Effect of sintering temperature on translucency parameter of zirconia blocks
Fariborz Vafaei1, Armaghan Shahbazi2, Amirarsalan Hooshyarfard3, Amir Hosein Najafi4, Maziar Ebrahimi4, Maryam Farhadian5
1 Dental Implants Research Center, Department of Prosthodontics, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran
2 Department of Prosthodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
3 Department of Periodontics, Dental Materials Research Center, Tehran Medical Sciences, Islamic Azad University, Faculty of Dentistry, Shahed University, Tehran, Iran
4 Dentist, Private Practice, Hamadan University of Medical Sciences, Hamadan, Iran
5 Department of Biostatistics, School of Public Health and Research Center for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran
Dr. Armaghan Shahbazi
Department of Prosthodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran
Source of Support: None, Conflict of Interest: None
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.