Association between Enamel Abrasion and Surface Roughness of Dental Ceramics
Introduction: Feldspathic porcelains and zirconia crowns are the most applied dental ceramic materials. Teeth wear against these ceramics has turned into a major concern. Primary surface roughness of these ceramics can have a significant impact on enamel abrasion. This study aimed to detect an association between enamel abrasion and surface roughness of dental ceramics. Materials Methods: In this laboratorial study, polished zirconia samples, polished feldspathic porcelains, and polished and glazed feldspathic porcelains were prepared (N=11) In addition, human natural premolar teeth were provided as antagonist. Afterwards, mounted tooth samples were photographed by a stereo microscope in a fixed position and the distance from the cusp tip to the reference point was measured. Surface roughness of all samples was evaluated before the test using a profilometer device. Following that, ceramic samples were tested against dental samples. Moreover, 11 tooth samples (control group) were tested against another 11 tooth samples in chewing simulator device with 120000 masticatory cycles (equal to six months of chewing) Afterwards, tooth samples were photographed again and differences between the measurements were recorded. Data analysis was performed in SPSS version 20 using the kruskal Wallis test and scatter diagram graphs, and P value of less than 0.05 was considered statistically significant. Results: In this study, mean and standard deviation of surface roughness rate in polished porcelain, polished and glazed porcelain, polished zirconia ceramics and control group were 1.48+ 0.083, 1.20+ 0.126, 0.535+ 0.086 and 0.039+ 0.006 micrometers, respectively. According to the results, a statistically significant difference was observed between the level of surface roughness in the study groups (P<0.001) Among the ceramics, the highest levels of abrasion and surface roughness were observed in the polished porcelain group, whereas the lowest levels were allocated to the polished zirconia group. Conclusion: According to the results of this study, higher level of surface roughness of ceramics increased tooth abrasion.