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

Background: This study clinically and histologically compared the human pulp response to direct pulp capping (DPC) with mineral trioxide aggregate (MTA), Biodentine, and propolis in 2 months. Materials and Methods: In this clinical trial evaluated 41 premolars candidate for extraction due to orthodontic purposes of patients between 15 and 25 years of age. A group of 5 was separated randomly as the negative control. The remaining teeth were randomly divided into three experimental groups of 12 after mechanical exposure of the pulp by bur in high-speed handpiece under air and water spray. The exposed areas were capped with MTA, Biodentine, or propolis. Glass ionomer was applied as base over the cap. The teeth were restored with composite resin. Patients were recalled in 2 months for clinical and radiographic examinations and also pulp vitality test. Teeth were then extracted. Slides were prepared and tissue sections were evaluated for the presence and severity of inflammation, dentinal bridge, and continuity. Data were analyzed using the Chi-square and Fisher's exact tests. Results: The clinical success rate was 100% in the MTA and 91.7% in both the propolis and Biodentine groups. The presence and severity of pulpal inflammation and dentinal bridge formation were similar in all the experimental groups (P > 0.05). Dentinal bridge formation was similar in the MTA and Biodentine groups and was higher than in the propolis group. Continuation of dentinal bridge in the MTA group was significantly higher than that in the Biodentine and propolis groups (P < 0.05). Conclusion: MTA, Biodentine, and propolis are equally effective for DPC.

Background: MicroRNAs are a class of small noncoding ribonucleic acids that perform a critical role in adjustment of gene expression. miRNAs-155 (miR-155) participates in controlling inflammation. Periodontitis is defined as inflammatory disorder of tissues surrounding the teeth. In this study, the expression levels of miR-155 and its target genes, tumor necrotizing factor alpha (TNF-α), and interleukin-6 (IL-6) were evaluated in a group of Iranian patients. Materials and Methods: This sectional study was performed on 10 healthy controls and 10 individuals with chronic periodontitis by means of polymerase chain reaction (PCR) test. For each individual, clinical parameters including probing depth and clinical attachment loss and blood samples were measured. Levels of miR-155, TNF-α, and IL-6 were quantified using real-time PCR (α=0/05) and the results were analyzed by Mann–Whitney U test. Results: The level of miR-155 was significantly higher in patients with chronic periodontitis (P < 0.001). A positive correlation was observed between the level of miR-155 and clinical parameters (P < 0.05). Level of miR-155 in tissue samples was correlated with blood samples although the expression level was higher in blood samples. Conclusion: As the expression level of miR-155, TNF-α, and IL-6 genes was higher in subjects with chronic periodontitis than healthy individuals, it might suggest a role for miR-155 in patients with chronic periodontitis.

Crouzon syndrome is an autosomal dominant trait, leading to midface deficiency, undeveloped orbits, short nasal dorsum, and exophthalmos as the typical clinical features. Early correction of craniofacial problems can improve patients' quality of life, but many of these patients with Crouzon syndrome are seeking treatment in older ages when they are missed for multidisciplinary management and distraction technique in proper timing. Modified LeFort III osteotomy is one of the treatment options that can be used for proper resolution in adult patients. The present case report study aims to describe a patient with midface deficiency due to the Crouzon syndrome who has undergone a combination of modified LeFort III osteotomy with the periocular approach and LeFort I osteotomy, nasal dorsum augmentation accompanied by genioplasty, wholly as a single surgical procedure which has been shown that can result in highly satisfactory outcomes for both patient and surgeon.

Background: Dental implants are known as a widely accepted and predictable method to replace missing teeth. Many factors, including using a class of drugs, such as β-blockers, can improve the osseointegration of dental implants. This study aimed to investigate the relationship between administrating propranolol and osseointegration in dental implants. Materials and Methods: This experimental animal study was performed on four native male street dogs of 11–13 kg of weight and 16–20 months of age. The specimens underwent teeth extraction. After that, the dogs were randomly divided into two groups. The first group contains two control dogs which would receive oral saline. The second contains two dogs which would receive oral tablets of propranolol daily. After a period of healing, three titanium implants were inserted in each of speciments' left mandibular quadrant, and treatment was resumed with propranolol and saline administration in case and control group, respectively. After 4 weeks, one of control group dogs and one of case group were anesthetized, and dental implants were removed alongside the peripheral bone marrow using a trephine drill. Meanwhile, the other two dogs (1 control and 1 propranolol administered dogs) were anesthetized after 9 weeks of implant placement, and the same procedure was carried out. Results: Due to the histomorphometric assessment, the mean score of bone implant contact (BIC) in week 4 was significantly higher in case group compared to control one (68.33% vs. 20.22%). In week 9, the mean BIC score was higher in case group compared to control group (68.60% vs. 50.17%); meanwhile, in contrast to week 4, it was not statistically significant. In both case and control groups, the formation of woven and lamellar bone was more significant in week 4 rather than week 9. Conclusion: Administration of systemic β-blockers can improve dental implants osseointegration process.

Background: The reduction of Streptococcus mutans from the oral cavity or its adherence to tooth surfaces can prevent or decrease the progression of caries. In this study, the antimicrobial and anti-adherence properties of Pistacia atlantica (P. atlantica) resin (Essential oil [EO] and methanolic extract [ME]) were investigated on S. mutans strains. Materials and Methods: In this in vitro experimental study, the growth rate, biofilm formation ability, and antibiotic susceptibility profile of S. mutans ATCC35668 and 3 strains isolated from caries lesions were studied. The EO and ME of P. atlantica resin were prepared. The anti-bacterial and anti-adherence properties of them were evaluated using microdilution and microplate adherence tests, respectively. The data were statistically analyzed using SPSS with one-way and two-way analysis variance. Direct comparisons between the groups were made using the Wilcoxon W-Mann–Whitney U-test. Statistical significance was set at P < 0.05. Results: All target strains showed the same growth rate and antibiotic susceptibility profile and were found strongly adherent. Both EO and ME showed moderate anti-bacterial properties (growth reduction up to 47.1% and 39.1%, respectively) against S. mutans, while the anti-bacterial effect of EO was higher than ME, significantly (P < 0.05). In all tested concentrations, EO showed a significantly stronger anti-adherence activity (50%–80%) than ME. Conclusion: The results showed an anti-cariogenic effect of EO extracted from P. Atlantica resin. Considering that S. mutans adhesion is a necessary step in the beginning and progression of dental caries, this study can suggest the use of such extract in mouthwashes or toothpaste as an alternative agent for preventing bacterial attachment and biofilm formation.

Background: Accurate shade matching of metal-ceramic restorations with natural teeth is one of the most challenging aspects of dental restorations and esthetic dentistry. The aim of this study was to evaluate of the color parameters of two types of porcelain systems VMK Master and VM13 porcelain with VITA 3D-master shade guide. Materials and Methods: In this in vitro study a total of 56 metal discs (10 mm diameter and 2 mm thickness) were fabricated. Each of the disks was veneered with porcelain (Vita Zahnfabrik, Bad Sackingen, Germany) of the VITA shade. The discs were randomly divided into four groups (2M2 and 3M2 from VM13, 2M2 and 3M2 from VMK master) of 14 (n = 14). The spectrophotometer was used for taking color measurements based on the numerical color data of the CIELAB color system. Data analysis was performed by t-test (P < 0.05). Results: Comparison of color parameters in different porcelain showed that the type of porcelain caused a significant difference in color parameters (L, a, and b) (P < 0.05). The degree of translucency (L*) or glaze of VMK porcelains was higher than VM13, but the parameters a* and b* were higher in VM13 porcelains than VMK (P < 0.05). Furthermore, the color difference of two porcelain in 2M2 (1.63 ± 0.84) and 3M2 (1.71 ± 0.96) shades was within the acceptable clinical limit. Considering the total color difference (ΔE), there were no significant differences between the ΔE values produced by any of shades (P > 0.05). Conclusion: In the present study, the spectrophotometric analysis revealed that the porcelain shade type causes a change in the color parameters, but the color difference between two porcelains VMK and VM13 is within the acceptable range of clinical color. Therefore, both porcelain systems with 2M2 and 3M2 shades are suitable for enhancing the results of restorative dentistry.

Background: In Iran, the inequitable distribution of health-care staff, especially dental practitioners between rural and urban areas has a major impact on the delivery of care for those living in rural communities. This study investigated the factors affecting the retention of dental practitioners to stay in the rural areas. Materials and Methods: This is a cross-sectional study conducted in 2019. All dental practitioners working in health services centers covering a population lower than 20,000 people in Kerman province participated in this study (n = 81). A researcher-designed questionnaire was used for the data collection. The data were analyzed using the descriptive statistics and logistic regression through the SPSS software. Results: The mean age of the participants was 29.2 ± 6.5 and 39.5% were female. The results showed that about two-thirds of native dentists (with local origin), 73.3% of married dentists, and all dental practitioners who had no children or had a child under the age of six were willing to continue working with their current Comprehensive centers of health services compared to other dentists. Univariate and multivariate logistic regression showed that there was a significant relationship among dentists' age, monthly salary, and facilities available in the area (place of residence, availability of vehicles, etc.), view of dental practitioners on living in a rural area, and view of dentists' families on living and working in the area (p < 0.05). Conclusion: More than half of the dental practitioners declared their willingness to stay in rural areas, although, in practice, this amount of presence in rural areas does not meet the needs of residents. Financial issues, amenities, and facilities in the rural areas can have a positive impact on the retention of dental practitioners.

Background: The mechanical and thermal properties of polymethyl methacrylate, as the most commonly used material for the fabrication of dental prostheses, should be improved due to its structural weaknesses. The present study aimed to compare the flexural strength and thermal conduction of two heat-cured and self-cured acrylic resins reinforced with aluminum oxide nanoparticles. Materials and Methods: In this in vitro study, a total of 114 samples consisting of heat- and self-cured three subgroups (1% and 3% Al₂O₃ and the control) with 66 samples for the thermal conduction (n = 11) and 48 samples for the flexural strength (n = 8) tests were prepared. Flexural strength was assessed with a three-point bending test using a universal testing machine. One-way ANOVA was applied for data analysis, followed by post hoc Tukey paired group comparison tests (P < 0.05). Results: An increase in the aluminum oxide nanoparticle percentage in acrylic resins increased the thermal conduction in heat-cured acrylic resin from 2.142 ± 0.0298 to 2.487 ± 0.0359 m (2)/sec and in self-cured acrylic resin from 2.0150 ± 0.02646 to 2.1475 ± 0.04031 m (2)/sec and decreased the flexural strength in heat-cured acrylic resin from 60.521 ± 8.9278 to 49.747 ± 4.4729 MPa and in self-cured acrylic resin from 37.573 ± 10.9237 to 35.569 ± 6.1531 MPa (P < 0.05). Conclusion: The incorporation of aluminum oxide nanoparticles adversely affected acrylic resin flexural strength; however, it increased the thermal conduction.

Background: Considering the studies on the effects of bleaching materials on properties of dental materials, The aims of this in vitro study were to evaluate the effects of two different concentrations of bleaching agents on flexural strength and microhardness of VITA ENAMIC. Materials and Methods: In this experimental in vitro study, 30 rectangular-shaped specimens (2 mm width × 2 mm height × 12 mm length) for flexural strength and 30 specimens (5 mm width × 5 mm length × 2 mm height) for microhardness tests were prepared from VITA ENAMIC blocks 12 × 14 × 18 mm. The specimens were polished using silicon-carbide sandpapers 400, 600, 800, 1200, 2000 under flow of water for 60 s each. The prepared samples for flexural strength and microhardness were divided into 3 subgroups (n = 10): control group (C), samples bleached using Opalescence PF 15% (B15), and samples bleached with Opalescence Xtra Boost 40% (B40). Flexural strength measurement was done using a universal testing machine, and microhardness test was done using Vickers. Data were analyzed using analysis of variance and post hoc tests and P < 0.05 was considered significant. Results: The mean microhardness values of C, B15, and B40 groups were 255.46 ± 3.02, 249.86 ± 4.18, and 235.53 ± 4.61 kgf/mm². Opalescence PF 15% and Opalescence Xtra Boost 40% affected microhardness of ENAMIC significantly (P < 0.05). The mean flexural strength values of C, B15, and B40 groups were 155.26 ± 16.13, 142.14 ± 11.52, and 133.39 ± 16.13 MPa. A significant decrease in flexural strength was found between the C and B40 groups (P = 0.007). However, the difference between flexural strength of the C and B15 groups was not significant (P > 0.05). Conclusion: Our study showed that both concentrations of bleaching agents can affect microhardness of ENAMIC. Moreover, hydrogen peroxide 40% has a negative effect on the flexural strength of ENAMIC.

Background: Masking dark tooth structure or darkness of oral cavity with ceramic restorations is an important concern. The aim of this study was to determine the minimum thickness of a multilayer all-ceramic restoration (IPS-emax Press) required for a proper masking in these situations. Materials and Methods: In this experimental in vitro study, 36 multilayer ceramic disks of IPS e.max Press (IvoclarVivadent, Schaan, Liechtenstein) with the diameter of 13 mm were prepared and allocated in six groups of different core/veneer thicknesses: 0.4/0.4 mm (G1), 0.5/0.5 mm (G2), 0.6/0.6 mm (G3), 0.8/0.7 mm (G4), 1.0/0.8 mm (G5), and 1.1/0.9 mm (G6). For backgrounds, the standard black tile of spectrophotometer (B) was used to stimulate the darkness of oral cavity, and an opaque ceramic (OC) of IPS-emax Press (OC) was fabricated to determine the masking ability. CIELAB values of all disks on B and OC backgrounds were measured, and ΔE was calculated between two backings. One-way ANOVA and post hoc tukey test were used to analyze the data. ΔE ≤3.3 and P < 0.05 were considered, respectively, as the clinically acceptable limit and the level of statistical significancy. Results: The mean ΔE between B and OC of groups 4 (2.83 ± 0.80) and 5 (1.46 ± 0.36) were within the range of the clinically acceptable color difference (ΔE ≤3.3); thus these groups could properly mask the black background. A trend was existed in the results as by increasing the thickness, ΔE was decreased. Conclusion: A thickness of 1.5 mm of a multilayer ceramic restoration (IPS e.max Press) is required to mask a dark discoloration.

Background: Small chipping or fracture of ceramic restorations may be repaired by composite resin instead of replacing the restoration. This method is faster and cheaper compared to restoration replacement. Several strategies have been suggested to obtain a high repair shear bond strength (SBS). This study aimed to assess the efficacy of some new ceramic surface treatments (laser and universal adhesive) to enhance the repair bond strength of composite resin to ceramic compared to the conventional method. Materials and Methods: This in vitro study evaluated 80 IPS Empress Esthetic ceramic plates in eight groups (n = 10). The ceramic surface was polished with 320-grit silicon carbide paper under running water, rinsed with water spray for 10 s and dried. The samples were then divided into two subgroups for mechanical surface preparation with hydrofluoric (HF) acid and Er: YAG laser (2 W, 200 m J, 10 Hz, 10 s). Each group was divided into two subgroups for use/no use of silane. The conventional or universal adhesive was then applied on the samples in each subgroup. Composite cylinders were bonded to the ceramic surface using plastic tubes. The samples were stored in distilled water at 37°C for 24 h and subjected to an SBS test. Data were analyzed using one-way ANOVA (P < 0.05). Results: The interaction effect of variables on SBS was significant. Maximum SBS was noted in HF acid + silane + conventional adhesive group (mean: 12.0481 MPa). Minimum SBS was noted in the laser + conventional adhesive group (mean: 2.5766 MPa). Surface treatment with HF acid yielded significantly higher SBS than laser (P < 0.001). The interaction effect of conventional/universal adhesive and use/no use of silane on SBS was statistically significant. Conclusion: The repair SBS was higher in groups treated with HF acid compared to laser. Ceramic surface treatment with HF plus silane plus conventional adhesive yielded a higher SBS as well as HF plus Universal adhesive. Thus, the application of silane as a separate step can be omitted in the repair of ceramic restorations with universal adhesives.

The white spot lesion on the dental enamel is an optical alteration that compromises the esthetics of smile. It can be caused by many factors, among them, defects in mineralization and formation of tooth enamel. Resin infiltrants are agents that penetrate, by capillarity, through the pores of the demineralized or hypomineralized enamel, altering the refractive index (RI) of the tooth structure and totally or partially masking the appearance of the white spot. The aim of this work was to report the use of resin infiltration to minimize the visualization of white spot lesion, present in an upper central incisor, as a microinvasive approach for the esthetic treatment of deep enamel hypomineralization. A 20-year-old female patient sought care with the esthetic complaint of extensive white spot lesion on the buccal face of her upper right central incisor. The diagnosis established was a deep white stain associated with the incisor molar hypomineralization syndrome, and the treatment of choice for the resolution of the case was the application of the Icon^® resin infiltrant (DMG, Hamburg, Germany). To reach the body of the lesion, three cycles of acid erosion, using 15% HCl, were necessary to obtain a satisfactory aspect of masking the white lesion. A camouflage effect of the deep white spot lesion was achieved with the use of the resin infiltration, without the need of additional and irreversible wear of the dental structure.

Background: To compare and evaluate the strength rendering capacity of three restorative materials in tooth model simulated as immature teeth. Materials and Methods: In this in vitro study, 80 human maxillary permanent central incisors scheduled for periodontal extraction were collected, and an immature tooth model was prepared using a 3 mm twist drill. To simulate single-visit apical barrier, all the teeth were prepared with peso number 1–6. The teeth were segregated into three experimental and a control group. The experimental groups (n = 20) comprised of fiber-reinforced composite (FRC), Biodentine, and glass ionomer cement. The fracture resistance of all the teeth was tested using universal testing machine. The final reading of the applied load to cause fracture was noted and later was subjected to statistical analysis, P ≤ 0.05 was considered statistically significant, and the level of significance was fixed at 5%. Student's t-test was applied to compare values among experimental groups Results: There was a significant difference in the values of peak load resulting in fracture among experimental groups which was observed statistically (P ≤ 0.001). FRC exhibited superior reinforcing capacity (mean: 1199.7 N) among the experimental materials followed by Biodentine and Bioglass R. The lowest value to fracture was observed in control group (mean: 236.7 N). Conclusion: The results indicate that FRC could substantially contribute positively in reinforcing the simulated thin-walled immature roots.

Background: To compare the effect of different mouth washes on metallic ions release from silver-soldered and laser-welded orthodontic attachments. Materials and Methods: In this comparative in vitro study, 32 samples of molar bands without attachments were used. Sixteen samples were silver soldered to stainless steel (SS) wire and 16 samples were laser welded using laser welding device to SS wire. Each group samples were divided into four test groups and submerged in solution containing sodium fluoride (NaF), NaF + alcohol (NaF + alcohol), Chlorhexidine (CHX), and artificial saliva (AS). Samples were shaken for 24 h with an agitation rate of 60 rpm. One sample from each group was selected to study the morphologic changes on their surfaces through scanning electron microscopy (SEM), and remaining samples were studied for metal ions released and dissolved in the solutions using spectrometry. The metal ions release values of two different attachment methods in three different mouth washes and AS group were compared using the unpaired t-test. A two-way analysis of variance was used to identify the significant differences between the two types of orthodontic attachments immersed in four different types of solutions. P < 0.05 was defined to be set significant for all tests. Results: Level of metal ions released from the samples of silver soldering was higher than from laser welding. The lowest amounts of metal ions were released in CHX while highest in NaF + alcohol. The SEM images were in accordance with these findings. Conclusion: Laser welding should be preferred over silver soldering for the construction of orthodontic appliances. CHX containing mouthwashes such as Hexidine can be prescribed for the patients undergoing orthodontic treatment. More in vivo experiments will determine whether the levels of dissolved nickel ions can reach the toxic or sub-toxic concentrations or not.

Background: During the first experiences of clinical treatment, dental students face various challenges. The purpose of the study is to standardize the questionnaire as a suitable tool for quantitative and qualitative evaluation of psychosocial impact, stress levels, and learning effect of dental students during the transition from preclinical to clinical education in Persian. Materials and Methods: In this cross-sectional study a questionnaire including three areas of psychosocial impact, perceived stress, and learning effect was systematically translated. In the group of experts, face validity was examined. Then, the content validity ratio (CVR) and the content validity index (CVI) were determined. The reliability of the questionnaire was determined by the test–retest method and the Cohen's Kappa coefficient. In a cross-sectional study, the psychosocial impact, stress levels, and learning effect of all students newly admitted to the endodontic, prosthetics, periodontics, and restorative dentistry departments of Shahid Beheshti Dental School (128 people) were measured. Mann–Whitney and Spearman–Rho were used for statistical analysis (P = 0.05). Results: During the CVR and CVI evaluation, 12 statements were removed from the questionnaire, and one statement was changed. All valid statements of the questionnaire were considered reliable. The initial questionnaire was finally developed in the form of 27 items. Interest in clinical treatment and collaboration between students and faculty had the greatest psychosocial effects. The highest level of stress among students was seen in the endodontic ward (mean = 3.8). The greatest effect of learning was seen in different sections in infection control (mean >4). Conclusion: This study provided a standardized tool in Persian to evaluate the psychosocial impacts, perceived stress, and learning effect of dental students during the transition to clinical education and focused on the first clinical treatment experiences. One important psychosocial factor was collegiality between teachers and students. The ability to communicate well with the patient is thought to reduce stress.

Background: To establish an endodontic diagnosis, a clinician should consider a variety of factors. Various studies have failed to demonstrate a strong correlation between histological findings with clinical and radiographic assessments. This study sought to evaluate the histopathological features of reversible and irreversible pulpitis diseases and their correlation with clinical diagnosis in extracted human molar teeth. Materials and Methods: In this experimental ex vivo study, 75 molars with caries and three intact molars were used. According to the radiographic findings and clinical criteria and the need for root canal therapy, samples were categorized as having normal/reversible pulpitis and irreversible pulpitis. Immediately after extraction, an exposure was made at 2 mm below the cementoenamel junction. Formalin-fixed specimens were decalcified, sectioned and stained with hematoxylin and eosin for histological examinations using light microscopy. Variables including the type and severity of the inflammation, hyperemia, necrosis, fibrosis and the existence of an odontoblastic layer and dentin bridge were evaluated. The Fisher's exact test and the Chi-squared test were used for statistical analysis. P <0.05 was considered as significant. Results: Acute inflammation, hyperemia and pulp exposure were significantly more common among subjects with irreversible pulpitis (P < 0/005). However, fibrosis was significantly higher in the reversible group (P < 0/005). There were no statistically significant differences between the groups regarding the other variables. Conclusion: Some discrepancies between clinical, radiographic and histological findings were observed in our experimental study. Indeed, effective clinical practice requires consideration of all discrepancies found.

Background: This study aimed to assess the oral health knowledge, attitude, and performance of the parents of autistic 3–12-year-old. Materials and Methods: This descriptive cross-sectional study evaluated 50 parents of autistic 3–12-year-old in Isfahan city. The oral health knowledge, attitude, and performance of the parents were evaluated using a self-administered questionnaire with closed questions, after confirming its validity and reliability. Data were analyzed using independent t-test, one-way ANOVA, Pearson's correlation coefficient, regression analysis, and Cronbach's alpha (α =0.05). Results: Of children, 32 (64%) were males and 18 (36%) were females. A total of 28 (56%) fathers and 22 (44%) mothers participated in this study. The mean age of the children and parents was 8.12 ± 2.4 years and 39.6 ± 6.8 years, respectively. The mean age at the time of diagnosis of autism was 4.08 ± 1.33 years. Of all children, 24 (46.2%) had a previous dental history. The mean scores of the knowledge and attitude of the parents were 5.2 ± 1.7 out of 11, and 16.1 ± 3.1 out of 30, respectively. Of demographic variables, order of child birth had a significant correlation with attitude of the parents, and those with one single child had significantly higher attitude score (P = 0.03). Conclusion: The oral health knowledge, attitude, and performance of the parents of autistic children in Isfahan city were lower than expected, which calls for knowledge enhancement strategies in this respect.

Background: This study aimed to compare the antimicrobial effects of green tea, microwaving, cold boiled water, and chlorhexidine (CHX) on Streptococcus mutans and Candida albicans on silicone pacifiers. Materials and Methods: In this in vitro experimental study, 60 equal-size samples of silicone pacifiers were cut, ultraviolet sterilized, and randomly divided into two groups (n = 30) for immersion in 0.5 McFarland standard suspension of S. mutans and C. albicans. The samples in each group were then randomly divided into five subgroups (n = 6) for disinfection with 0.12% CHX, cold boiled water, green tea, microwaving for 7 min, and distilled water. The sample suspensions were cultured on blood agar (for S. mutans) and Sabouraud dextrose agar (for C. albicans) and incubated. The number of colonies was counted after 24 and 48 h. Data were analyzed using the Kruskal–Wallis and Mann–Whitney tests (P < 0.05). Results: At 24 and 48 h, the S. mutans colony count was the lowest in CHX and green tea subgroups followed by microwave, cold boiled water, and distilled water subgroups (P < 0.05). Conclusion: CHX and green tea can significantly decrease the S. mutans and C. albicans colony count on silicone pacifiers.

Background: One of the critical factors determining the success of dental implants is primary stability. This study aimed to determine the density of jawbones in the implant candidate sites via cone-beam computed tomography (CBCT) and its correlation with the values obtained from resonance frequency analysis during surgery. Materials and Methods: In this descriptive-analytic study seventeen implant sites requiring implant placement were selected. Impressions were sent to the laboratory to construct a surgical guide via the stereolithographic method. An electronic surgery was performed on the chosen implant sites according to each patient's CBCT information entered into the Kaveh surgical guide software. The bone density of the target areas was calculated using the gray value (voxel value). After preparing the final osteotomy, an implant was installed in the area according to the manufacture's recommendation. The relevant Osstell^® SmartPeg was selected and installed on the implant body to determine the primary stability. Kolmogorov–Smirnov test and the correlation pearson correlation statistical test. used for statistical analyze. P value amounts < 0.05 was considered significant. Results: The mean and standard deviation of the gray scale in this study were 563.7 ± 218.8 and 65.3 ± 7.7 implant stability quotient (ISQ) respectively. The correlation between gray scale and ISQ was evaluated by the Pearson correlation test, and the results indicated a strong correlation between the two variables. Conclusion: The voxel value and primary stability had a normal distribution and strong correlation. In other words, the gray scale determined by CBCT imaging techniques at the proposed implant site could be used to assess the bone density before the surgery.

Background: Adverse pregnancy outcome is due to deviation from the normal physiological and immunological process. There is conflicting evidence in support of maternal periodontitis as a risk factor for preterm low birth weight (PTLBW). Thus, the aim of the present study is to evaluate the correlation between PTLBW and periodontitis in postpartum mothers based on clinical and microbiological parameters. Materials and Methods: An observational retrospective study was conducted. A total of 103 women with singleton births were included in the study, which was divided into two groups, i.e., Group I-PTLBW and Group II-normal term normal birth weight (NTNBW). Clinical parameters such as oral hygiene index simplified, gingival bleeding index (BOP %), periodontal probing depth (PPD) and and clinical attachment loss (CAL) were recorded on the next day of postpartum. Two samples from each group, i.e., placental extract and the subgingival plaque were collected and transported to the laboratory in an anaerobic medium for microbiological analysis. The statistical analysis was performed using an unpaired t-test and Wilcoxon Mann–Whitney U-test. The P < 0.001 was considered statistically significant. Results: PTLBW group showed significantly higher amounts of periodontal destruction in terms of clinical parameters. The pathogens were also in higher quantities in the PTLBW group compared to the NTNBW group. Conclusion: Periodontitis is related to PTLBW in pregnant women of the studied population. Maternal oral hygiene status delivering PTLBW babies are compromised compared to mothers delivering NTNBW babies. Hence, periodontitis during pregnancy phase is an important health concern for the growing fetus.

Background: It is unclear which the material is a better choice for post and core rehabilitation systems in endodontically treated teeth. This study aimed to compare the fracture resistance of three different postcore systems. Materials and Methods: In this in vitro study, 33 extracted premolars were treated endodontically and divided into three groups, namely (A) the prefabricated fiberglass postcomposite core, (B) the Ni-Cr cast postcore, and (C) the polyetheretherketone (PEEK) postcore groups. After postcementation, the core was restored with Ni-Cr crown. By a universal testing machine, the fracture resistance of the posts was assessed. Furthermore, types of fractures were determined with radiography and confirmed objectively by cutting the acryl resin boxes. The data of the fracture resistance were analyzed using the one-way ANOVA and Tukey test, and the data of the fracture pattern were analyzed using Fisher's exact test (P < 0.05). Results: The fracture resistance was significantly higher in Group B (Ni-Cr) than in Group C (PEEK) (P = 0.001) and Group A (fiberglass) (P < 0.001). Moreover, the fracture resistance was higher in Group C (PEEK) than in Group A (fiberglass) but was not statistically significant (P = 0.405). The fracture pattern was different in all the groups based on the types of fracture (P = 0.009) and the repairability of fracture (P = 0.036). Conclusion: The present study showed that the fracture resistance was significantly higher in the Ni-Cr post than in the fiberglass and PEEK posts. Further, the fracture mode was more repairable in teeth restored with the PEEK post, as compared to the other posts.

Background: Because of the importance of the condyle, it is crucial to document all changes in its position after orthognathic surgery. Since previous studies in this regard are mostly controversial and limited by two-dimensional radiography technique, this study was conducted. Materials and Methods: This prospective clinical trial was performed on 102 measurements (17 patients, 2 condyles each, and 3 time points). Cone-beam computerized tomography imaging was done for 17 skeletal Class-III patients (10 females and 7 males, mean age, 24.05 ± 4.78 years) undergoing fixed orthodontic treatment, at three time points T0 (before surgery), T1 (immediately after surgery), and T2 (8 months after surgery). Condylar positions were measured. Position changes were evaluated during the course of the study. They were also compared between right/left sides and between men and women. Tests in use were repeated-measures one- and two-way analysis of variance and paired t-tests (α =0.05, α =0.017). Results: Alterations in various anatomical condyle parameters over the 8-month course of the study did not reach the level of significance (P ≥ 0.078). At all intervals, mean anterior-posterior index (API) remained between −12 and +12 (indicative of central position of the condyle in the glenoid fossa). Between men and women, left superior joint space, left anterior joint space, and left API differed (P ≤ 0.05). Left condyle mean superior joint space and anterior joint space were greater in men compared to women in all the three intervals; left condyle mean API was greater in women compared to men (more posterior in men, P ≤ 0.05). Conclusion: Condyles might not change significantly after 8 months post-surgery. However, small changes might be observed, and these changes might differ between the left and right sides and between males and females.

Background: This study aimed to evaluate the amount of bone regeneration in critical defects of rabbit calvaria filled with magnesium- and strontium-doped bioactive glasses. Materials and Methods: In this rabbit critical-size calvarial defects study, 12 male New Zealand white rabbits were randomly divided into two groups. On the calvaria of each rabbit, four lesions (two lesions in the frontal bone and two lesions in the peritoneal bone) were created with a diameter of 8 mm spaced apart. Each lesion was filled in with (1) strontium-doped bioactive glass, (2) magnesium-doped bioactive glass, (3) 45S5 bioactive glass, and (4) empty lesion (control). Six rabbits were sacrificed at the end of 4 weeks, and six rabbits were randomly sacrificed at the end of 8 weeks. Bone sections with a 5-μ thickness of rabbit calvary bone were prepared, and the percentage of new bone, connective tissue, and residual material were calculated in microscopic images. Statistical analysis was performed by two-way ANOVA and Bonferroni additional tests, and the level of significance was set at P < 0.05 in all categories. Results: At 4 weeks, magnesium-doped bioactive glass showed the highest new bone formation with a mean of 11.66 ± 2.64, followed by the strontium-doped bioactive glass with the mean of 11.10 ± 1.69 (P = 0.0001). While at week 8, the highest amount of new bone observed in the strontium-doped group with a mean of 28.22 ± 3.19, and then, the magnesium-doped bioactive glass with a mean of 22.55 ± 3.43 (P = 0.0001). Conclusion: Doping strontium and magnesium in the structure of bioactive glasses increases new bone regeneration in comparison with 45S5 bioactive glass.

Background: Proliferation markers have been used to determine the behavior and prognosis of benign and malignant tumors; this study was aimed to compare the immunohistochemical (IHC) expression of proliferating cell nuclear antigen (PCNA) and novel marker minichromosome maintenance complex component 7 (MCM7) in common salivary gland tumors including pleomorphic adenoma (PA), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (AdCC), to find a possible significant correlation between benign and malignant tumors. Materials and Methods: In this cross-sectional study, a total of 90 cases, including 30 PAs, 30 MECs, and 30 AdCCs, were collected. The IHC expressions of PCNA and MCM7 were evaluated. Their expressions were compared with each other and between benign and malignant tumors. Statistical analysis was performed by Chi-square and Tukey's test. P value was considered 0.05. Results: Out of 30 cases of PA, 28 cases (93.3%) were PCNA positive and 28 cases (93.3%) were MCM7 positive. In the AdCC cases, 29 cases (96.6%) were PCNA positive and 29 cases (96.6%) were MCM7 positive. In the MEC cases, all cases (100%) were PCNA positive and 23 cases (76.6%) were MCM7 positive. The labeling index (LI) of MCM7 and PCNA was evaluated, and this index was lower in MCM7 LI than PCNA in all tumors. The MCM7 and PCNA expression showed a significant difference in PA and MEC (P < 0.001). Conclusion: PCNA expression was higher than MCM7 expression in salivary gland tumors. However, more studies are needed to evaluate the malignant activity of these tumors with group of markers such as MCM family members.

Background: Since salivary and breast glands are both considered as a tubulo-acinar, exocrine glands, and they have a common neoplastic morphology, it is not surprising if they share a similar molecular mechanism responsible for their neoplastic transformation. From the first description of estrogen receptor-α (ER-α) in salivary tumors, tremendous attentions have been attracted to this receptor for evaluating its impact in mucoepidermoid carcinoma (MEC). Materials and Methods: In this descriptive analytics, 28 samples of MEC (14 high grade and 14 low grade) were collected from the Oral and Maxillofacial Pathology Department of Isfahan Dental School and Isfahan Alzahra Hospital. All of these samples were stained with immunohistochemical technique with ER-α marker. The expression of the receptor was evaluated by two oral and maxillofacial pathologists. Statistical data were saved at SPSS and had been analyzed by Mann–Whitney U- and independent t-tests (significance level: P ≤ 0.05). Results: The high-grade MEC was more common in patients with a higher average age (55.9); on the other hand, low-grade MEC was mostly observed in those with a mean age of 39.2 years. Moreover, high-grade MEC was more prevalent in men rather than in women. The staining intensity distribution average in high-grade MEC and low-grade MEC was 2.4 and 0.8, respectively (P = 0.48). Conclusion: The expression of ER-α in high-grade MEC was significantly more than low-grade MEC, indicating that targeting this receptor alongside surgery could bring more advantages for patients.

Background: Remifentanil is a short-acting synthetic opioid, seems to facilitate hospital discharge, induce less agitation and better recovery quality. The aim of this study was to investigate the effects of remifentanil on the quality of recovery among healthy children who were candidate for dental procedures under general anesthesia. Materials and Methods: This study was a double blind randomized controlled clinical trial on healthy children who referred to the Department of Pediatric dentistry, School of Dentistry, Isfahan University of Medical Sciences. Both groups were anaesthetized using 5 mg/kg thiopental sodium, 1 μg/kg fentanyl and 0.6 μg/kg atracurium. The first group received propofol to maintain anesthesia and the second group was given remifentanil along with propofol. Then, the time span to regain consciousness, level of agitation during recovery and time of discharge were monitored and compared between the two groups. Data were analyzed using the Mann-Whitney U-test, and the Kruskal–Wallis test at P < 0.05 level of significance. Results: Findings showed that the propofol + remifentanil group recovered faster than the propofol group. Chi-square test showed a significant difference in recovery time between the two groups (P < 0.05). About 45 min after regaining consciousness, the mean pediatric anesthesia emergence delirium score in the propofol group was 4.02 ± 2.19 and was significantly higher than the propofol + remifentanil group (3.02 ± 2.83) (P < 0.05). In addition, the mean Postanesthetic Discharge Scoring System score in the propofol group was 6.04 ± 1.74 and was significantly higher than the propofol + remifentanil group (7.58 ± 2.14) (P < 0.05). Conclusion: Combination of propofol and remifentanil significantly reduced the time taken for recovery, discharge and agitation level compared to propofol.

Background: This study aimed to compare the antibacterial effects of calcium hydroxide, curcumin, and Aloe vera as an intracanal medicament on 6-week-old Enterococcus faecalis biofilm. Materials and Methods: In this in vitro study, the solution containing E. faecalis ATCC^® 29212^™ was inserted into the canals of 72 single-rooted teeth to produce biofilm. The samples were divided into four groups, and the antibacterial agent as an intracanal drug was used for 1 week. Calcium hydroxide, curcumin, and A. vera were used as intracanal medicaments in three groups, respectively, and the fourth group was irrigated with normal saline. The collected debris was cultured by spread plate method for the bacterial count by colony count machine, and the number of bacteria in each sample per ml was reported in colony-forming unit per ml (CFU/ml). The data were analyzed using SPSS software. KruskalWallis and MannWhitney U-tests were used for comparison of CFU/ml between the study groups. P <0.05 was considered significant. Results: The mean CFU/ml in the groups of calcium hydroxide, curcumin, and A. vera were 749.44, 630.55, and 1529.16, respectively. Compared with the control group, curcumin, calcium hydroxide, and A. vera showed 99.5%, 99.41%, and 98.79% antimicrobial effects, respectively. All three groups were significantly effective than the control group (P = 0.023, P = 0.023, and P = 0.024, respectively) but were not significantly different from each other (P = 0.057). Conclusion: All three groups showed significant antibacterial activity compared to the control group, curcumin had the most significant effect, followed by calcium hydroxide and A. vera. Therefore, herbal materials can be considered safe alternatives to synthetic medicaments for intracanal usage.

Osteoblastoma (OSB) is an uncommon (3% of benign and 1% of all) primary bone neoplasm with extremely rare occurrence in head and neck, especially the maxillary bone region. OSB of the jaw mainly involves the mandible bone. We report a 10-month-old male who was admitted to the hospital because of a mass in the right maxillary jaw region. Clinicoradiopathologic features of the patient have been described. The histological examinations revealed OSB of the maxillary bone. Total surgical resection of the tumor was performed with 10 months of follow-up and there is no evidence of recurrence. To the best of our knowledge, it is the first report of maxillary OSB in an infant.

Background: There is generally a lack of compliance in patients who report with oral candidiasis, as they are advised to temporarily stop wearing the prosthesis and are prescribed topical antifungals which are generally unpleasant to taste and follow a rigorous schedule. Furthermore, with the alarming evidence of drug resistance, there is a need for an enhanced drug and drug delivery system. The aim of the study was to determine the dose-dependent antifungal efficacy of silver-zinc zeolite nanoparticles (SZZ-NPs) when incorporated in two brands of soft denture liners against Candida albicans. Materials and Methods: A total of 72 samples were made to determine the in vitro antifungal efficacy of SZZ-NPs and fluconazole by measuring the mean inhibition diameter (MID). Two concentrations of SZZ-NPs were compared (0.5%, 2% w/w) with fluconazole 5%w/w which is routinely prescribed. The antifungals were incorporated in two types of commercially available soft denture liners (Visco gel, GC soft denture liner). The MIDs were measured at day 1, day 7, day 15, and day 30. The values obtained (P < 0.001) were analyzed with one-way ANOVA, Tukey's post hoc, and independent t-test. Results: A statistically significant difference (P < 0.001) was noted among all the antifungal agents at all the time intervals tested. The anti-fungal efficacy of SSZ-NPs 2% w/w incorporated in GC soft denture liner was significantly superior (P < 0.001) to all groups tested and it retained its antifungal efficacy even on day 30 (MID: 18.33 ± 2.44). Conclusion: SZZ-NPs 0.5%w/w, 2%w/w, and fluconazole 5%w/w can be incorporated with soft denture liners against C. albicans. Fluconazole 5%w/w is the recommended choice for short-term antifungal efficacy, while SZZ-NPs 2%w/w is recommended when long-term antifungal efficacy is needed. GC soft denture liner was the recommended choice.

Background: Oral diseases and their impact on health and quality of life have now evolved into a polarized epidemiological state in which their incidence is especially affecting the most vulnerable in the population: the elderly, especially those with low incomes economical. On the other hand, the noticeable increase observed in the proportion of older adults in developing countries such as Iraq during the last decades. Such a high proportion of older adults is causing an increase in their stomatological care needs that necessitate dentists to know precisely both the etiological factors, such as the pathogenesis and factors that determine the specificity of oral disorders at this stage of life. Only with this knowledge will professionals be able to face these patients with a modern dentistry based on prevention. The objective of the study was to show the impact of oral health on the quality of life of older adults in Iraq. Materials and Methods: A cross-sectional study was conducted in Iraqi adults focused on demographic characteristics factors, lifestyle, the Geriatric Oral Health Index, and Oral Health Diagnosis. Data were evaluated using ratios, the Chi-square analysis for the correlation among factors and odds ratios to verify statistical significance at P ≤ 0.05. Results: This research confirms the impact of oral health on the quality of life of older adults in Iraq. Endodontic problems compromise the quality of life of older adults. Conclusion: Oral health problems, especially those of traumatic, endodontic, and periodontal origin, negatively affect the quality of life of older adults in Iraq.

Background: Control of pain, fear, and anxiety of pediatric dental patients is a common concern for the parents and dental clinicians. This study aimed to compare the efficacy of audiovisual distraction (AVD) and mute-video distraction (MVD) for reduction of pain and anxiety of pediatric dental patients. Materials and Methods: This randomized split-mouth crossover clinical trial evaluated 60 systemically healthy children between 4 and 7 years requiring bilateral pulpotomy of primary maxillary first molars. The samples were randomly divided into 6 groups based on the distraction technique and sequence of its receipt: (I) control-AVD, (II) AVD-control, (III) control-MVD, (IV) MVD-control, (V) AVD-MVD, and (VI) MVD-AVD and were treated. The severity of pain and anxiety of patients during anesthetic injection was measured using physiological (pulse rate [PR]), sound, eyes, and motor (SEM) and faces pain rating (FPR) scales. Data were compared between Groups 1 and 2, 3 and 4, and 5 and 6 using crossover clinical trial analysis (P = 0.05). Results: The increase in PR and the mean FPR and SEM scales during anesthetic injection was significantly smaller in AVD than MVD (P < 0.05). No significant difference was noted between MVD and control technique regarding PR and mean FPR or SEM (P = 1.00). Conclusion: It appears that MVD has no significant efficacy for reduction of pain and anxiety of pediatric dental patients. AVD, however, can effectively decrease the pain and anxiety of pediatric dental patients during anesthetic injection.

Background: The effect of different intracanal medicaments on root fracture resistance has not been thoroughly investigated in the short and long term. To assess the effect of calcium hydroxide (CH), CH combined with Chlorhexidine (CHX), double antibiotic paste (DAP), and simvastatin as intracanal medicaments on the fracture resistance of the human root. One hundred and twenty single-rooted mandibular premolars which were extracted for periodontal reasons were collected for this in vitro study. Materials and Methods: This was an in vitro study. All teeth were decoronated. Root canals were prepared by the Pro taper system, and %2.5 NaOCl was used for irrigation. The smear layer was removed using %5.25 NaOCl and 17% ethylenediaminetetraacetic acid each for 3 min. The samples were randomly divided into five groups based on the medicament: (1) CH (2) CH + CHX (3) Simvastatin (4) DAP (5) Control group. All specimens in each group were incubated for 1 week (Subgroup A) and 1 month (Subgroup B). Then, medicaments were removed and filled with gutta-percha and AH26 sealer. All samples were tested for fracture resistance. The data were statistically evaluated with the SPSS software 17. ANOVA and Mann–Whitney U and Wilcoxon tests were used for the analysis of the data. P = 0.05 was considered statistically significant. Results: Although CH and CH + CHX increased the fracture resistance in a 1-week period, there was no significant difference between the groups after 1 month. Conclusion: Under the limitations of this study, CH and CH + CHX, DAP and simvastatin do not have a negative effect on root fracture resistance when used as intracanal medicaments for <1 month.

Background: The associations between Helicobacter pylori and human papillomavirus (HPV) with head and neck squamous cell carcinomas (HNSCCs) are approved before. However, the association between demographic, clinicopathological, and histologic characteristics of HNSCC patients and molecular detection of HPV and H. pylori has not been enough investigated. Materials and Methods: In this cross-sectional study, 62 patients with HNSCC from January 2016 to February 2020 were entered the study. For H. pylori detection 16S ribosomal RNA and glmM genes and HPV detection, MY09 and MY11 genes were used. P < 0.05 is considered as significant level. Results: There were 34 patients with advanced-stage cancer (54.8%). Grade I patients (61.3%) had the highest frequency. There were 20 (32.25%) and 7 (11.29%) patients with positive H. pylori infection among tumor tissue and healthy tissue margins, respectively. Positive HPV infections were in 8 (12.90%) and 3 (4.83%) patients, respectively, in tumor tissue and healthy tissue margins (P = 0.01). There was a significant difference between histological grade and infection to HPV among HNSCC patients (P = 0.01), and most of the positive HPV cases had well-, moderate-, and poorly-differentiated tumors, respectively. Our study showed a significant increase in HPV infection in the advanced-stage group compared to the early-stage group (P = 0.05). Conclusion: Our study findings concluded a significant relationship between HPV infection in HNSCC patients with age, stage, and grade. In summary, our findings based on polymerase chain reaction analysis concluded remarkably a potential role of HPV infection and to some extent H. pylori infection into the contribution of HNSCC malignancies.

Background: Cone-beam computed tomography (CBCT) has the highest sensitivity and specificity for the detection of vertical root fractures (VRFs). This study aimed to compare the diagnostic accuracy of CBCT with different gamma values for the detection of VRFs. Materials and Methods: In this in vitro, experimental study, multiplanar CBCT scans were obtained from 61 extracted premolars with prefabricated titanium posts using NewTom CBCT scanner. Next, VRFs were artificially induced in all teeth with a mallet, and the teeth underwent CBCT with three different gamma values. The images were evaluated by two observers twice with a 2-week interval for the presence/absence of VRFs. Data were analyzed using the kappa coefficient, McNemar test, and Chi-square test. The sensitivity, specificity, and overall accuracy of CBCT with different gamma values for the detection of VRFs were assessed by receiver operating characteristic curve. The level of significance was lesser than 0.05 (P < 0.05). Results: Changing the gamma value did not change the sensitivity, specificity, or accuracy of CBCT for the detection of VRFs. No significant difference was noted between the two observers in the detection of VRFs on CBCT scans taken with different gamma grades. The inter- and intra-observer agreement were excellent for all gamma grades. Conclusion: Any gamma value preferred by the observer can be used for the detection of VRFs on CBCT scans.

Background: Applying silver diamine fluoride (SDF) is recommended to arrest and prevent dental caries. However, it may jeopardize the bond of the restorative materials to the tooth. The aim of the present in vitro study was to evaluate the effect of the simultaneous use of the SDF and potassium iodide (KI) on shear bond strength to the sound dentin. Materials and Methods: In this in vitro study, on the buccal and lingual surfaces of the 48 human third molar teeth, dentinal surfaces with a diameter of 6 mm were created by removing the enamel. Then, the specimens were divided into four groups based on applying or not applying the KI/SDF and adhesive type (etch and rinse [E and R] or universal adhesive). Afterward, cylindrical composite restoration was made on the surfaces. Half of the specimens were subjected to 1000 cycles of thermocycling. Subsequently, the shear bond strength was evaluated by Universal testing machine. Furthermore, the type of failure was determined by a stereomicroscope. Data were analyzed by t-test and Chi-square at a significance level of P < 0.05. Results: There were statistically significant differences in shear bond strength between Groups 1 and 3 (P < 0.05), whereas the bond strength difference between Groups 2 and 4 was not statistically significant (P = 0.609). Failures were predominantly of the mixed type in almost all groups. Conclusion: Based on the results of this study, the superiority of shear bond strength of universal adhesive to the sound dentin compared to E and R adhesive was confirmed. Thus, using this type of adhesive is recommended under the condition that KI/SDF anticaries material is applied.

Background: One of the main reasons for the failure of root canal treatment is the incomplete knowledge of the root canal system. With respect to the complexity of maxillary molars root canal system, and the possibility of the relationship between the buccolingual width of the mesiobuccal root and root canal morphology in maxillary molars, the aim of this study is to determine this relationship with cone-beam computed tomography (CBCT). Materials and Methods: This in vitro study carried out on 311 CBCT scans. Maxillary first molars (n = 311) were evaluated in three sagittal, axial, and coronal planes. For each tooth the number of canals, presence of second mesiobuccal (MB2), buccolingual width of mesiobuccal root at the cementoenamel junction (CEJ), and mid-root level, and type of canals according to the Vertucci's classification were determined. Results: The results showed that 49.1% of first maxillary molars had 3 and 50.8% had four root canals. The most common canal type in the mesiobuccal root was Vertucci's Type I followed by Types II, IV, and V. The prevalence of MB2 in the Iranian subpopulation was 50.1%. In maxillary first molars with MB2, the buccolingual width of mesiobuccal root at the CEJ and mid-root level (P < 0.001) was significantly greater than the corresponding values in other one without MB2. Conclusion: The results showed that the buccolingual width of mesiobuccal root in maxillary first molars at the CEJ level and mid-root was correlated with the number of root canals.

Background: Stem cells from human exfoliated deciduous teeth (SHEDs) can transform into odontoblasts in vitro and in vivo. The role of 1α, 25-dihydroxyvitamin D3 (1α,25 vitD3) has been reported in the mineralization of hard tissues and teeth, as well as osteoblastic differentiation. This study aimed to assess the effect of different concentrations of 1α,25 vitD3 on odontogenic differentiation of SHEDs. Materials and Methods: In this experimental study, second-passage SHEDs were exposed to odontogenic medium along with 0, 10, 50, 100, and 150 nmol concentrations of in 1α, 25 vitD3 to determine its optimal concentration for odontogenic differentiation. The methyl thiazolyl tetrazolium (MTT) assay was performed. Odontogenic differentiation was evaluated by QRT- polymerase chain reaction for dentin matrix protein (DMP1) and dentin sialophosphoprotein (DSPP) genes. Morphology of differentiated cells was studied by Scanning Electron Microscopy. Data were analyzed using the Kruskal–Wallis, Mann–Whitney, Friedman, and Chi-square test. P < 0.05 is considered statistically significant. Results: MTT test result showed the two groups of odontogenic medium + 10 nm 1α,25 vitD3 and odontogenic medium + 150 nm 1α,25 vitD3 provided the most suitable conditions for cell viability at 72 h. Expression of both genes significantly increased in the presence of 1α,25 vitD3 (P < 0.001). Expression of both genes was significantly higher at 14 days compared with 7 days (P < 0.01). At both time points, expression of both genes was significantly higher in the presence of 150 nm 1α,25 vitD3 compared with 10 nm (P < 0.01). The accumulation of cells with odontoblastic morphology, cell interactions, and calcifications were evident. Conclusion: 1α,25 vitD3 upregulates DMP1 and DSPP and results in odontogenic differentiation of SHEDs in odontogenic medium. This upregulation increases with time and by an increase in concentration of 1α,25 vitD3.

The etiopathology of maxillary sinusitis of dental origin (MSDO) is well established, and chronic apical periodontitis is the second most common cause of all dental-induced sinusitis incidents. The literature presents no common treatment protocols for MSDO and very few studies address the impact of root canal treatment (RCT) in its management. The literature presents cases of maxillary sinusitis resolution after performing a multivisit nonsurgical endodontic treatment, yet none described complete healing of MSDO as a result of single-visit nonsurgical RCT. This paper reports a case series of maxillary sinusitis of endodontic origin (MSEO) associated with upper maxillary molars that were successfully treated with single-visit nonsurgical antiseptic RCT. In all cases, the clinical symptoms subsided within a week after endodontic treatment. Control cone-beam computed tomography (CBCT) scan showed healing of periapical bone and total resolution of maxillary sinusitis symptoms. MSDO treatment protocol should start with nonsurgical antiseptic RCT. Single-visit nonsurgical endodontic treatment can be effective in MSEO management. CBCT is a method of choice in MSEO diagnostics. Endodontists are well trained and well equipped to treat MSDO, and the cooperation between ear, nose, and throat specialists, maxillofacial surgeons, and endodontists is crucial for both: good diagnostics and treatment.

Background: Lichenoid reaction (LR) is a relatively common mucocutaneous disease with an unknown etiology. Since the cause of the LRs is unknown, many drugs have been studied to palliate the symptoms. Previous studies reported that corticosteroids are often effective in the management of several oral inflammatory diseases. The aim of the present study was to compare the effect of Melissa gel and triamcinolone 0.1% paste on clinical indices of oral LRs. Materials and Methods: In this randomized clinical trial, sixty patients with erosive oral LRs were randomly divided into two groups, and each group was treated with Melissa gel or triamcinolone acetonide 0.1% paste, three times a day, for 4 weeks. The recovery rate and severity of pain and burning sensation were assessed after 2 and 4 weeks. Finally, the obtained data were analyzed using SPSS software (version 20, IBM Corp., Armonk, NY, USA) and repeated measures ANCOVA, Mann–Whitney test, Chi-square test, paired t-test, and survival analysis.(α = 0.05). Results: The Visual Analog Scale scores for recovery rate, pain, and burning mouth sensation and objective scoring for oral lichen planus were significantly improved at 2 and 4 weeks in both the groups. However, the pain intensity decreased significantly in the Melissa group, as compared to the triamcinolone 1% group. Conclusion: In general, we showed that Melissa gel has a better effect than triamcinolone on pain intensity. Although Melissa gel is effective in reducing lesion size, triamcinolone significantly showed better results.

Background: Antimicrobial nanoparticles (NPs) have various applications in different fields of dentistry. The purpose of incorporating NPs into orthodontic adhesives is to inhibit the cariogenic bacteria and reduce decalcifications around bonded orthodontic brackets. However, they may affect the physical and mechanical properties of adhesive such as shear bond strength (SBS). This review was done to answer the question whether the incorporation of antimicrobial NPs into orthodontic adhesives changes the SBS. Materials and Methods: An electronic search was performed with keywords such as adhesives AND nanoparticles AND orthodontics AND shear strength. After screening and applying eligibility criteria, 18 relevant studies were included. Results: The pooled data suggest that except for 10 wt% of various NPs incorporation, there is no significant difference in SBS between control conventional adhesives and experimental modified ones with tested concentrations. Conclusion: The SBS of orthodontic adhesives containing up to 5% NPs is in clinical acceptable range. However, generalizing the results to in vivo situation may be problematic and further studies are required.

Background: This study aimed to assess and compare the type of dental procedures performed under general anesthesia for healthy and disabled children. Materials and Methods: This descriptive, cross-sectional study evaluated 361 dental records of children who received dental treatments under general anesthesia in the operating room of Torabinejad Research Center during 2011–2013. Patients with mental or physical disability were categorized as disabled. The age and gender of patients, number of treated teeth, duration of general anesthesia, type of tooth, and type of dental treatment such as extraction, pulp therapy, placement of stainless steel crowns, composite restoration, preventive resin restoration (PRR), fissure sealant treatment, and fluoride therapy were separately recorded for the healthy group and patients with disability. Data were analyzed using one-way ANOVA, and independent sample t-test at P < 0.05 level of significance. Results: Of 361 patients, 263 patients were healthy and 102 patients had disability. Of all disabled children, 48% had physical and 52% had mental disability. Among patients with physical disability, allergy (40%), followed by cardiovascular diseases (26%) were the most common. Mental retardation (54%) followed by cerebral palsy (10%) were the most common mental disabilities. Number of extracted teeth was significantly higher in disabled children (P = 0.006). Furthermore, disabled children received significantly lower PRR (P = 0.015), fissure sealant treatment (P = 0.003), fluoride therapy (P = 0.002), and pulp therapy (P < 0.001) compared with healthy children. Conclusion: Tooth extraction has a higher frequency in disabled children; while, attempts are made to preserve the teeth as much as possible in healthy children.

Aims: The present study aimed to evaluate the stress distribution of porous tantalum implant and titanium solid implant assisted overdenture (IAO) in mandibular bone by utilizing three-dimensional (3D) finite element (FE) analysis. Materials and Methods: In this FE study, an existing cone-beam volumetric tomography scan of a patient without any maxillofacial anomaly with an available acceptable IAO for mandible was used to attain the compartments of a completely edentulous mandible. Zimmer trabecular implants and locator attachment systems were selected as the case group (Model B), and Zimmer Screw-Vent implants and locator attachment system were chosen for the control (Model A), as overdenture attachments in the present study. The mandibular overdenture was scanned and digitized as a FE model. Two 3D FE models were designed as edentulous lower jaws, each with four implants in the anterior section of the mandible. Three forms of loads were directed to the IAO in each model: Vertical loads on the left first molar vertical molar (VM). Vertical loads on the lower incisors (VI). Inclined force buccolingually applied at left first molar (IM). Results: Under all loading conditions, the maximum strain values in peri-implant bone in Model A were less than Model B. Under VI, the greatest stress value around abutments in both models was about 2–3 times higher than the other loads. Under VM and IM loads, no significant difference was observed between models. Conclusion: Using trabecular metal implants instead of solid implants reduces strain values around both cortical and trabecular bone.

Background: Cleaning and shaping of root canals are essential steps for the success of endodontic therapy. This study compared two types of rotary files in oval-shaped root canals: XP-endo shaper (FKG, La Chaux-de- Fonds, Switzerland) and Mtwo (VDW, Germany, Munich) with regard to cleaning ability and canal preparation. Mtwo is a system of nickel–titanium files with S-shaped cross-sectional design and XP-endo shaper can change its shape according to the temperature. Materials and Methods: This in vitro study was performed on 16 pairs of freshly extracted contralateral mandibular premolars with a single oval-shaped canal that were selected and divided into two groups according to the root canal instrumentation technique: XP-endo shaper and Mtwo. Then, each root cut into three coronal, middle and apical sections and processed for histologic evaluation of canal wall planning and the presence of debris. Sections were evaluated by using AutoCAD 2017 software. Statistical analysis was used to compare between both the groups using repeated measures multivariate analysis of variance with Bonferroni correction for post hoc comparison and independent sample t-tests. The level of statistical significance was set at P < 0.05. Results: With a statistically significant difference in the middle third, untouched area and area with debris in XP-endo shaper group were smaller (respectively P = 0.013 and P = 0.011). Despite the percentage difference between groups, there was not a statistically significant difference in other sections. Conclusion: Statistically in the middle section of the oval-shaped canals, the XP-endo shaper performs better than the Mtwo rotary files.

Background: This study aimed to assess the effect of different whitening toothpastes containing activated charcoal, abrasive particles or hydrogen peroxide on the color of aged microhybrid composite. Materials and Methods: In this in vitro, experimental study, 45 composite discs (2 mm × 7 mm) were fabricated of a microhybrid composite. They underwent accelerated artificial aging for 300 h, corresponding to 1 year of clinical service. The composites were then randomly divided into five groups (n = 9). One group served as the control and underwent tooth brushing with distilled water. The remaining four groups underwent tooth brushing with Colgate Total whitening (Gt), Colgate Optic White (Go), Perfect White Black (Gp) and Bencer (Gb) toothpastes in a brushing machine The International Commission on Illumination values (L_m, a_m, b_m) were determined using a spectrophotometer. Color change (ΔE) calculated based on this formula: ΔE_m= ([ΔL_m] ² + [Δa_m] ² + [Δb_m] ²)^½. The differences were defined by ΔE₁ (after aging-baseline),ΔE₂ (after brushing-after aging) and ΔE₃ (after brushing-base line). ΔE₁ were evaluated to ensure that color mismatch had occurred (△E1 > 5.5). Difference in (L, a, b) parameters after aging and after tooth brushing in each group, color parameter changes (ΔL_2, Δa₂, Δb_2, ΔL_3, Δa₃, Δb₃) and ΔE₂ and ΔE₃ were analyzed and compared using Wilcoxon test and independent sample median test at P = 0.05 level of significance. Results: The color parameter changes, ΔE₃ and △ E₂ were not significantly different among the five groups (P > 0.05). In Gp and Gb charcoal a*, b*, and L* after tooth brushing (P < 0.05). In Colgate Optic group, the a* parameter significantly decreased while the L* parameter significantly increased (P < 0.05). Conclusion: The results showed that there is no significant difference in the color change of Spectrum composite following tooth brushing with different whitening toothpastes for two weeks. It should be noted that △ E₃ reached to <3.3 only in charcoal whitening toothpastes.

Background: It is difficult to perform dental procedures in autistic children, and parental involvement is necessary for successful hospital dental services. Therefore, in order to promote oral health in autistic children, this study was aimed to explore the knowledge, attitude, and performance of autistic children's parents with respect to hospital dentistry. Materials and Methods: This cross-sectional study was conducted with the parents of 100 autistic children aged 2–6 years selected from among the children of Isfahan autism treatment centers. A self-administered questionnaire, including parental demographic information and 22 items on the assessment of knowledge, attitude, and performance of autistic children's parents regarding hospital dental procedures under general anesthesia, was completed by 100 parents. P <0.05 was considered statistically significant. Data were analyzed by SPSS software using Chi-square test. Results: A total of 100 parents of autistic children, with an average age of 37.4 ± 6.1 years, were recruited in this study. The results showed that 56%, 50%, and 3% of parents had poor knowledge about dental hospital services, dental complications, and hospital dentistry rules, respectively. Further, 51% of parents believed that general anesthesia was dangerous to their children. In addition, 69% of children had little or no cooperation with the dentist. There was also a significant relationship between the knowledge, attitude, and performance of autistic children's parents regarding hospital dentistry and the parents' age and sex. Conclusion: This study showed that autistic children's parents had poor knowledge, attitude, and performance with respect to hospital dentistry.

Background: Dentists might face various artifacts (such as triangular-shaped radiolucencies [TSRs]) during the assessment of radiographs and should be able to differentiate them from caries to avoid unnecessary treatments. Materials and Methods: In this cross-sectional study, 109 maxillary second primary molars were evaluated in cooperative children aged 4–9 years, who had distal caries in their maxillary first primary molars. First, TSRs were recorded on periapical radiographs of each maxillary second primary molar's proximal surface. Then, after excavating distal caries in the adjacent teeth “D,” a pedodontist examined the mesial surfaces of teeth “E.” Chi-square test was used to compare the distribution of caries in different variables, and the kappa coefficient was applied to evaluate clinical and radiographic agreements. A P < 0.05 was considered statistically significant. Results: Forty-four cases were found to be carious both clinically and radiographically, and 54 cases were noncarious by both methods, while for 11 cases, the diagnosis was controversial. No statistically significant difference was found between radiographic and clinical caries detection methods in children whose periapical radiographs contained TSRs, and most of the subjects had similar diagnoses. Value of caries detection sensitivity, specificity, positive predictive value, and negative predictive value in TSRs was 88%, 92%, 90%, and 90%, respectively. Conclusion: Considering high radiographic sensitivity for caries detection in TSRs, clinicians should be more cautious about them being carious or not, and both radiographic and clinical examinations are necessary. Further, to avoid misinterpretation in radiographs, additional education is necessary for young dentists.

Ossifying fibromas (OFs) are benign, well-demarcated lesions in the craniofacial region, particularly in the jaws, with clinical, radiographic, and histopathological similarities to other lesions, which make their diagnosis challenging. Herein, we report a case of a fibro-osseous lesion in the anterior maxilla of a 13-year-old boy, consisting of an intraosseous and an extra-osseous part, which created a diagnostic dilemma.

Background: The aim of this study was to evaluate the retention of implant-supported overdentures with different attachment systems. Materials and Methods: In this in vitro study edentulous model with 2 Straumann implant in symphyseal region was used to make an overdenture with different attachment systems. (Dolder bar with 1 and 3 metal clips, Hader bar with 1 and 3 plastic clips, ball on bar with 2 and 4 plastic caps, Locator, Rhein plastic caps and Eleptical matrix). Retention values were recorded by universal testing machine with a cross speed of 50.8 mm/min in vertical, posteroanterior, and lateral direction. Repeated measure ANOVA and Duncan tests were used for the data analysis (α =0.05). Results: There was a statistically significant difference between the retention values of studied attachments in different dislodgment directions (P < 0.05). The highest and lowest retention were recorded for 4 balls on bar (56.71 N) and Rhein pink caps (27.89 N) in the vertical direction. Three metal clips (61.43 N) and Rhein pink cap (24.77 had the highest and lowest retention force in the posteroanterior direction. In the lateral direction, 4 balls on bar (62.68 N) and 1 plastic clip (32.27 N) showed the highest and lowest retention, respectively. Conclusion: If the higher retention force has been considered for implant-supported overdenture attachment selection, the clinician can use splinted bar or ball on bar superstructure.