Effect of Surface Finishing Methods and Corrosion on Surface Elemental Composition and Roughness of Dental Ceramics
Aims: The aim of this study was to compare the effect of surface finishing methods and chemical corrosion on surface elemental composition and roughness of ceramic materials.
Material and Methods: 20 ceramic disks were fabricated from A1 shade of Empress, Zirkonzahn, Noritake Cerabien ZR, Finesse, Vita VM7 and divided into 2 groups of autoglaze and polishing(n=10). The surface roughness (Ra) and surface elemental analyses were evaluated before and after in vitro corrosion (pH 4.5–pH 7–pH 9 in water at 37°C ± 2°C for 18 hours and at pH 2.4 in 4% acetic acid at 80°C ± 2°C for 18 hours). The data were statistically analyzed by Univariate Analysis of Variance and Bonferroni Test. Multiple comparisons of Ra values between autoglaze and polishing groups for each brand of ceramic were computed by T-Test.
Results: Analyses showed that the surface was dominated by Na, Al, Si. Glazed ceramics showed less ion change than polished ceramics at high intensity corrosion. No significant difference was found between Ra values of ceramics for both surface finishing methods, except Empress, a glass ceramic.
Conclusion: The surface compositions of ceramics were found to differ according to type and brand of ceramic. Surface elemental composition did not make a difference on surface roughness or surface finishing technique. On the other hand surface elemental composition changes after chemical corrosion giving a sign of dissolution of ceramics.