, randomly assigned into four groups. Group 1: Three times of immersion in the 10% hydrochloric acid (HCI) solution for 1 min followed by the immersion in 5.25% sodium hypochlorite solution for 5 min. Group 2: Three times autoclave sterilization. Group 3: Three times of immersion in 10% HCI solution for 1 min, followed by the immersion in 5.25% sodium hypochlorite solution for 5 min and autoclave sterilization. Group 4: No immersion and no sterilization. The forces of coils were measured at 25, 23, 21, 19, and 17 mm extension. To measure the force characteristics of coils, an electromechanical universal testing machine was used. For the statistical analysis, Kolmogorov–Smirnov, Kruskal–Wallis, and Mann–Whitney U-tests were used at 0.05 significance level. Results: In G and H coils, no significant differences between the mean forces of different groups were found in any extensions. In DB coils, only in 25 mm extension, there were no significant differences between the groups (P = 0.144). In 17-, 19-, and 21-mm extensions, significant differences (P < 0.001) were found like in 23 mm extension (P = 0.05). In both brands, more extension makes significant more forces statistically (P < 0.01). In all extensions, G and H coils have significant less forces (P < 0.001). Conclusion: Immersion in HCl, 10% for 1 min followed by the immersion in NaOCl, 5.25% for 5 min followed by autoclave sterilization, even three times repeating of this process, did not result in significant changes in the force characteristics of A-NiTi-closed coils.

Background: Infants and children who experience pain in early life, show long-term changes in terms of pain perception and related behaviors. Local anesthesia is integral to the practice of painless dentistry but the pain of injection itself is deterrent to successful administration of local anesthesia and can be a most anxiety-provoking procedure. Distraction as a behavior management technique is successfully known to reduce pain and manage children's dental behavior by diverting their attention away from painful stimuli during invasive dental procedure. This study aimed to compare the pain associated with local anesthetic injection delivered with and without the use of distraction as a behavior management technique in 6–8-year-old children. Materials and Methods: In this randomized, clinical, in vivo study with a split-mouth design we compared the pain of 30 children (6–8-year-old), requiring dental treatment necessitating the use of local anesthesia bilaterally in either of their maxillary and mandibular arches. Treatment was done in two visits, 1 week apart. Children were randomly assigned to receive the distraction (iPad) at one visit while no distraction in other visits. Two different pain assessment scales were used: Wong-Baker faces pain scale (FPS) and FPS-Revised. The Chi-square test was used for statistical analysis. P ≤ 0.05 was considered to be statistical significance. Results: Children who received local anesthesia with audiovisual distraction had lower pain rating scores than those who received local anesthesia with no distraction. Conclusion: Audiovisual distraction significantly reduces pain associated with injection of local anesthesia.

Background: Zinc oxide (ZnO) and graphene oxide (GO) nanoparticles (NPs) have antimicrobial properties. The present study was undertaken to evaluate the effects of incorporating these NPs and their chemical and physical blends on abrasion, translucency, and microhardness of flowable composite resin. Materials and Methods: In the present in vitro study, flowable composite resin samples (Grandio Flow, VOCO, Germany) were evaluated in 5 groups and the sample size was 10 for each group of each experiment (n = 10) as follows: Group 1, without NPs; Group 2, with ZnO NPs; Group 3, with GO NPs; Group 4, containing a physical mixture of GO and ZnO; and Group 5, containing a chemical mixture of GO and ZnO NPs. In all the groups, 1 wt% of the NPs were incorporate into flowable composite resin. Abrasion, translucency, and microhardness of the samples were evaluated. Data were analyzed with analysis of variance, followed by post hoc Tukey's tests at the level of significance of P < 0.05. Results: In Groups 2, 4, and 5 (all the groups containing ZnO), a significant decrease in abrasion and microhardness of flowable composite resin was observed compared to the control group. Incorporation of NPs in all the groups resulted in a significant decrease in translucency compared to the control group. Conclusion: Incorporation of NPs into flowable composite resin resulted in a decrease in translucency. The microhardness was reduced in groups containing ZnO, but the abrasion was also reduced in these groups. The incorporation of GO did not significantly alter the abrasion and microhardness of the composite resin.

Background: This study aimed to assess the microshear bond strength (micro-SBS) of two universal adhesives with different pH values in etch-and-rinse (E and R) and self-etch (SE) modes to superficial dentin. Materials and Methods: This in vitro experimental study evaluated 75 extracted sound human third molars. Superficial dentin was exposed by trimming the enamel and removing 0.5–1 mm of tooth structure beyond the dentinoenamel junction. A 600-grit abrasive paper was used to create smear layer. The teeth were randomly divided into five groups (n = 15). All-Bond Universal and G-Premio Bond were applied in E and R and SE modes in four groups. Clearfil SE Bond was used in the control group. Z350XT composite cylinders (0.9 mm diameter and 1.5 mm height) were then bonded to the prepared surface. The teeth were incubated at 37°C and 100% humidity for 24 h. Micro-SBS was measured by a universal testing machine, and the mode of failure was determined under a stereomicroscope. Data were analyzed using ANOVA, Bonferroni test, and Fisher's exact test (alpha = 0.05). Results: The micro-SBS of Clearfil SE Bond was significantly lower than all other groups (P < 0.05). All-Bond Universal yielded the maximum micro-SBS in SE and minimum micro-SBS in E and R mode. All-Bond Universal showed significantly lower micro-SBS in E and R mode than SE mode (P < 0.05). No other significant differences were noted. The mode of failure was also significantly different among the groups (P < 0.05). Mixed failure had the highest frequency in G-Premio in E and R mode. Conclusion: Type of adhesive and application mode affected the micro-shear bond strength to superficial dentin.

Background: Periodontitis, the second most common reason for tooth loss in adults, is a chronic inflammatory condition that increases the prevalence of cancer by inhibiting apoptosis and promoting tumor cell growth. However, it is still debatable if tooth loss is an important risk factor in oral cancer (OC). The aim of this systematic review is to analyze the relationship between tooth loss and the probability of developing head-and-neck cancer and also to see if there is an association between tooth loss, periodontitis, and the risk of OC. Materials and Methods: Studies that depicted a link between tooth loss and OC (till 2017) were searched from online databases accompanied by a thorough manual search of relevant journals. Data were collected from eligible studies, and meta-analysis was carried out using the Meta-Analysis software. The effect of various inclusions was assessed by sensitivity and subgroup analysis. Publication bias was also evaluated. Results: The meta-analysis consisted of 15 publications. When the number of teeth lost was counted, there was significant variability (I2 = 98.7%, P = 0.0001). When more than 15 teeth were missing in a subgroup analysis, there was a 2.4 times greater risk of OC (odds ratio: 2.496, 95% confidence interval [CI] = 2.067–3.015, P = 0.001) with no heterogeneity (I2 = 0.00%, 95% CI for I2 = 0.00–68.98). Subgroup analysis revealed that there was no evidence of publication bias. Conclusion: It was concluded that tooth loss can increase the OC risk by nearly 2 folds. However, large-scale population-based studies are needed to substantiate the findings.

Background: The aim of the current study was to evaluate the outcomes and complications of three-unit porcelain-fused-to-metal tooth-implant-supported prostheses in comparison with implant-supported prostheses. Materials and Methods: In this review article, the electronic databases, PubMed, Scopus, LILACS, Web of Science, EBSCO, LIVIVO, and Embase were searched over the past 20 years until December 2021. Risk ratio with 95% confidence interval (CI), fixed effect model, and Mantel–Haenszel method was calculated. The meta-analysis was performed with the statistical software Stata/MP v. 16. Results: Two hundred and three studies were selected for reviewing the abstracts, from which the full texts of 16 studies were reviewed. Finally, five studies were selected. The risk ratio of prosthesis failure between the tooth-implant-supported prosthesis and the implant-supported prosthesis was RR (Risk Ratio)= 1.83 (0.79, 4.24), (P = 0.16) and for prosthesis complication, it was RR = 0.61 (0.35, 1.06), (P = 0.08). Risk ratio of implant failure between the mentioned groups was RR = 2.33 (0.84, 6.41), (P = 0.10), and for implant complications, this rate was 0.09 (RR, 0.09 95% CI − 1.30, 1.48; P = 0.90). Conclusion: The meta-analysis of the present study showed that there was no significant difference between the two groups (three-unit porcelain-fused-to-metal tooth-implant-supported prosthesis and implant-supported prosthesis reconstruction) in terms of the total failure of implants and prostheses and the complication rate of implants and prostheses.

Background: The aim of the study was to compare the root reinforcement potential of different light cured intraorifice barriers (TheraCal, lime-lite, Ionoseal and resin-modified glass-ionomer [RMGI] [Fuji II LC]) with or without bonding agent placed in the orifice of endodontically treated and bleached teeth. Materials and Methods: In this experimental in vitro study, single-rooted bovine teeth were instrumented and obturated with gutta-percha. Except the control group, in other specimens, gutta-percha was removed 3 mm under cementoenamel junction. Then, the specimens were divided into seven groups according to the bases was applied: TheraCal LC, TheraCal LC with bonding agent, Lime-Lite, Lime-Lite with bonding agent, Ionoseal, Ionoseal with bonding agent, and RMGI (Fuji II LC). After internal bleaching, the teeth were decoronated. Then, all the groups were subjected to fracture resistance testing using Universal Testing Machine. For evaluating fracture resistance, analysis of variance and Tukey's test were used and for comparing the mode of fracture fisher test was applied in SPSS software. The significance was determined at (α = 0.05) confidence interval. Results: The group of TheraCal LC with bonding agent showed better fracture resistance as compared to the control group (P = 0.004). Although there was no statistically significant difference in the pairwise comparison between the other groups. Conclusion: TheraCal LC with bonding agent can be used as intraorifice barriers with good fracture resistance in endodontically treated and bleached teeth.

Background: The use of photodynamic therapy (PDT) has been evaluated as an adjunctive technique for bacterial decontamination of implants with peri-implantitis. Given the controversies over the efficacy of the application of PDT to treat peri-implant diseases, the present clinical study aimed to evaluate the posttherapeutic clinical parameters and cytokine levels in peri-implant crevicular fluid in patients with peri-implant mucosal inflammation, receiving mechanical debridement (MD) alone or in association with PDT. Materials and Methods: In this double-blinded randomized clinical trial, 52 patients with peri-implant mucosal inflammation were selected and they were randomly assigned to 2 treatment groups: a MD group and an MD + PDT group using an 805 nm laser and indocyanine green (ICG). Although the decrease in bleeding on probing was the primary outcome, pocket depth, PUS, pain on probing, clinical attachment level, gingival recession, tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and matrix metalloproteinase-8 were also evaluated at baseline, 2-week, and 3-month postintervention. Repeated measure analysis of variance was used to analyze inter-group differences and a P ≤ 0.05 was considered for significant differences between tested parameters. Results: Statistically significant improvements (P < 0.001) were detected for all variables after comparison of baseline data with those collected at each time interval of the study. Nevertheless, the inter-group comparisons of these variables between the baseline, 2-week, and 3-month intervals did not reveal any significant decrease in sites treated with either MD alone or MD + PDT. Conclusion: The application of PDT using 805-nm laser and ICG as an adjunct therapy to MD did not provide any additional improvements in the clinical or biologic parameters of peri-implant mucosal inflammation.

Background: Decontaminating the implant surface, exposed to bacterial biofilm, is a concern in the treatment of peri-implant inflammatory disease. The aim of this study was to compare the effect of several methods on reduction of the bacterial load, colonized on the surfaces of titanium discs. Materials and Methods: In this in vivo study, seven titanium discs with Sandblasted, Large-grit, acid-etched (SLA) surface were placed in the mouth of each of ten patients with chronic periodontitis by an intra-oral maxillary splint for 24 h. In each patient, the contaminated discs, except for the negative control ones, were randomly treated by one of the six antiseptic methods including sterile normal saline, plastic curette, air polisher, hydrogen peroxide, 980 nm diode laser, and Er-YAG laser. A spectrophotometer was used to measure Optical Density (OD) in case of aerobic microorganisms. Colony-Forming Units (CFUs) were used for anaerobic bacteria. Data were analyzed through Kruskal–Wallis and Mann–Whitney Tests at a significance level of α =0.05 by SPSS software. Results: Statistical analysis showed a significant decrease in OD of aerobic bacteria among the seven groups during a 0–24 h time interval (P < 0.001). Furthermore, these tests showed a significant difference in the CFU (P < 0.001) for anaerobic bacteria after 48 h. Conclusion: The results of this study showed that all of the adopted methods significantly reduced microbial colonies on the surfaces of titanium discs with SLA surface. Er: YAG laser and normal saline had the highest and the lowest effects, respectively.

Background: There is some concern that root resection may alter the surface features and crack formation of the previously set orthograde material. The aim of this in vitro study was to evaluate the crack formation in orthograde mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) plugs after root resection. Materials and Methods: This in vitro study was conducted on 170 extracted human maxillary anterior teeth. The teeth were randomly divided three experimental (n = 50) and control (n = 20) groups. In Group 1, after root canal treatment, half of the roots were cut with a bur, and the other half with an ultrasonic cutter. In Groups 2 and 3, after the 4-mm CEM and MTA plugs were placed and set, the root ends of half of the samples were cut with a bur and the other half by an ultrasonic cutter. The prevalence of cracks in the dentin and orthograde apical plugs of MTA and CEM was then assessed by scanning electron microscopy. Data were analyzed using the McNemar's, Chi-square, and Fisher's exact tests at P ≤ 0.05 level of significance. Results: In general, the prevalence of crack in dentin in Groups 2 and 3 was significantly higher than in the plug (P < 0.05). There was no significant difference in the prevalence of dentin crack in the studied groups (P > 0.05). The prevalence of crack in dentin was lower when the bur was used to cut off the end of the root, although the difference was not significant. The prevalence of crack in the plug was similar in CEM and MTA. Conclusion: Based on the results of this study, the prevalence of crack in dentin is always significantly higher than its prevalence in the plug, and the prevalence of crack in the plug was similar in CEM and MTA; then, when there is an orthograde access to the root canal and surgery is likely in future, MTA and CEM can be placed in an orthograde technique and it just resects the root during surgery.

Background: Comparing the net setting time and radiopacity of an Iranian glass ionomer cement (GIC) and Fuji II (GC, Japan) according to ISO 9917-1:2007 standard. Materials and Methods: In this experimental/in vitro study, for both tests, we prepared 20 samples of Fuji II glass ionomer (self-cure restorative glass ionomer, batch number: 1608031, GC Corporation, Tokyo, Japan) and Iranian glass ionomer (Ava Tajhiz Dandan-Iran) at P/L of 2/7:1. Then, to determine the net setting time, we prepared a metal mold with dimensions of 10 mm in length, 8 mm in width, and 5 mm in height. Ninety seconds after mixing, the surface of the sample was subjected to the indenter, and the net setting time was recorded as the time elapsed between the end of the mixing and the time needle stopped making a complete circular indentation. To determine radiopacity, the specimens were poured into a mold with a diameter of 15 mm and thickness of 1 mm. Samples and a step wedge were irradiated with X-rays. Particle size analysis and Energy-dispersive X-ray spectroscopy (EDS) analysis were also done for both cements. Test results were investigated with SPSS and through independent t-test (P < 0.05). Results: The mean value of net setting time for Fuji II was 4.83 min and for the Iranian Glass ionomer was 3.83 min (P < 0.05). The mean value of radiopacity for Fuji II was 2.3 mmAL and for Iranian Glass ionomer was 1.9 mmAl (P < 0.05). Conclusion: Net setting time and radiopacity of the glass ionomers were within the range of ISO 9917-1:2007. If all properties of the Iranian cement are set appropriately in future investigations, we propose to use it instead of Fuji II GIC. This has the additional benefit of being cost-efficient as Iranian cement costs less than Fuji II cement.

It is a major concern to select a proper ceramic with acceptable strength and esthetic and minimum antagonist wear. Therefore, different ceramics were introduced to obtain these advantages with various surface treatments. The aim of this study is to evaluate and report the wear behavior of polished and glazed feldspathic and zirconia crowns in published articles up to 2020. Five electronic databases which were used in this research were MEDLINE (via PubMed), Web of Science, Cochrane Library, Embase, and Scopus from the starting date of databases to January 2020. The Keywords “zirconia,” “feldspathic,” “dental ceramic,” “enamel,” “Y-TZP,” “wear,” “glazed,” and “polished” were used. English articles were selected in this paper. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was used as a reporting template as much as possible. Among the initially 133 articles, 59 duplicated articles were removed, and finally, 52 articles were screened and among them, only 16 articles remained for full-text regaining. The results showed that zirconia had significantly less antagonist wear than feldspathic groups, and polishing had less enamel wear than other types of surface treatment like glazing. Only one study showed that glazed zirconia can have more antagonist wear than feldspathic porcelain. Monolithic zirconia had less enamel wear than conventional zirconia and low-fusing feldspathic porcelain showed lower antagonist wear in comparing with other types of feldspathic porcelains.

Background: The aim of this research was to assess the effectiveness of eggshell–membrane (ESM)-containing hyaluronic acid (HA) in the treatment of open gingival embrasure (OGE) following orthodontic tooth movement (OTM). Materials and Methods: This study is an in vivo quasi experimental research. A total of 24 Cavia cobaya were equally divided into two groups, treatment (10% HA injection) and control (phosphate-buffered saline [PBS]). A separator was inserted between mandibular incisors to induce an OGE. A volume of 20 μl of either PBS (n = 12) or ESM extract (n = 12) was locally injected within the interdental papilla. Decapitation of animals was made on day 1, 4, and 7 postinjection. The staining was done using hemotoxylin and eosin to observe angiogenesis and Mallory to observe the collagen density. Fourier-transform infrared spectroscopy (FTIR) and thin-layer chromatography (TLC) analysis were performed to detect the amount of HA available in ESM. The results were then compared with independent t-tests and the Mann–Whitney test. The level of statistical significance was set at 0.05. Results: The FTIR and TLC analysis showed that HA was successfully identified in the ESM samples. Local injection of 10% HA induced an increase of angiogenesis compared to the control group on day 1 and 4 postinjection (P < 0.05). Significant differences (P < 0.05) were also noted in the collagen density and the growth of interdental papilla on day 4 and 7 postinjection. Conclusion: ESM has the potential effect of regenerating the interdental papilla construction after OTM by increasing the collagen fiber density and inducing angiogenesis.

Background: To compare and evaluate the oral hygiene status among institutionalized visually impaired children using the Verbal, Braille, and Audio-Tactile method. Materials and Methods: The present study was a single-blinded, randomized clinical trial with a total of 96 visually impaired children both male and female, aged 6–16 years old were included in this study from a residential school for blind. They were divided into three groups: Group 1 − Verbal method, Group 2 − Braille method, and Group 3 − Audio-Tactile method. Baseline oral hygiene scores were recorded using the debris index, calculus index, gingival index and hand scaling was performed for all the children. Fone's brushing technique was taught to all the groups and fluoridated toothpaste was given to the children with 3 and 6 months of follow-up. Periodic reinforcement of oral hygiene instructions was done for each group. The collected data were tabulated and analyzed using the ANOVA test with (P < 0.01). Results: There was significant improvement in debris index, gingival index, and calculus index in all the three groups by the end of 6 months. All the three indices showed improvement in oral hygiene. Conclusion: Visually impaired children could maintain a respectable level of oral hygiene when taught specialized methods. However, periodic reinforcement is mandatory for good oral hygiene maintenance. Hence, it is recommended to use the combination of Verbal, Braille, and Audio-Tactile method for the best treatment outcomes in these special children.

Background: Professionalism is a multidimensional concept, defined as conducting oneself with responsibility, integrity, accountability, and excellence. This study aimed to contextualize American Dental Education Association (ADEA) tool on action on professionalism in dental education in Mashhad and apply it in a cross-sectional study. Materials and Methods: This descriptive-analytic study was conducted on all students of Mashhad School during 2018–2019. The ADEA tool for action on professionalism in dental education was applied. It was firstly contextualized, validated, and its reliability was confirmed by test–retest and Cronbach's alpha. Then, it was applied in a cross-sectional study. Data were analyzed using Lisrel, and SPSS: 16. ANOVA and Tukey's honestly significant difference tests were used to compare the study variables. Results: The tool was valid and reliable for applying in the Iranian context (x2/df <3, RMSEA ≈ 0.1 and indices of comparative fit index, incremental fit index, goodness-of-fit index, and adjusted GFI are >0.7). In the cross-sectional study for measuring professionalism, the mean score of 1^st-year dental students was significantly higher than 3^rd-year dental students (F = 2.75, P = 0.002). Furthermore, the mean score of 1^st-year dental students was also significantly higher than 6^th-year students (F = 4.53, P = 0.001). The comparison of the component of professionalism among 1^st-to 6^th-year students showed that there was no statistically significant difference between the total score of males and females. In addition, no statistically significant difference was found between the total score of local and nonlocal students. Conclusion: The Tool is valid and reliable for applying in the Iranian context. Dental students need to be trained and also practice professional behaviors during their senior years of college.

Background: Considering the important role of fluoride in preventing caries by reducing the number and activity of cariogenic bacteria and introducing new fluoride-releasing tooth-colored restorative materials, this study was performed to compare and evaluate fluoride ion release and antibacterial activity of resin-modified GI, zirconomer, giomer (Beautifil), and Cention N. Materials and Methods: In this experimental in vitro study, eighty samples (20 samples in each group) were prepared, 10 samples for fluoride testing and 10 samples for antibacterial activity. To evaluate the release of fluoride (PPM), fluoride ion-selective electrode was used on days 1^st, 3^rd, 7^th, 14^th, and 21^st; and antibacterial activities against Streptococcus mutans were examined using direct contact test by absorption of light hourly once every 5 h and days 1^st, 2^nd, and 7^th using an ELISA reader with a microplate reader of 800 TS at a wavelength of 630 nm. The results were analyzed using one-way ANOVA, Tamhane post hoc test, and paired t-test in SPSS software (IBM, Somers, NJ, USA) at a significant level of (P < 0.05). Results: The release of fluoride from materials showed a statistically significant difference (P < 0.001). The maximum mean of fluoride released during the 1^st, 3^rd and 7^th days belonged to the zirconomer group and the minimum for the giomer group. During the measurement period of light absorption from 0 to 24 h after planting, light absorption of foursubstances together was found to be statistically significant (P <.001). Zirconomer light absorption increased on the 7^th day, unlike other substances, but still, the minimum light absorption was related to zirconomer. Conclusion: The highest fluoride release was in zirconomer, Cention N, fuji II LC, and giomer, sequentially. Zirconomer showed maximum and giomer showed minimum antibacterial activities.

Background: One of the most important objectives of pediatric dentistry during dental practice is pain control and effective anesthesia. Because of the limitations of inferior alveolar nerve block (IANB), other techniques such as infiltration injection are suggested. Infiltration technique by using some other solutions such as articaine is an appropriate alteration for mandibular anesthesia. The aim of this study is to compare the efficacy of IANB using lidocaine with infiltration injection by articaine in mandibular second primary molar anesthesia in 8–11-year-old children. Materials and Methods: This is a randomized, cross-over, clinical trial that was performed on 42 children aged 8–11 years, who needed extraction of both mandibular second primary molars. After clinical and radiographic investigations, block or infiltration injection was chosen randomly and treatment was performed in one side in each session. Patient's behavior was registered in two steps of injection and extraction by SEM scores. For comparison of the two sides, Wilcoxon–signed rank test was used (P < 0.05). Results: We concluded that infiltration technique resulted in decrease of all the three SEM scores in comparison to block injection (P < 0.05). The effectiveness of two techniques during tooth extraction, although grade of lidocaine block was more than infiltrate, was not statistically significant. Conclusion: It seems that infiltration technique with articaine is a better substitute for block technique in the extraction of mandibular primary molars.

Background: Preservation of pulpal vitality is of paramount importance as the vital functioning pulp is capable of initiating a unique reparative capacity. The present study aimed to evaluate and compare four regenerative materials for pulpotomy in primary molars. Materials and Methods: This in vivo study included a total of 120 primary molars from 30 healthy children aged 3–9 years for regenerative pulpotomy procedure. The teeth were then divided by the lottery method (chits with names of materials on it) into four groups so that each child received all four of the regenerative materials; Group 1: Biodentine (BD)™, Group II: Mineral Trioxide Aggregate Plus (MTA Plus™), Group III: Retro MTA (Retro MTA^®), and Group IV: Calcium Enriched Mixture (CEM) cement. All the primary molars (1^st/2^nd molars) were evaluated clinically and radiographically at 6, 12, 18, and 24 months. Data were subjected to the statistical analysis using the Chi-square test. The level of significance was considered as P < 0.05. Results: Clinical evaluation showed 100% success with BD™ and CEM cement; whereas 96.2% success was seen with MTA Plus™ and Retro MTA^®. On radiographic evaluation, MTA Plus™ and CEM cement showed 96.2% success, whereas BD™ and Retro MTA^® showed 92.59% success rate. Conclusion: All four regenerative materials showed high success in the pulpotomy of primary molars.

Background: Despite significant improvements in the physical and esthetic properties of modern composite resins, there are still concerns about their biocompatibility. The aim of the current study was to evaluate the toxicity of X-tra fil, Grandio, and Admira Fusion composites on dental pulp stem cells (DPSCs) and human gingival fibroblast (HGF) cells. Materials and Methods: In this in vitro experimental study, 48 composite disks were made using Grandio, Admira Fusion (2 mm high and 4 mm in diameter), and X-tra fil (4 mm high and 4 mm in diameter) composites and cured for 40 s. The composite blocks were then crushed with a sterile mortar and dissolved in phosphate saline buffer solution. Tetrazolium salt (3-(4,5-dimethyl thiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT_, neutral red (NR) assay, flow cytometry, and quantitative real-time polymerase chain reaction (RT-PCR) tests (n = 5) were used to evaluate the toxicity of the composites on two cell types (HGF, DPSCs). Data were analyzed using one-way ANOVA test followed by Newman–Keuls test. Level of significance was set at P < 0.05. Results: According to the results of MTT test, only Grandio showed a significant cytotoxicity in DPSCs, but in HGF cells, Grandio and X-tra fil both showed a significant cytotoxicity. In NR test, Grandio and X-tra fil composites showed a significant cytotoxicity on both HGF and DPSC cells. RT-PCR test results on both DPSC and HGF cells indicated that bax gene expression in the Grandio composite was significant. In this test, the nonexpression of the bcl2 gene in DPSCs was significant in Grandio (100 and 200 μg/ml) and in X-tra fil (200 μg/ml). All of the tests performed in this study showed no significant toxicity of Admira fusion. Conclusion: Admira Fusion is suitable for oral cells in terms of biocompatibility and can be used as a suitable restorative material for deep restorations near the pulp or adjacent to the gums.

Background: Denture bases undergo repeated flexing during mastication leading to fatigue failure, demanding a high fatigue strength property. Flexural (transverse) strength is required high to prevent catastrophic failure under load for success. Denture base resins are fabricated by three different types of manufacturing: Compression molding, injection molding and computer-aided design (CAD/CAM) milling technique. The study was conducted to identify the denture with the highest flexural strength (Fs) from these methods. Materials and Methods: In this in vitro study. Three groups of 15 PMMA acrylic denture base resins (total 45) were processed into rectangular plates of size 65mm × 10mm × 3mm. The three groups differed in the method of processing as compression molded, injection molded, and prepolymerized CAD/CAM milled resins. A 3-point bend test was used to measure the Fs. One-way analysis of variance (ANOVA) with the Post hoc Tukey method was used for statistical analysis. Data was statistically significant with Post hoc Tukey method significance at P < 0.05. Results: The mean Fs of CAD/CAM, injection molding, and compression molding manufacturing techniques are 97.46, 84.42, and 71.72 respectively and standard deviation obtained are 9.93, 10.42, and 11.58, respectively. Statistical analysis suggested the CAD/CAM technique as the best method for the fabrication of dentures because it had the maximum mean Fs and the lowest Fs standard deviation when compared with compression molding and injection molding. Conclusion: Denture bases fabricated through CAD/CAM technique are more sustainable than the compression-molded and injection-molded denture bases.

Background: Head-and-neck radiotherapy can change oral Candida species and cause candidiasis resistance to common antifungals by making the changes to the oral cavity environment. Voriconazole is a synthetic azole with extensive antifungal activity. The current study aimed at comparing the antifungal activity of fluconazole and voriconazole on Candida species isolated from the oral cavity of patients undergoing head-and-neck radiotherapy. Materials and Methods: The present in vitro study was performed on samples isolated from patients undergoing head-and-neck radiotherapy, before and during radiotherapy. After the identification of the species, the antifungal effect of fluconazole and voriconazole was determined by the microdilution method, and the minimum inhibitory concentration (MIC), the minimum fungicidal concentration, and the antifungal susceptibility of the isolated strains were also measured. The data were analyzed by the Chi-squared and then two-sided Fisher's exact tests. P < 0.05 was considered statistically significant. Results: The study findings showed no significant difference in the susceptibility of Candida albicans to voriconazole and fluconazole before and during radiotherapy. Before radiotherapy, both voriconazole and fluconazole had similar effects on Candida tropicalis, but after radiotherapy, voriconazole was less effective. However, both before and during radiotherapy, fluconazole had a greater antifungal effect than voriconazole on Candida glabrata strains. The MICs of voriconazole and fluconazole for both Candida parapsilosis and Candida krusei isolates were within the susceptible or dose-dependent range. Conclusion: The current study results showed that voriconazole was not more effective than fluconazole in the treatment of oral candidiasis in patients undergoing head-and-neck radiotherapy.

Background: Oral lichen planus (OLP) is a chronic immune-mediated mucocutaneous disorder, with an unknown etiology. Since, both pain and discomfort are observed in patients with the erosive type, many drugs have been studied to alleviate pain and clinical symptoms. The present study aimed to assess the effectiveness of systemic Echinacea on clinical indices of OLP. Materials and Methods: In this randomized, double-blind, placebo-controlled trial, 70 patients with erosive OLP were randomly divided into two groups, and each was treated with Echinacea tablets or placebo, 3 times a day, for 35 days. In addition, betamethasone lotion (0.1%) or nystatin (100,000 units) mouthwash were used by patients. The pain severity (visual analog scale [VAS]), lesion size, and the number of lesions were assessed at baseline and on days 10, 25, and 35 after study initiation. Finally, the obtained data were analyzed by statistical software, and Mann–Whitney test, Wilcoxon test, KaplanMeier, Chi-squared, and paired t-test. Results: The VAS scores in the Echinacea group were significantly reduced at each visit compared to the placebo group (P < 0.001). We observed a significant difference between the two groups (P < 0.01). Conclusion: We showed that Echinacea is an effective and complementary therapy for OLP. Furthermore, in short-term usage, Echinacea is almost completely tolerable.

Background: Silver and zinc oxide (ZnO) nanoparticles have recently become common to coat ligatures in order to take advantage of positive properties of nanoparticles, although there are concerns about their cytotoxicity. This study tended to compare subcutaneous inflammatory response induced by elastomeric orthodontic ligatures coated with silver and ZnO nanoparticles with a control group in rats. Materials and Methods: In this in vitro and animal cross-sectional descriptive-analytical study, silver nanoparticles were synthesized by chemical reduction of silver nitrate solution in the presence of sodium borohydride and ZnO nanoparticles by the same method and by chemical reduction of zinc sulfate solution with sodium hydroxide and were coated on elastomeric ligatures. Subcutaneous inflammation degrees were assessed after 15 and 30 days and were compared in the groups by Kruskal–Wallis test and ordinal generalized estimation equation with exchangeable correlation matrix. All tests were performed with a significance level (P = 0.05). Results: There was a significant difference in terms of degrees of inflammation in the groups coated with ZnO nanoparticles (P = 0.003) and silver nanoparticles (P = 0.04) compared to the control group in 15- and 30-day samples. Zinc nanoparticles caused 3.22 times more inflammation than silver nanoparticles (P = 0.053). The decrease in inflammation was significant over time in all groups (P = 0.001). Conclusion: There was a significant more inflammation in the groups receiving ZnO and silver nanoparticles compared to the control group in 15- and 30-day samples. Silver nanoparticles are probably safer than zinc nanoparticles for tissue and a better material to choose for antibacterial effects.

Background: Dentin hypersensitivity is a prevalent problem, manifested as a short sharp pain. Researchers have used different lasers to treat this condition. The present study aimed to evaluate the effect of 980 and 810-nm high-level diode lasers on dentin hypersensitivity to determine proper laser parameters for clinical applications. Materials and Methods: In this double-blinded randomized clinical trial, seven patients with 60 teeth affected by dentin hypersensitivity were selected for the present double-blind, randomized clinical trial. The patients' teeth were randomly matched and assigned to three groups: Group 1: 980-nm diode laser; Group 2: 810-nm diode laser; and Group 3: Control, which received only the guiding beam. The laser parameters were 1-W power, continuous wave mode, a distance of 1 mm, no contact, a 45° irradiation angle, and a 30-s exposure time using to-and-fro movements. The treatment consisted of two sessions with a 1-week interval. Pain severity was determined with the visual analog scale (VAS) at all the study intervals using a dry ice spray. The data were analyzed with SPSS version 20 using one-way ANOVA, repeated measures ANOVA, and least significant difference tests. Significance level was set at α = 0.05. Results: The changes in VAS were significant only in the first stage (P = 0.046). The mean VAS scores decreased over time in the 810-nm and 980 laser groups. A comparison of VAS changes relative to the baseline revealed significant changes in VAS scores at all the time intervals with both lasers. The two 810 and 980-nm laser groups did not exhibit any significant differences for 2 months postoperatively (P = 0.098). Conclusion: The application of 810 and 980-nm diode lasers at 1-W power and an exposure time of 30 s was effective in decreasing pain in patients with dentin hypersensitivity, with no significant difference between these two lasers.

Background: A significant improvement in the nasal symmetry after presurgical nasoalveolar molding (PNAM) is seen in complete unilateral cleft lip and palate (UCLP) infants. However, the follow-up changes in the nasal symmetry before and after PNAM and surgical repair have not been well documented. Materials and Methods: The purpose of this retrospective study is to assess the progressive changes in the nasal symmetry after PNAM and primary cheiloplasty to 1 year in complete UCLP infants. Out of 28 complete UCLP patients who were given PNAM treatment during the period between January 2014 to March 2019, 19 UCLP infants could be included for the study. Submental oblique photographs at the initial visit (T1), immediately after cheiloplasty (T2), and 1 year (T3) after cheiloplasty were selected, and quantity of nasal asymmetry at each period (T1–T2; T1–T3; and T2–T3) was analyzed by paired t-test (P < 0.05). Results: The quantity of asymmetry revealed that there was a highly significant improvement (P < 0.001) in nasal asymmetry at T1–T2 and T1–T3. Nonsignificant relapse was observed at T2–T3; however, a significant relapse in nasal dome height was observed during this period. Conclusion: The improvement in the nasal symmetry after cheiloplasty in PNAM-treated patients is maintained till 1 year postsurgically though there is a nonsignificant relapse.

The aim of this article is to compare the functional efficiency of tooth-supported overdentures and implant-supported overdentures in patients requiring oral rehabilitation. The comparative quantification of the improvement in functional efficiency is very difficult to assess because of the variations in the study designs like the age of the population studied, the male-to-female ratio, the outcome measures used, the clinical setting in which the implant therapy was provided, oral status of the subjects included and the type of implant therapy provided. In this systematic review, the articles included compared the functional efficiency by assessing the bite force, chewing efficiency, electromyographic (EMG) changes measured by EMG analysis, and patient satisfaction for subjects who have been rehabilitated with either a tooth-supported overdenture or an implant-supported overdenture. This will help the clinicians to better plan the treatment, keeping in mind the long-term prognosis for that particular patient.

It may not be possible to treat large maxillofacial defects by surgical reconstruction alone. Prosthetic rehabilitation is invariably required to restore esthetics and function. Achieving adequate retention, stability, and support in these maxillofacial prostheses is a challenging task. This clinical report describes prosthetic rehabilitation of a midfacial defect following surgical resection of squamous cell carcinoma. The intraoral defect was restored with a maxillary obturator prosthesis with salivary reservoir, and the extraoral defect was restored with magnet-retained facial prosthesis having an acrylic resin framework and an overlying silicone facial prosthesis.

One of the most challenging esthetic concerns in dentistry is conservative replacement of the missing anterior teeth. Although implants are considered to be a better treatment option for rehabilitation of such patients, resin-bonded bridges (RBBs) can conservatively restore the missing teeth and have thus gained popularity over the years. It consists of an artificial tooth with a wing-like extension that is cemented to the adjacent teeth. There are various types of RBBs among which Maryland bridge is the simplest and the popular most due to its micromechanical retention enabled by acid etching of both tooth and metal retainer. It can be fabricated by various techniques and materials. In this case reports, we have discussed about two unique designs of Maryland bridge fabricated by two different materials (Porcelain-fused metal and Graphene) and utilizing two different techniques (conventional and digital).

Background: The chemical bond between the metal and the porcelain component is likely to fail in metal-porcelain restorations. This is due to the thick oxide layer that Cr–Co alloys create. This study aimed to investigate the effect of metal conditioner on controlling the oxide layer formed on the surface of the Sintron alloy and the strength of the metal–porcelain bond. Materials and Methods: In this in vitro study, 33 samples were divided into three groups based on surface treatment (n = 11). In all three groups, an oxide layer was created. In the first group, Shofu metal conditioner, in the second group, metal conditioner of Creation, and in the third group, no metal conditioner was applied. All samples were then subjected to 3000 heat cycles between 5° and 55°C with a stop time of 5 s. The specimens were then placed in a universal testing machine for shear bond testing. A force was applied between the alloy and the porcelain by a 5 kN load cell at the speed of 1 mm/min until a fraction occurred. Intergroup comparison was made by the one-way analysis of variance followed by the Tukey's multiple comparisons test (α = 0.05). Results: The mean shear bond strength of the first group was 34.93 MPa and the mean shear bond strength of the second group was 31.37 MPa. The mean shear bond strength of the first and the second group was significantly higher than the third group (23.37 MPa) (PV < 0.001). Conclusion: The use of metal conditioners between ceramill Sintron alloy and porcelain (Vita VMK MASTER) led to increasing the bond strength.

Background: Although glass-ionomer cement (GIC) has many unique properties and advantages, it still lacks favorable mechanical properties. Cention N is a recent alkasite material with excellent mechanical properties. The purpose of this study was to compare the mechanical properties (fracture toughness [FT] and flexural strength [FS]) and acid buffer capability of an alkasite material to GIC. Materials and Methods: In this in vitro study, a total of 60 samples were prepared using Cention N or GIC. Twenty specimens (n = 10) were prepared using beam-shaped Teflon molds for FS, and twenty specimens (n = 10) were prepared with a similar mold with a notch for FT. These were evaluated on a universal testing machine using a three-point bend test. Twenty (n = 10) disk-shaped specimens were prepared for acid buffer capability. The samples were stored in distilled water for a week. This was followed by immersion in lactic acid with a pH of 4 for calculation of the materials acid buffering capacity at 30 and 60 min from exposure using a pH meter. The data obtained were tabulated and subjected to Kolmogorov–Smirnov test and Shapiro–Wilk test to assess the normal distribution and further analyzed using the Student's t-test to assess the level of significance, P < 0.05 was considered statistically significant. Results: The mean FT, FS, and acid buffer capability of Cention N were significantly higher than GIC at P < 0.05. Conclusion: The present study surmised that Cention N exhibited higher FT, FS, and acid buffer capability than GIC.

Background: The aim of the study was to assess the opportunities and threats of e-learning in dental schools and explore the experiences of dental faculty members in the coronavirus disease-19 (COVID-19) epidemic conditions. Materials and Methods: The present study was a sequential exploratory mixed method study (quantitative-qualitative). In the quantitative phase, a survey study was conducted to investigate the perspectives of faculty members regarding the opportunities and threats of e-learning during the COVID-19 epidemic. The data were analyzed by descriptive indicators (frequency, percentage, mean, and standard deviation) and analytical tests (t-test and analysis of variance). In the qualitative phase, data were collected through semi-structured interviews. In the qualitative phase, the inductive content analysis approach of Graneheim and Lundman was used to analyze the interviews. Results: In this study, 213 faculty members of dental schools of Iran participated; among whom 100 were men (46.9%) and 133 were women (53.1%). The results indicated the mean scores of the perspectives of faculty members regarding the opportunities and threats of e-learning in dentistry (4.05 ± 0.49 out of 5). Experiences of the participants in the qualitative phase were explored in the theme of “ups and downs of e-learning in dentistry” with three categories “unaccountability of e-learning in dental education,” “challenges of human resource empowerment in the e-learning process,” and “planned education.” Conclusion: The majority of the faculty members agreed with the use of e-learning in dental education and considered it as an opportunity. However, educational design for blended learning, creation of appropriate infrastructures, and empowerment of human resources as e-teacher and e-student were emphasized as key requirements for e-learning development in dental schools.

Background: To overcome the drawbacks of sinus floor augmentation procedures newer surgical techniques to reduce sinus perforation such as crestal approach sinus kit (CAS) and piezosurgery, which are minimally invasive procedures enabling uncomplicated sinus elevation have evolved. The aim of the present study was to investigate the performance of CAS kit compared to piezosurgery during maxillary sinus membrane elevation. Materials and Methods: A total of 40 subjects requiring maxillary sinus membrane augmentation for rehabilitation with implant prosthesis in posterior maxilla were included in the study. The current study was a prospective clinical trial where osteotomy and sinus elevation was done using CAS kit in Group 1 and piezosurgery in Group 2. Platelet-rich fibrin was placed in osteotomy site and dental implants were inserted. Implant stability was evaluated at baseline and 3 months. Crestal bone loss was measured at 3, 6, and 12 months. Apical bone gain was measured at 6 and 12 months. Intragroup comparison of the study groups was done by Paired t-test, ANOVA test, and Friedman test. Intergroup comparison was done by unpaired t-test and Mann–Whitney U-test. P < 0.05 was considered statistically significant. Results: Implant stability improved in both the groups, i.e., 79.2 ± 5.02 and 79 ± 5.31 in Group 1 and Group 2, respectively, at 3 months. Intergroup comparison showed no difference in all parameters; however, crestal bone loss was greater in piezosurgery group with a mean difference of 0.74 mm. Conclusion: Both CAS and piezosurgery groups showed definitive improvement in all parameters. CAS group resulted in added benefits in terms of less crestal bone loss and intraoperative surgical time compared to piezosurgery group.

Background: The aim of the study was to compare the root coverage percentage and other clinical outcomes in Millers Class I and Class II gingival recessions (GR) treated with modified coronally advanced flap (MCAF) combined with connective tissue graft (CTG) using macro and microsurgical approaches. Materials and Methods: In this controlled clinical trial, a total of 32 Miller's Class I and Class II GR defects were randomly assigned to the control and test groups (16 in each group). All the patients were treated with MCAF with CTG as the root coverage procedure. For the control and test groups, the procedure was performed using a macro and microsurgical approach, respectively. Clinical parameters were assessed at baseline and in 6^th month. Wilcoxon signed–rank test was used to compare the values between baseline and 6 months. Statistical significance was set at P < 0.05. 1 week after surgery, wound healing index (WHI) and Visual Analog Scale (VAS) scores were recorded. Results: Intragroup comparisons revealed significant improvement in all the parameters in both the groups at 6 months. The proportion of root coverage achieved in the control and test groups was 78% and 86%, respectively. At 6 months, the root coverage percentage between the study groups showed no significant difference (P = 0.207). Intergroup analysis of WHI and VAS scores showed better healing and less postoperative pain in the microsurgical group compared to macrosurgical group (P < 0.05). Conclusion: At 6 months, there were no significant differences in root coverage percentage or other clinical parameters between the groups based on whether a macro or microsurgical method was used. However, better wound healing, less pain, and discomfort were observed in the microsurgical group.

Background: The delayed diagnosis of oral squamous cell carcinoma (OSCC) affects therapeutic and prognostic strategies, and provides regional recurrence or distant metastasis. The tumor-infiltrating lymphocytes (TILs) are known as a critical diagnostic biomarker in antitumor immune response. We evaluated the association between CD4⁺ T-lymphocyte marker, some clinicopathological indices, and the impact of TILs on the stage and grade of OSCC. Materials and Methods: In this cross-sectional study, 37 OSCC specimens including 16 early and 21 advanced stages (categorized base-on recent clinical oncology references) and their related healthy surgical margin (as internal control group) were collected. Obtained histochemical data were analyzed by SPSS V.23 software. The expression of CD4⁺ marker in tumor microenvironment (TME) was compared by nonparametric Mann–Whitney and Kruskal–Wallis as well as Fisher's exact tests. P < 0.05 was remarked statistically significant. Results: The low-grade patients represented more CD4⁺ TIL that was statistically significant (P = 0.011). However, there was no statistically significant difference in CD4⁺ TIL between various stages (P = 0.404), tumor size, and lymph node involvement (P > 0.05). Moreover, there was no significant relation between TIL infiltration, age, and tumor localization (P > 0.05), however CD4⁺ expression in women was more than men (P = 0.008). The CD4⁺ T-lymphocyte infiltration in TME was more significant than healthy surgical margin (P < 0.001). There was a statistically significant difference between healthy surgical margin and different grades and stages of OSCCs that lower grades demonstrated more CD4⁺ TIL infiltration (P < 0.001). Conclusion: The CD4⁺ T-lymphocytes may play important role in differentiation and maturity of epithelial cell, tumorigenesis, and progression of OSCC.

Background: Chronic periodontitis (CP) is characterized by an immune response, leading to the destruction of periodontal supporting tissue. The effect of inflammatory and genetic factors on periodontitis has been evaluated previously. The interleukin (IL-17) as an inflammation regulator seems to play a critical role in periodontitis pathogenesis. Here, in the current study, we aimed to investigate the association of -197 G > A (rs2275913) IL-17 gene promoter polymorphism with generalized severe CP in an Iranian population. Materials and Methods: In this case–control study, a total of 54 patients with periodontitis and 118 normals were enrolled. The polymerase chain reaction-restriction fragment length polymorphism technique was applied to detect IL-17 promoter rs2275913 genotypes in association with the susceptibility to severe CP. Chi-square test or Fisher's exact test was employed to compare genotype frequencies between groups. P < 0.05 were considered statistically significant. Results: The distribution of genotypes and alleles was in Hardy–Weinberg equilibrium. Although no significant association was observed between the risk of periodontitis and genotype frequencies under any of the inheritance models, the GG genotype was higher in healthy controls, while the AG genotype was more frequently observed in patients under the codominant model ([odd ratio [OR] = 2.14, 95% confidence interval (CI) (1.01–4.53), P = 0.13]). The frequency of AG-AA genotype was higher in patients under dominant inheritance model ([OR = 1.92, 95% CI (0.94–3.93), P = 0.068]), while GG-AA and AG genotypes were higher in healthy controls under over dominant model (OR = 0.1.95, 95% CI [0.98-3.86], P = 0.055). Conclusion: The results of this study showed that the presence of allele A and AG genotypes could be considered possible factors in increasing the risk of developing CP, although the differences of allele and genotype frequencies were remarkable but not statistically significant between the two groups.

Background: Pulpotomy is one of the common vital pulp therapy procedures for primary molars. The present trend in pulpotomy materials is to use regenerative materials that promote dentinogenesis. Mineral trioxide aggregate (MTA) is a very popular pulpotomy material. However, it has some limitations including difficult handling characteristics and long setting time. Tricalcium silicate cements evolved, in which bioceramic cements came into existence, have better properties than MTA. The aims and objectives of the study are to evaluate the efficacy of bioceramic putty with MTA as a pulp medicament in primary molars. Materials and Methods: In this randomized in vivo study, sixty primary molars in children aged 4–9 years indicated for pulpotomy were selected. They were assigned using nonprobability convenient sampling technique into two groups: test group – bioceramic putty (EndoSequence Root Repair Material) and control group – MTA (Angelus). After pulp therapy, teeth were restored with stainless steel crowns. Recall clinical and radiographic evaluation was done at 3-, 6-, and 12-month interval to assess success rate. The data were statistically analyzed using Chi-square test, and P ≤ 0.05 was set for statistical significance. Results: At 3-month interval, the success rates were 96.7% and 93.1% with bioceramic and MTA groups, respectively. At 6- and 12-month interval, the success rates were 93.3% and 93.1% with bioceramic and MTA groups, respectively. However, the difference in success rate between the groups was statistically not significant at all the time intervals (P = 0.533 at 3 months, P = 0.972 at 6 and 12 months). Conclusion: Bioceramic putty exhibited comparable results to MTA. Hence, it can be considered alternative pulpotomy agent.

The restoration of speech, deglutition, mastication, and respiration in patients with bimaxillary resection involving the maxillae, hard and soft palates, and paranasal sinuses poses a significant challenge. This clinical report describes the prosthodontic management of a patient with bilateral maxillectomy caused due to post-COVID-19 mucormycosis. A patient-specific implants (PSI) that matched the remnants of the zygoma complex was designed to improve the patient's severely impaired speech and swallowing. The patient's postsurgical anatomy was first visualized using three-dimensional computed tomography data. Following that, a customized zygoma-supported titanium framework was designed to support the prosthesis based on the data. Two weeks after the framework was installed, an open-tray impression was made and the prosthesis was fabricated. These findings suggest that PSI-retained prosthesis can be considered in cases with severely compromised maxillary bone anatomy, impaired oral functioning, and no viable conventional reconstruction options.

Background: The main drawbacks of zirconia are its high refractive index and opacity. This study aimed to assess the effect of sintering temperature on the translucency of Ivoclar e. max ZirCAD (IEZ), and White Peaks Symphony (WPS) zirconia blocks. Materials and Methods: In this in vitro experimental study, 30 IEZ and 30 WPS zirconia blocks measuring 10 mm × 10 mm × 1 mm were prepared and underwent sintering in three subgroups at 1440°C, 1500°C, and 1530°C. The specimens were then photographed against a black and a white background with a standard digital camera. The L*, a*, and b* color parameters were measured using Adobe Photoshop software, and translucency was calculated. Data were analyzed using one-way ANOVA and Tukey's test (P < 0.05). Results: In both the IEZ and WPS groups, the maximum and minimum translucency parameters were recorded in 1530°C and 1440°C subgroups, respectively. The difference in the mean translucency was significant among the three subgroups of each zirconia group (P < 0.001). The mean translucency of WPS zirconia was significantly higher than that of IEZ zirconia (P < 0.01), and maximum difference was noted at 1500°C sintering temperature. Conclusion: Increasing the sintering temperature from 1440°C to 1530°C can significantly increase the translucency of IEZ and WPS zirconia blocks, and can be considered to improve the quality of zirconia restorations.

Background: Graphene oxide (GO), a product of graphite, is a candidate for nano-reinforcing cement-based materials due to its good water dispersibility and excellent mechanical properties. On the other hand, zinc oxide (ZnO) is well-known for its antibacterial characteristics as well. Therefore, we aimed to evaluate the impacts of adding ZnO and GO nanoparticles on the antibacterial properties of flowable composites. Materials and Methods: In this, in vitro experimental study was designated into five groups containing: (1) no nanoparticles as control group, (2) 1 wt.% ZnO nanoparticle, (3) 1 wt.% GO, (4) 1 wt.% physical compound of ZnO and GO, and (5) 1 wt.% chemical compound of ZnO and GO. The antibacterial properties of composite resin discs were evaluated by direct contact test. Data were analyzed using a one-way analysis of variance, followed by Tukey's post hoc tests (P = 0.05). Results: Streptococcus mutans colony counting in the first 24 h showed the least growth rate in the chemical compound group (2.2 × 10^[5]). However, in 7 days, the least colony number was observed in the GO group (2 × 10^[3]). Moreover, the physical compound showed the least bacterial adhesion. Conclusion: Adding GO alone to composites, compared to adding ZnO or physical and chemical compounds of GO-ZnO, was more helpful to increase the antimicrobial characteristics.

Background: A new method to improve the properties of the materials is nano-encapsulation, which improves the biological properties, antibacterial activity along with reduction of toxicity. Due to the spread of nano-knowledge, the present study was performed to evaluate the antibacterial effect of nano-chlorhexidine (CHX) on Enterococcus faecalis biofilm in the root canal system. Materials and Methods: In this in vitro experimental study, 55 matured single-root mandibular premolars were decoronated and the canals were prepared by single length method up to #F3 ProTaper Universal system. Five teeth were selected as negative control. Then, the teeth were randomly divided into three experimental groups (n = 15) and a positive control group (n = 5). The experimental groups were irrigated with 2% nano- CHX gel, 2% CHX solution, and 5.25% sodium hypochlorite (NaOCl), respectively. Finally, the number of colonies was counted. Kruskal–Wallis test was used to compare the number of colonies among groups. The level of significance was set at P < 0.05. Results: The mean number of colonies in the groups of nano-CHX, NaOCl, CHX, and positive control were obtained as 17.73 ± 18.69, 35.53 ± 36.42, 38.8 ± 31.8, and 96.8 ± 22.52, respectively. There was a significant decrease in the number of colonies in all the experimental groups compared to the control group (P < 0.05). However, difference in the number of colonies among these three groups was not significant (P > 0.05). Conclusion: The use of nano-CHX in removing E. faecalis biofilm from root canal is as effective as the use of CHX and NaOCl.

Background: This study aims to compare cytotoxicity and induced apoptosis of a new bioceramic cement containing different concentrations of simvastatin on stem cells from human exfoliated deciduous teeth (SHED). Materials and Methods: This research was an in vitro study. To evaluate the cytotoxicity and induced apoptosis of the bioceramic cement containing different concentrations of simvastatin, the SHED were exposed to the cement during 1, 3, and 7 days. Pure bioceramic cement and pure simvastatin with concentrations of 1, 0.1, and 0.01 μM were also tested to evaluate the possible synergic effect. Mineral trioxide aggregate (MTA) as the gold standard of pulp dressing materials was compared. MTT assay and Annexin V assay were used to evaluate cytotoxicity and induced apoptosis, respectively. The data were analyzed using ANOVA and Tukey post hoc tests at the significance level of 0.05. Results: During 7 days, MTA, bioceramic cement, simvastatin 0.1 and 0.01 μM, and bioceramic cement containing 0.1 and 0.01 μM simvastatin increased (P < 0.05) and simvastatin with concentration of 1 μM decreased the cell viability (P < 0.05). Except for MTA and bioceramic cement containing 0.1 and 0.01 μM simvastatin, all other compounds induced apoptosis within 7 days (P < 0.05). Conclusion: After 7 days, the viability of the SHED in the presence of a new bioceramic cement containing 0.1 and 0.01 μM simvastatin was not compromised. Moreover, this cement showed superior results than MTA and provided an environment for cell proliferation. This finding appears to be due to the pharmacological effects of low concentrations of simvastatin.

Reconstruction of functional occlusion in case of a large surgical defect of the mandible involving partial mandibulectomy remains a significant challenge to the maxillofacial surgeon and prosthodontist. Removable appliances and the conventional implant-supported prosthesis are precluded in this case due to the absence of normal anatomical contours of the bone. In recent years, due to the advancement of technology, bone graft reconstruction with computer-guided rehabilitation of the functional occlusion has been advocated to reverse the debilitating effects of the hemimandibulectomy defect. This clinical report describes the prosthodontic management of fibular graft reconstructed mandible by computer-aided design–computer-aided manufacturing guided implant-supported prosthesis.

From the perspectives of longevity, mechanical performance, and economics, amalgam has long been considered the material of choice, especially for certain types of restorations in posterior teeth, including replacement therapy for existing amalgam fillings. In spite of numerous advantages over other filling materials, its use has been decreasing in recent years and the alternative tooth-colored filling materials are increasingly used. There is a trend towards minimal interventional, adhesive, techniques in dentistry, which are based on adhesion to tooth structure by chemical interaction and/or micromechanical retention. At the same time, the quality and durability of alternative materials have improved. Mercury is the metallic element of concern used in dental amalgam. Mercury is a well-documented toxicant, with reasonably well-defined characteristics for the major forms of exposure, involving elemental mercury as well as organic and inorganic mercury compounds. Looking into the kind of practice and its popularity among dentists and the patients in India, even we have to comply with the use of amalgam by implementing the best possible ways to minimize the extent of damage to nature.

Background: This study aimed to investigate the extent of apical transportation following instrumentation with EdgeEvolve rotary instruments applying single-length and crown-down techniques. Materials and Methods: In this experimental in-vitro study, 60 mandibular molars with mesiobuccal curvatures of 20°–40° were selected, and digital radiographic images were taken. Teeth were randomly assigned into two groups of single-length and crown-down preparation techniques. In both mentioned groups, EdgeEvolve rotary system was used. After preparation, the same as the previous ones, digital radiographic images were taken from the canals. The data were analyzed using Student's t-test and ShapiroWilk normality test (P = 0.05). Results: The mean standard deviation (SD) for apical transportation in the single-length and the crown-down group was 4.42 (2.9) and 7.48 (3.9) degrees, respectively (P < 0.05). The mean SD of the preparation time in the single-length and crown-down group was 135.07 (30.8) and 109.07 (20.8), respectively (P < 0.05). The apical transportation and the time of preparation between the two groups were significant. Conclusion: Using EdgeEvolve rotary instruments canal preparation with both single-length and crown-down techniques led to some degrees of apical transportation.

Many patients, particularly adults, may prefer clear aligner treatment due to its esthetics and ease of use. Some studies have shown that mechanical vibration can affect the rate of tooth movement and other aspects of orthodontic treatment. The purpose of this systematic review was to substantiate the effects of vibration as an adjunct to clear aligner treatment. A comprehensive search of the PubMed, Embase, Cochrane library, and Scopus and also hand searching of reference lists was conducted for finding published studies up to March 2021. Two authors reviewed the titles and abstracts independently to select relevant studies and the full texts where there was some skepticism. Seven papers were included in this study following removing duplicates and irrelevant studies, four of which were randomized controlled trial and three were retrospective studies. In the majority of studies, High-Frequency Vibration (HFV) has shown to be effective in accelerating tooth movement and reducing the exchange interval of aligners. Little data have advocated that HFV can increase bone density, reduce pain or root resorption. It seems that HFV is more effective than low frequency vibration in patients treated with clear aligners. Based on a low level of certainty, HFV can increase the rate of tooth movement and decrease the exchange interval of clear aligners. Further investigation is necessary to clarify the effects of vibration on pain and discomfort, bone density, and root resorption.

Background: Patient cooperation is necessary for treatment success in removable orthodontics. Every factor has an adverse effect on appliances appearance can impede appliance wearing. This study investigated the effect of immersion in household cleaner and bleach liquids on fracture resistance of self-cure orthodontic acrylic resins. Materials and Methods: This in vitro study two orthodontic acrylic resins (Megadental^® and Acropars^®) were used. Eighty identical acrylic samples (50 mm × 5 mm × 3 mm) from each acrylic resin were fabricated and divided into four groups (n = 20). For each type of acrylic resin; Group 1: 15 min immersion in household cleaner liquid (hydrochloric acid [HCl], 10%), 1 min rinsing with running water, 15 min immersion in household bleach liquid (sodium hypochlorite [NaOCl], 5.25%) and 1 min rinsing with running water were done. For Group 2, two times and for Group 3, three times immersion just like Group 1, were done. Group 4, as control, had no immersion. Fracture resistance of samples was measured with universal testing machine (Instron) in 3-point bending set-up. Data were analyzed with two-way repeated measurement ANOVA. Significance level was set at 0.05. Results: Fracture resistance of Acropars groups was greater than counterpart Megadental ones (P < 0.001). Immersion factor, alone (P = 0.375) and in combination with material (P = 0.603), did not make a significant difference among fracture resistance of each acrylic resin groups. Conclusion: 15 min immersion in household cleaner liquid (HCl acid) followed by 15 min immersion in household bleach liquid (NaOCl 5.25%) and even 3 times repetition of this process had not significant adverse effect on fracture resistance of acrylic resins.

Background: Chronic kidney disease (CKD) is a systemic disease with a major burden on several life aspects, including oral health. As life expectancy has improved in CKD patients, oral health status has become important regarding their quality of life. The aim of this study was to investigate oral health and oral health-related quality of life (OHRQoL) in CKD patients. Materials and Methods: This was a cross-sectional study. Patients' age, gender, and estimated glomerular filtration rate (eGFR) stage were recorded. Oral Health Impact Profile-14 (OHIP-14) was used to evaluate OHRQoL. Decayed, missing, and filled teeth (DMFT) index was utilized to record oral health status. SPSS software was used to analyze data. One-way ANOVA, t-test and Pearson/Spearman correlations were used. P < 0.05 was considered statistically significant. Results: One hundred and four patients participated; 60.6% male versus 39.4% female. Mean age was 52.1 ± 18.1 years. The most frequent eGFR stage was 5 (41.2%). Mean DMFT score was 18.7 ± 8.5. Mean OHIP-14 score was 14.82 ± 5.86. DMFT score was significantly correlated with OHIP-14 total score as well as its physical domains (P < 0.05). The correlation between eGFR stage and OHIP-14/DMFT score was both statistically significant (P = 0.03/P = 0.02, respectively). Conclusion: DMFT score was significantly correlated with OHRQoL in CKD patients, especially regarding its physical domains. Paying attention to fulfill dental treatment needs seems mandatory to improve OHRQoL and overall quality of life in these patients.

Pulpectomy aims at retaining the tooth in the asymptomatic state until exfoliation. Root canal obturating materials should resorb in synchronization with the primary root and get eliminated rapidly upon accidental extrusion. This systematic review aims at appraising the clinical and radiographic outcomes of Endoflas as an obturating material for primary teeth. An extensive literature search on obturating materials used for primary teeth using MeSH terms in PubMed, Cochrane library, and Ovid® from September 2002 to March 2020. Studies evaluating the clinical and radiographic success of Endoflas as an obturating material in children were included. From 45 retrieved articles, eight qualified for the systematic review. Moderate quality of evidence was elicited in this review. There was a dramatic reduction of inter radicular radiolucency in Endoflas obturated teeth compared to other root canal filling materials. Even for resorption of the extruded material beyond the apex too, Endoflas has depicted a faster clearance rate. Hence,it was concluded that, Endoflas can be a potential root canal obturating material for treating the primary teeth, even with furcal radiolucency. We recommend randomized clinical trials satisfying all the norms of CONSORT guidelines to provide a high quality of evidence.

Background: Thalassemia major (TM) is a severe life-threatening hemoglobinopathy. It causes a typical chipmunk face due to increased hematopoiesis. Severe malocclusion often accompanies facial deformity, which may affect Oral Health-related Quality of Life (OHRQoL). The aim of this study was to assess the relationship between orthodontic treatment needs and OHRQoL in TM patients. Materials and Methods: One hundred and five adult patients with TM participated in this cross-sectional study. Oral Health Impact Profile-14 (OHIP-14) questionnaire was used to measure OHRQoL and the patient's need for orthodontic treatment was evaluated using the Index of Orthodontic Treatment Need (IOTN). The comparison of OHIP-14 scores between groups regarding orthodontic treatment need was carried out using t-test (SPSS software); P < 0.05 was considered statistically significant. Results: The mean age of participants was 24.92 (±9.33) years, with 52% female versus 48% male. Orthodontic treatment need was 27.6%. The mean score of OHIP-14 was 12.95 (±7.02). A statistically significant relationship was found between OHIP-14 score and age, gender, and orthodontic treatment need (P < 0.05). All domains of OHIP-14 were significantly related to orthodontic treatment need (P < 0.05), except for “physical disability” (P = 0.282). Conclusion: OHRQoL was lower in TM patients with orthodontic treatment needs. Planning to treat malocclusion seems necessary to improve the quality of life in these patients.

Background: Continuing professional development (CPD) is a life-long learning process for all health-care members including dentists to improve their knowledge and skills in their profession and provide the best quality services. This study aimed to assess the needs, priorities, and obstacles of attending dentists in these programs in Isfahan province, in 2020. Materials and Methods: This descriptive-analytical cross-sectional study was performed on general dentists in Isfahan province. Data were collected through a three-part questionnaire, online and on paper; it included demographic information, prioritization of seven disciplines, and scoring of 33 dental subfields, as well as obstacles limiting participation in the CPD programs. This questionnaire was developed and validated by researchers. Statistical analysis was carried out through Mann–Whitney, Kruskal–Wallis, and Chi-square tests, and a significance level of 0.05 was considered. Results: Of 326 dentists (90.5% response rate) participating in this study, 157 were (48.2%) female, and most of them were in the high work experience group (45.1%). The highest mean scores standard deviation related to the dentist's interest and needs, among the seven dental disciplines, belonged to practice management (6.68 [2.9]), oral and dental reconstruction (6.29 [2.55]), and pediatric dentistry (6.291 [2.87]). On the other hand, lack of time (70.6%), inefficient teaching methods and organization (65%), and irrelevant topics (58.6%) were the most common obstacles limiting dentists in the CPD programs. Conclusion: Based on the results of this study, dentists in Isfahan province reported more interest and need to participate in some fields of CPD courses including practice management, pediatric dentistry, and oral and dental reconstruction. Thus, a system for continuing education based on dentists' needs and preferences is highly suggested.

Background: Prolonged orthodontic treatment causes complications such as root resorption, gingivitis, and caries. Platelet-rich plasma (PRP) can accelerate the dental movements of orthodontic treatments. The aim of the present study was to evaluate the effect of local PRP injection on the secretion of dentin sialoprotein (DSP) and dentin matrix acidic phosphoprotein (DMP1) biomarkers in gingival crevicular fluid during orthodontic movements in animal samples. Materials and Methods: In this experimental study, one maxillary quadrant of six beagle dogs was randomly selected as the experimental group, and the other side was considered as the control group. Afterward, maxillary of the first premolars was extracted, and then, a titanium nickel coil spring (150 g) was then used between the second premolar and the canine. PRP that was previously activated with CaCl 2-thrombin was injected intraligaman to the experimental side at days 0, 21, and 42. Moreover, the mixture of the CaCl 2-thrombin with placebo was injected in to the control side. The study period was 63 days. Sampling was performed on days 0, 1, 2, 7, 21, 42, and 63. Then, in all the samples, the DSP and DMP1 level was measured using special kits by ELISA method. Data were analyzed by the analysis of variance and t-test. Results: Upon the application of orthodontic forces, the mean DMP1 and DSP levels in the experimental group at different times were significantly increased compared to the control group (P < 0.001). Conclusion: PRP injection enhanced DMP1 and DSP level with probable rise in the rate of root resorption.

Background: Platelet derivatives are enriched growth factors that ameliorate various cellular processes in regeneration. The present clinical trial aimed to evaluate and compare the effects of sticky bone and concentrated growth factors (CGFs) in the treatment of intrabony osseous defects by cone-beam computed tomography (CBCT). Materials and Methods: The study included 20 patients having 40 intrabony defects. 20 sites each were included in both test group (Sticky bone) and Control group (CGF alone). The clinical parameters including probing pocket depth (PPD) and clinical attachment level (CAL) were assessed at baseline and 6 and 12 months posttherapy. The radiographic parameters including the depth, mesiodistal (MD), and the buccolingual (BL) width of the defect to assess the amount of bone fill were examined at baseline and after 12 months using CBCT. Results: Twelve months posttherapy clinical results indicated a significant reduction of PPD and gain in CAL in both the study groups. Similar observations were recorded with CBCT radiographic parameters where the intrabony defect depth and MD defect width for the test group and control group significantly reduced after 12 months' posttherapy (P < 0.0001). However, no significant reduction in BL defect width was observed in control group (P = 0.577) in contrast to the test group (P = 0.028) after 12 months' posttherapy. Conclusion: Intrabony defects treated with sticky bone showed improved clinical and radiographic parameters indicative of enhanced periodontal regeneration as compared to CGF alone treated sites.

When immediate molar implants first were proposed, submerged initial healing and delayed loading were the norm. It is now recognized that some early loading of a nonocclusal nature can stimulate faster osseointegration, although full occlusal loading is still delayed for 3 or more months. Here, we test the hypothesis that earlier occlusal loading of mandibular premolar and molar immediate implants may be possible. In this retrospective case series study, 18 mandibular molar and nine mandibular premolar teeth were atraumatically extracted and immediate implants placed 1–2 mm apical to buccal and lingual crestal bone. Periimplant gaps received particular allograft covered with acellular dermal matrix barrier. Healing abutments were placed through puncture points in the membranes to help in stabilizing the latter and to permit nonsubmerged site healing. At 6−8 weeks, each implant was evaluated for stability using the Periotest® device and restored if the Periotest® (PTV) value seen was negative. Data were analyzed by t test and MannWhitney U at a significance level of P < 0.05. Retrospective assessment of all 27 implants after 5 years' period of follow up showed all implants to have survived. Overall mean crestal bone loss was determined to be−0.25 ± 0.54 mm. Individual mean bone levels for mesial and distal surfaces were−0.24 ± 0.77 mm and−0.26 ± 0.72 mm, respectively (P = 0.78). A statistically significant difference in bone loss between genders was detected. Overall mean probing depth was 2.09 ± 0.57 mm. Based on the widely used Albrektsson criteria, the overall survival and success rate was 100%. Immediate implants placed into mandibular premolar and molar extraction sockets and allowed nonsubmerged healing may be ready for restoration at earlier times than previously thought possible.

Background: The purpose of this in vitro study is to fabricate a novel metal–ceramic prosthesis with a porous structure, to compensate for the disadvantages associated with the design of existing prostheses, and to measure the internal fit of this prosthesis. Materials and Methods: In this in vitro study, the mandibular first molar was scanned from the dental computer-aided-design to design a 3 mm porous structure frame. The frame was produced using the lamination method and fired in a pressed ceramic. For comparison, pore-free specimens were fabricated by selective laser sintering (SLS) as described above, and porous specimens were fabricated by casting (total n = 30). The internal fit was then measured using a digital microscope (at 100× magnification), and the data were analyzed using one-way ANOVA (α = 0.05). Results: The total mean internal discrepancies for each group were 42.32 ± 22.50 μm for the porous structure SLS group (PS-group), 107.54 ± 38.75 μm for no-porous casting group (group), and 121.36 ± 50.19 μm for the no-porous SLS group (group), with significant differences (P < 0.05) among all groups. Conclusion: The internal discrepancies of porous structure crown fabricated by SLS were smaller than that of no-porous crown fabricated by casting and SLS. Based on these laboratory findings, further studies should be conducted to evaluate the feasibility of the newly designed porous structure and press ceramic prosthesis to determine whether they can be applied in clinical practice.

Background: Understanding the influence of age on growth kinetics and telomere length in dental stem cells is essential for the successful development of cell therapies. Hence, the present study compared the basic cellular and phenotypical characteristics of stem cells from human exfoliated deciduous teeth (SHEDs) and dental pulp stem cells (DPSCs) of permanent teeth and their telomere lengths using quantitative real-time polymerase chain reaction. Materials and Methods: The study is an in vitro original research article. Primary cultures of SHED and DPSCs (n = 6 each) were successfully established in vitro, and the parameters analyzed were the morphology, viability, proliferation rate, population doubling time (PDT), phenotypic markers expression, and the relative telomere lengths. Data were analyzed by analysis of variance and P < 0.05 was considered statistically significant. Results: SHED and DPSCs exhibited a small spindle-shaped fibroblast-like morphology with >90% viability. The proliferation assay showed that the cells had a typical growth pattern. The PDT values of SHED and DPSCs were 29.03 ± 9.71 h and 32.05 ± 9.76 h, respectively. Both cells were positive for surface markers CD29, CD44, and CD90. However, they were negative for CD45 and human leukocyte antigen DR. Although the differences in relative telomere lengths between the individual cell lines of SHED and DPSCs were observed, no significant (P > 0.05) variations were found for the mean T/S ratios of both the cells. Conclusion: SHED and DPSCs displayed similar morphology, proliferation rates, and phenotypic features. The relative telomere lengths were slightly shorter in DPSCs than SHED, but the values were not significantly different. Thus, SHED and DPSCs can be considered as recognized sources for regenerative applications in dentistry.

Background: The present study aimed to determine the effect of mouthwashes on the shear bond strength (SBS) and surface roughness (SR) of soft liners. Materials and Methods: In this in vitro study, a total of 72 samples were prepared to evaluate the SBS (n = 36 for each liner). An autopolymerized (Mollosil Plus) and a heat-polymerized liner (Molloplast B) were injected in between two blocks of heat-processed acrylic resin (Triplex). The samples in each liner group were subdivided into three subgroups. Control group samples were totally stored in distilled water. In test groups, samples were immersed in chlorhexidine (CHX) or mouthwash containing ginger extract for 30 min daily. After 20 days, the SBSs were evaluated using a universal testing machine. To evaluate the SR, 30 disk-shaped samples (15mm*10mm) were prepared for each type of liners and stored in the similar solutions; distilled water, CHX and ginger mouthwash (n=10). SR was measured at 1 day and after 90 days with a profilometer. One-way ANOVA, independent t-test, and paired t-test were used to analyze data. P < 0.05 was considered statistically significant. Results: The SBS in Molloplast B liner was significantly higher than Mollosil regardless of type of solution (P < 0.001). In both liners, the mean SBS was not statistically different between the three groups of solutions. Changes in SR were not statistically significant after 90 days, except for the Mollosil group, immersed in ginger extract solution which was increased (P = 0.04). Conclusion: SBS of either group of liners did not change in both mouthwashes; However, SBS of heat-polymerized liner was higher than autopolymerized in all groups. Ginger extract-containing mouthwash increased SR of autopolymerized liner used in this study; whereas, there were no significant changes in the heat-cured liner. According to this study, CHX can be used for the disinfection of prosthesis lined with either type of liners.

Background: White spot formation is one of the common side effects in orthodontic treatments and multiple enamel conditioning might happen even during on session of fixed orthodontic treatments. The aim of the present study was to evaluate the impact of multiple enamel conditioning with different methods on enamel micro-hardness (MH). Materials and Methods: In this In vitro experimental study, the buccal surfaces of 105 extracted premolars were evaluated in seven groups: One control and six experimental groups. The enamel conditioning was performed in three ways: Etching with phosphoric acid 37%, etching with phosphoric acid 37% followed by primer application and conditioning with self-etch primer. The conditioning process in each way was also performed twice consecutively. The specimens were submitted in pH cycling model with demineralization and re-mineralization solutions for 14 days. Afterward Vickers MH test was applied with 0.981N force on the teeth for 10 s indentation time. Data were analyzed using One-Way ANOVA and Tukey HSD (honestly significant difference) test for multiple comparisons. A value of P < 0.05 was considered statistically significant. Results: MH analysis showed statistically significant differences between the control group and the other conditioned groups (P < 0.05). The groups conditioned with acid-etch and primer, particularly twice, showed the lowest amount of MH in comparison to other groups. Self-etch primer had the least effect on MH of the enamel. Single time etching without using primer, made no considerable difference when compared to multiple etching. Conclusion: Etching process and covering the enamel with primer decrease enamel MH. Using self-etch primer is a more conservative method of enamel conditioning.

Background: Oral candidiasis is one of the most common manifestations of patients with cancer under chemotherapy. Due to many side effects of chemical antifungal products and various advantages of herbal extracts like licorice, this study was performed to compare the antifungal effects of nystatin and licorice on yeasts isolated from oral mucosa of patients with cancer receiving chemotherapy. Materials and Methods: In this in vitro study, a total number of 30 patients with oral candidiasis who received chemotherapy were examined. The samples were prepared by using swabs taken from the lesions, and after 48 h, they were transferred and cultured on Sabouraud dextrose agar. The antifungal effect of licorice was compared with nystatin using agar disk diffusion method. These data were entered in SPSS statistical software and were analyzed with Kruskal–Wallis and Mann–Whitney tests. (α = 5%). Results: Four types of candida were identified among all 30 oral lesions (Candida albicans, Candida glabrata, Candida stellatoidea, and Candida SP). The mean inhibition zone diameter around nystatin showed a significant difference (P < 0.001) between C. albicans (9.486), C. glabrata (8.627), C. stellatoidea (7.00), and C. sp (7.06) but the inhibition zone diameter around licorice was almost zero in all groups. Conclusion: Licorice extracts did not show any antifungal effects whereas nystatin showed the most antifungal effect against C. albicans.

Saprophytic molds such as Mucor, Rhizopus, and Absidia cause mucormycosis, a fungal infection. These saprophytic fungi are common in the environment and have a strong proclivity for invading major blood arteries, causing tissue ischemia, necrosis, and infarction. They have been linked to immunocompromised individuals with a history of diabetic ketoacidosis, corticosteroid medication, HIV infection, malignant lymphomas, and patients currently receiving and recovering from COVID-19 treatment. The foregoing is the case of a 78-year-old COVID-19 recovered male who presented with a primary complaint of upper tooth movement for 1 month and maxillary segmental mobility. The maxillary alveolar process was resected, and histopathological reports revealed mucormycosis, which was treated with antifungal medication and nasolabial flap surgery. For the past 6 months, he has been disease-free. Early detection and treatment may offer a higher chance of successfully minimizing this debilitating condition.

Background: The posterior denture teeth wear faster than the anterior teeth, which can result in occlusal interferences, loss of vertical dimension of occlusion, greater stress accumulation in the anterior region, and higher ridge resorption. This study aimed to compare the wear resistance of three types of artificial acrylic teeth before and after removing the glaze layer. Materials and Methods: This in vitro study compared three types of artificial acrylic teeth, namely, Finex (F), SR Orthotyp DCL (S), and Vita Physiodents (V) in six groups (n = 10). Half of the artificial teeth of each brand underwent 0.5-mm buccal reduction to remove the glaze layer (groups FC, SC, and VC). The teeth were thermocycled and placed in a chewing simulator. The teeth with and without the glaze layer were weighed before and after the wear test. The data were analyzed using ANCOVA (the level of significance was 0.05). Results: The weight reduction (indicative of wear) was 0.03 ± 0.02 and 0.12 ± 0.03 mg in Groups S and SC, 0.03 ± 0.02 and 0.25 ± 0.04 mg in Groups V and VC, and 0.11 ± 0.15 and 0.28 ± 0.1 mg in groups F and FC, respectively. Removing the glaze layer (P < 0.01), type and brand of acrylic tooth (P < 0.01), and the baseline weight of artificial teeth (P < 0.01) had significant effects on wear resistance of artificial teeth. Conclusion: The wear of artificial teeth was greater after removing the glaze layer, and the magnitude of wear was also significantly different among the three brands. The group FC showed maximum wear while the groups S and V showed minimum wear.

Background: Oral squamous cell carcinoma (OSCC) is one of the most common cancers. Epstein–Barr virus (EBV) has been related to throat-esophageal and gastric cancers. The aim of this study was to evaluate the prevalence of EBV in OSCC. Materials and Methods: This descriptive-analytical cross-sectional study was performed on 48 samples recorded in the archives of the Oral Pathology Department of Isfahan Dental School with definitive diagnosis of OSCCs prepared by excisional biopsy. Samples were selected in different age groups, locations, and genders. The grade of the tumor malignancy was determined based on Annreroth's classification. The EBV expression was determined by immunohistochemical (IHC) staining. The data were entered into SPSS software and statistically analyzed by t-test, Chi-square, and Fisher's exact test. Significance level was considered P < 0.05. Results: IHC staining for EBV was positive in 25 samples (52%). There was no significant relationship between EBV expression and mean age, gender, clinical feature, and grade of tumor differentiation (P > 0.05). A significant difference was observed between the EBV expression and location (P = 0.035). Furthermore, a significant difference was observed between the grade of tumor and staining intensity distribution index of EBV (P = 0.005). Conclusion: EBV expression was observed in most of the OSCCs, especially in poorly differentiated tumors. The pathogenesis of OSCCs may be related with EBV. OSCCs in buccal mucosa and floor of the mouth have more frequently of EBV expression. Future studies on the mechanisms of EBV and their role in OSCC are required with larger sample sizes.

Background: This study assessed the effect of sodium hypochlorite on cyclic fatigue resistance of RaCe, HyFlex CM and XP-endo Shaper files. Materials and Methods: In this in vitro, experimental study, 90 RaCe, HyFlex CM and XP-endo Shaper files (n = 30 of each) were divided into two groups (n = 45). Group 1 included 15 files of each rotary system, which were immersed in 37°C sodium hypochlorite (5.25%) for 5 min. Group 2 files were immersed in 37°C saline for 5 min. The files underwent cyclic fatigue testing using simulated root canals in which, the rotary files could freely rotate until fracture. Time of fracture was recorded by a chronometer and the number of cycles until fracture was calculated. Data were analyzed using two-way ANOVA and Bonferroni test (α = 0.05). Results: No significant difference existed in the mean number of cycles or rotation time of files between saline and sodium hypochlorite (P > 0.05). The mean rotation time of RaCe was significantly shorter than that of HyFlex and XP-endo Shaper in both solutions (P < 0.05). The mean number of cycles of RaCe was significantly lower than that of HyFlex and XP-endo Shaper files in both solutions (P < 0.05). The mean number of cycles of HyFlex was significantly lower than that of XP-endo Shaper (P < 0.05). >Conclusion: Immersion of rotary files made of different alloys in 5.25% sodium hypochlorite for 5 min had no effect on their fracture resistance. However, type of file alloy affected its fatigue resistance such that XP-endo Shaper showed the highest and RaCe showed the lowest fatigue resistance.

Background: The background of this study was to improve the longevity of a restoration and optimal adaptation of restorative material to the prepared cavity walls is crucial. The study aimed to evaluate the interfacial adaptation of Activa, Micron, and Predicta bulk bioactive restorative materials to coronal dentin using micro-computed tomography (CT) analysis. Materials and Methods: In this in vitro micro-CT assessment study, Class II mesio- and disto-occlusal cavities were prepared on 60 extracted human mandibular molar teeth. After etching and bonding procedures, all the mesial cavities (n = 60) were restored with Tetric N-Ceram and the disto-occlusal cavities with Activa or Micron or Predicta bioactive (n = 20 each) restoratives. Interfacial gap percentages were evaluated under micro-CT before (baseline) and after thermo-mechanical load cycling (TMC). Acquired data were analyzed statistically using one-way analysis of variance, Paired t-test, and Tukey's multiple post hoc procedures, at P < 0.05 level of significance. Results: The interfacial gap percentages were lowest for Predicta bioactive and highest for the Micron group (P < 0.05). The number of gaps increased significantly after TMC in all the groups (P < 0.05). The adaptation of tested materials was inferior to axial wall and pulpal floor, whereas considerably better adaptation was observed on buccal and lingual walls. Conclusion: Predicta bioactive followed by Activa bioactive has shown superior interfacial adaptation, whereas Micron bioactive demonstrated maximum microgaps compared to nanohybrid composite. Artificial aging with TMC has a negative influence on the internal adaptation of all tested materials.

Background: Oral lichen planus (OLP) is a chronic oral mucosal disease. It can manifest as severe erosive/ulcerative oral lesions, causing pain and discomfort. Oral health-related quality of life (OHRQoL) may be deteriorated due to the patient's symptoms. The aim of this study was to evaluate OHRQoL and its relation to oral pain in erosive/ulcerative OLP patients. Materials and Methods: In this cross-sectional study, patients with erosive/ulcerative OLP filled out Chronic oral mucosal disease questionnaire (COMDQ). Meanwhile, they recorded their oral pain through Visual analog scale (VAS). The Pearson's correlation coefficient was used to analyze the relationship between COMDQ score and VAS (IBM SPSS Statistics). P < 0.05 was considered statistically significant. Results: Sixty patients participated in the present study; 51 (85%) were women and 9 (15%) were men. The mean age of participants was 50 ± 14.5 years. The mean score of COMDQ was 47.44 (±18.21). The mean VAS score was 4.5 (±2.4). COMDQ total and all domain scores were significantly correlated with VAS (P < 0.05), except for the “Patient support” domain (P = 0.63). Conclusion: In patients with erosive/ulcerative OLP, there was a significant correlation between oral pain and COMDQ total score, as well as its physical, social, and emotional domains. It seems that COMDQ can be a complementary tool for assessing treatment outcomes in OLP patients.

Background: The aim of the present study is to compare the antibacterial effect of fluoride mouth rinse and fluoride varnish on the primary biofilm formation of Streptococcus mutans (S. mutans) in two types of orthodontic adhesives. Materials and Methods: This is an in vitro study in which forty composite discs of Transbond XT and Lightbond were divided randomly into 4 groups: Group 1: Control group (not treated with fluoride), Group 2: Rinsed by 0.2% fluoride mouth rinse, Group 3: Rinsed by 0.05% fluoride mouth rinse, and Group 4: Treated by varnish fluoride. Then each group was placed in S. mutans suspension. Bacterial suspension from each treatment was subcultured onto the surface of Mueller–Hinton agar plates, and bacterial growth was assessed. The results were analyzed by analysis of variance test and Scheffé test was run to compute the binary groups (P < 0.05). Results: There was a statistically significant reduction in the viability of S. mutans in treated groups by fluoride but no significant difference between two types of composites. Conclusion: The results of this study demonstrated that S. mutans colonies were sensitive to fluoride and their most effective form was varnish. There was no significant difference in early biofilm formation of S. mutans in two types of orthodontic adhesive resins Transbond XT and Lightbond.

The corona virus malady 2019 (COVID-19) pandemic has rekindled the well established argument regarding the role of dental aerosol in transference of severe acute respiratory syndrome corona virus 2 (SARS-CoV-2). Aerosols and droplets are generated amid innumerable dental procedures. With the commencement of the COVID-19 pandemic droplet, a review of the infection/disease control strategies for aerosols is required. We do not know where this pandemic is directed. We do not have conclusive evidence for an optimal management strategy. Every day brings in varying information, so recognizing the hazard created by aerosols will help diminish the probability of infection transfer at the time of dental procedures. Hence, the author assessed the evidence-based medical and dental literature in relation to “aerosol' that documented the source of transmission of aerosol through various potential routes, addressed the risk potential to patients and the dental team, and assessed the additional measures that might minimize the viral transmission if regularly adopted. In this article, the author evaluated and compiled dental guidelines by various countries and various health-care associations in context to aerosol-generating procedures and has made recommendations for the restriction of dental aerosols and splatter in routine dental practice.

Background: Remineralizing agents such as fluoride and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) are popular treatment choices for incipient enamel lesions. Recently introduced resin infiltration enhances the esthetics of teeth affected by these enamel lesions. Furthermore, few studies reported the utilization of colloidal silica infiltration for the white spot lesions. However, the potency of these materials for treatment in primary teeth necessitates investigation. Thus, this study evaluated and compared the effectiveness of CPP-ACP fluoride (CPP-ACPF), resin infiltration, and colloidal silica infiltration on surface microhardness in artificial white spot lesions in primary incisors using the Vickers microhardness testing machine. Materials and Methods: In this in vitro study, on the labial surface of 45 primary incisors, artificial white spot lesions were created by immersing them in a demineralizing solution. According to the evaluation method, random distribution of specimens into three groups: Group 1: CPP-ACPF, Group 2: resin infiltration, and Group 3: colloidal silica infiltration. Specimens after treatment were stored in artificial saliva, followed by microhardness evaluation using Vickers microhardness. Microhardness readings at baseline, post demineralization, and after treating them with different materials were taken. The level of significance was 0.01. Results: Enamel specimens treated with resin infiltration showed a high microhardness mean value compared to CPP-ACPF and colloidal silica infiltration. Conclusion: Resin infiltration is a promising and effective treatment option for incipient enamel lesions followed by CPP-ACPF compared to colloidal silica infiltration in primary teeth.

Background: To consciously select an appropriate dental cement for each type of intracanal post. Materials and Methods: An electronic search was carried out (1970 to 2020) through Medline, PubMed, Scopus, and Google Scholar. The following keywords were searched in title, abstract, or keywords with different combinations: endodontically treated tooth, root canal therapy, dental posts, post and core, prefabricated posts, custom posts, dental cement, resin cements, cement selection, cement, and adhesive resin cement. Results: Evaluating full texts, 146 articles were selected to review the types of posts and cements, selection criteria of appropriate cement for each type of post, and compare the results obtained by different cements. Conclusion: Dental cements affect the survival rate, durability, and success rate of postbased treatments. Considering special characteristics and application of each type of intracanal post, conscious selection of cement is an important determining factor in long-lasting success. Choosing an appropriate cement has a key role in success and durability of dowel posts-based fixed restorations.

Background: Oral health-related quality of life (OHRQoL) assesses the subjective perception of oral health and its impact on the quality of life. The aim of this study is to measure the OHRQoL and its determinants among adult people living in Kerman, Iran. Materials and Methods: In this cross-sectional study, a total of 5657 adult people (18–64 years) residing in the Kerman district, both in the rural and urban areas, were enrolled in the study between September 2014 and April 2018. The Oral Health Impact Profile (OHIP-14) and the oral health indices, such as the total decayed, missing, filled teeth (DMFT), community periodontal index (CPI), gingival index (GI), and xerostomia, were measured by an experienced dentist. The demographic variables of gender, age, educational status, and marital status were also recorded. The impact of the studied variables on OHRQoL was evaluated with multiple logistic regression. Results: Participants were 2239 (39.58%) men, and average age was 45.39. The mean scores for OHRQoL, DMFT, CPI and GI were respectively: 24.07 (7.76), 10.7 (6.86), 0.76 (0.96), 0.63 (0.8). The frequency of people with xerostomia was 37.4. 301 (53.3%) of people had poor quality of life related to oral health. In multivariable analysis, there was a statistically significant increase in OHRQoL with an increase in the DMFT (P < 0.001), xerostomia (P < 0.001), CPI, (P < 0.001). Men had a significantly higher OHIP score than women (P < 0.001). Conclusion: According to the results of this study, DMFT, xerostomia, and CPI scores are strongly related to OHIP scores. In addition, between CPI and GI scores, the CPI score is the better predictor.

Ewing's sarcoma (ES) is an aggressive, poorly differentiated round cell tumor in bone or soft tissues. This rare neoplasm is found primarily in the long bones of limbs and flat bone of pelvis with a predilection in the second decade in life. Primary ES of the maxillofacial region is exceptional and constitute 1% ± 4% of all cases. This case report is aimed at highlighting a very rare clinical presentation of extraosseous ES of the chin region-a first of its kind.

Background: This systematic review aimed to evaluate the efficacy of casein phosphopeptide-amorphous calcium phosphate (CPP-ACPF) varnish for remineralization of white spot lesions (WSLs) “in vitro” in human teeth. Materials and Methods: Literature search included three databases, namely Medline (via PubMed), The Cochrane Controlled Clinical Trials Register, and Google Scholar from 2010 to January 2021. The studies assessing WSL depth, calcium, phosphate ion release, and microhardness due to artificial demineralization or remineralization were considered for review. Reference articles were retrieved, and a customized risk assessment tool was used. The Cochrane risk of bias assessment tool was used to generate the risk of bias summary graph. Meta-analysis was performed using RevMan 5.4. Heterogeneity was evaluated by Cochrane's test, and random effects model was used to pool estimate of effect and its 95% confidence intervals (CIs) for surface microhardness. Results: Eighteen studies were selected for review based on the eligibility criteria. Four studies showed superior remineralizing effect of CPP-ACPF compared to fluoride varnishes. Four studies involving 120 human permanent teeth samples were included in the meta-analysis. Efficacy of CPP-ACPF varnish was equivalent to other fluoride varnishes in improving surface microhardness after remineralization during 7-day period (mean surface microhardness: 3.94, 95% CI [−9.08–1.21], I^2: 75%, P = 0.13). Major risks of bias associated with the studies included in the review were inadequate sample size, improper sample preparation, and unexplained blinding. Conclusion: CPP-ACPF varnish appears to be equally effective as other fluoride varnishes in remineralizing artificially induced WSLs, but quality of evidence is low.

Child's uncooperative behavior can impede the efficient delivery of dental care. Therefore, in spite of exceeding availability of behavior management techniques there is a need to search for a psychological behavior management technique that effectively reduces fear and anxiety during dental treatment and instill a change in child's attitude toward the treatment and is also acceptable by the parents. The aim of our systematic review is to determine the efficacy of various psychological behavior management techniques in managing a child's behavior in pediatric dentistry by assessing the fear and anxiety levels, ease of use by the clinician, application in various operative procedures, and parental acceptance. A systematic search was conducted by two reviewers in databases PubMed, Google Scholar, Scopus, Web of Science, and Cochrane for the studies published from January 1, 2011, to December 31, 2020. Studies included were clinical studies which evaluated the efficacy of various psychological behavior management techniques by evaluating the fear and anxiety levels and the changes in behavior during dental treatment in children aged between 4 and 14 years. The studies selected were then assessed for quality with the help of predetermined criteria which categorized the studies into high, medium, and low. Through search strategy, 7147 articles were yielded. After screening through titles and abstracts, 60 nonduplicated articles were selected which were further screened for full text. At the end, 15 articles were included in systematic review and 3 articles for meta-analysis. It was concluded that all the psychological behavior management techniques aided in reduction of fear and anxiety. In noninvasive procedures, conventional psychological behavior management techniques can be effective but in invasive procedures other newer psychological behavior management techniques showed better results. The aspect of parental acceptance regarding various techniques was not discussed in any of the included studies.

Background: The aim of this study was to evaluate the rate of apical microleakage following the fracture of five types of nickel–titanium rotary file systems (ProTaper Universal, Mtwo, RaCe, Revo-s, HeroShaper) in the apical one-third of the canal. Materials and Methods: In this laboratory experiment, 49 mandibular premolars were collected and randomly divided into seven groups. Root canal treatment was performed by five different rotary file systems with different cross-sections. All files, except in the control groups, were scratched at the 3-mm end by a handpiece. After separation of the apical end of the file in the root canal, the apical seal was measured, using the fluid infiltration technique. Data were analyzed in SPSS, using one-way ANOVA and Tamhane's T2 tests at P < 0.05. Results: The Hero Shaper and RaCe files showed the highest (3.14 μL/min) and the lowest (2.51 μL/min) rates of microleakage over time, respectively. There were significant differences between the Hero Shaper and RaCe files and between Hero Shaper and ProTaper files in terms of microleakage (Tamhane's T2 tests, P < 0.05) Conclusion: The presence of a separated file and its cross-section type affects the apical microleakage.

Background: Polyether ether ketone (PEEK) was recently introduced to dentistry. However, difficulty in provision of a strong durable bond is its main drawback. Thus, precise surface treatment and use of a suitable luting agent are imperative for bonding of PEEK restorations. This study aimed to assess the effect of type of luting agent on shear bond strength (SBS) of PEEK. Materials and Methods: In this in vitro study, 60 square-shaped PEEK samples were fabricated and sandblasted with 110 μm Al₂O₃ particles. The samples were then divided into four groups based on the type of cement used (n = 15): zinc phosphate cement, Panavia F2, Panavia V5, and resin-modified glass-ionomer (RMGI) cement. After bonding, the samples were thermocycled for 5000 cycles. The SBS was measured by a universal testing machine. The surface of samples was inspected under a video measuring machine to determine the mode of failure. Data were analyzed using the Kruskal–Wallis test via SPSS version 24 (α = 0.05). Results: RMGI did not bond to PEEK. The SBS values were 4.02 ± 2.87 megapascals (MPa) for Panavia V5, 10.84 ± 6.05 MPa for Panavia F2, and 10.50 ± 2.88 MPa for zinc phosphate. The SBS in the Panavia V5 group was significantly lower than that in the Panavia F2 (P = 0.001) and zinc phosphate (P < 0.001) groups. No significant difference existed between the Panavia F2 and zinc phosphate groups in this respect (P > 0.05). Conclusion: Panavia F2 resin cement and zinc phosphate conventional cement provided the highest bond strength to PEEK, while RMGI did not bond to PEEK.

Background: Considering the increasing demand for tooth-colored restorations, this study sought to assess the micro-shear bond strength (μSBS) of composite to deep dentin by using mild and ultra-mild universal adhesives. Materials and Methods: This in vitro, experimental study evaluated 75 sound third molar teeth randomized into five groups (n = 15) of Clearfil self-etch (SE) Bond (control), Tokuyama Universal Bond (TUB), and All-Bond Universal (ABU) in etch and rinse (E and R) and SE modes. The occlusal surfaces of the teeth were trimmed to expose deep dentin at 0.5 mm distance from the pulp chamber. Adhesives were applied on the dentin surface according to the manufacturers' instructions, and Z350XT composite cylinders were bonded to dentin using Tygon tubes (0.9 mm internal diameter, 2 mm height). After incubation at 37°C and 100% humidity for 24 h, the teeth underwent μSBS test in a universal testing machine. The mode of failure was also determined under a stereomicroscope. Analysis of variance, Bonferroni test, and Fisher's exact test were applied for data analysis (alpha = 0.05). Results: TUB in E and R mode (13.78 MPa) and ABU in SE mode (7.85 MPa) yielded the maximum and minimum μSBS values, respectively. No significant difference was noted in μSBS of tested universal adhesives in E and R and SE modes to deep dentin (P > 0.05). TUB yielded significantly higher μSBS than ABU (P < 0.05). No significant difference was noted in mode of failure of the groups (P > 0.05). Conclusion: Type of adhesive affected the μSBS but etching mode of universal adhesives had no significant effect on their μSBS to deep dentin.

Background: Over the past year, patients infected by severe acute respiratory syndrome coronavirus-2 presented with severe gustatory dysfunction, the prevalence of which varies among different populations. Furthermore, there have been sporadic reports of oral ulceration observed in coronavirus disease-19 (COVID-19) patients due to varied reasons. The aim of this study was to investigate and characterize the presence of gustatory disorders, oral ulceration, and other oral changes in patients with laboratory-confirmed COVID-19 infection. Materials and Methods: In this cross-sectional observational study, a total of 402 participants who were detected COVID-19 positive by reverse transcription–polymerase chain reaction were included. Their demographic and clinical data were recorded through hospital records. The participants were interviewed either in person or on the telephone to record any change in taste and/or changes within the oral cavity. t-test for independent means was used to compare mean age, while other characteristics were compared by Chi-square test and Z-score test. P < 0.05 was taken as significant. Results: Out of the total sample of 402 individuals, 262 were male and 140 were female. The prevalence of gustatory dysfunction and oral ulceration was 43.53% and 15.67%, respectively, in the studied sample. Significantly more females had gustatory dysfunction than males and older subjects more commonly than younger. The symptom of loss/change of taste and oral ulceration were more probable to occur together. In addition, the tongue was the most common site for ulceration in our studied sample. Conclusion: Loss of taste is a common symptom of COVID-19 patients, whereas oral ulceration is not so commonly reported. However, the presence of both these symptoms could impair the quality of life of patients and hamper adequate nutritional uptake.

Background: Dental trauma is a common problem in children, which mostly occurs at school. Traumatic dental injuries often cause unpleasant experiences for children, and immediate and appropriate measures are needed. Its prognosis depends on immediate posttraumatic measures, and schoolteachers can play a key role in the treatment of children. The current study aimed to investigate teachers' knowledge about dental injuries in primary school children in the city of Isfahan. Materials and Methods: Following a cross-sectional design, the current study was conducted on 248 elementary school teachers who were selected using the simple two-stage random cluster. Then the teachers' knowledge was measured based on a four-choice questionnaire consisted of two parts. According to this questionnaire, teachers were divided into five categories based on their knowledge score which was consist of strongly high knowledge, high knowledge, average knowledge, low awareness, and strongly low knowledge. Data were analyzed using the Spearman correlation coefficient and independent t-test. Statistical significance was considered when P < 0.05. Results: The total knowledge score of teachers was 45.9%. About 61% of the teachers had a history of exposure to dental injuries. Furthermore, 49.6% of them believed milk was the best environment to keep the avulsed teeth. There was no significant association between teachers' knowledge and education level, history of previous trauma, or participation in a training course, but there was a direct association between teachers' knowledge and their work experience (P < 0.05). Female teachers' knowledge score was significantly higher than their male counterparts (P < 0.001). Conclusion: Participants had a moderate level of knowledge about the management of dental traumas. Hence, it is suggested to develop educational programs to increase teachers' awareness about this issue.

Background: This study aimed to assess the relationship between the osteoporotic condition and periodontitis in postmenopausal women. Materials and Methods: Ninety-four women aged 50–80 years were studied in this cross-sectional study. Bone mineral density (BMD) of lumbar vertebra BMD (LBMD), total hip BMD (HBMD), and neck of femur BMD (NBMD) was assessed using standardized dual-energy X-ray absorptiometry (DXA) (normal: T-score ≥−1, osteopenic: −2.5 ≤ t-score <−1, osteoporotic: T-score <−2.5). Bleeding point index (BI), O'Leary plaque index (PI), and clinical attachment loss (CAL) were recorded. Cementoenamel junction, alveolar-crest distance (CEJ-AC) was measured from cone-beam computed tomography images. Periodontitis severity was represented by CAL and CEJ-AC distance. One-way analysis of variance followed by Post hoc Tukey was performed for examining differences among the groups for different variables. Pearson correlation coefficient® and backward regression analysis were used to investigate the effect of confounding variables on CEJ-AC as the dependent variable. Significance was considered at P < 0.05. Results: Mean CEJ-AC was significantly higher in the osteoporotic and osteopenic groups compared to the normal group (P = 0.001). There was a significant positive correlation between CEJ-AC and NBMD and LBMD (P < 0.001). The associations between LBMD and CEJ-AC existed even after adjusting for confounding factors (P = 0.002). The differences in BI, PI, and CAL were not statistically different between the groups (P > 0.05). Conclusion: Although osteoporosis is not the main cause of periodontitis, it can indirectly affect periodontal status by increasing CEJ-AC. Early diagnosis of osteoporosis followed by early referral to a dentist for the treatment of potential existing periodontal diseases is important to avoid complications among postmenopausal women