Effects of different polishing and glazing systems on the physical properties of ceramics

PURPOSE: The purpose of this study was to assess the surface roughness, color stability, and contact angle of lithium disilicate glass-ceramic (LD) and zirconia-reinforced lithium silicate (ZLS) ceramics following surface finishing and to compare these values using both manufacturer-specific polishing and glazing procedures and alternative methods designed for other types of ceramics. MATERIALS AND METHODS: LD and ZLS ceramics were used to fabricate 80 samples, which were allocated into eight groups (n = 10) according to manufacturer-specific polishing (VITA Suprinity Polishing Set Clinical and OptraGloss Ceramic Kit) and glazing protocols (VITA Akzent Plus and Ivocolor Glaze) and their interchanged applications. Measurements of surface roughness, contact angle, and color stability were made following the polishing and glazing processes. The results were evaluated using parametric statistical analysis. RESULTS: Glazing produced a statistically significant change with the LD ceramic, whereas polishing did not. In the ZLS group, there was a significant difference between the glazing methods, but there was no statistically significant difference between the polishing techniques. In both ceramics, the contact angle values of the glazed samples were greater than those of the polished samples. CONCLUSION: Surface finishing procedures significantly affected both the color change of the ZLS ceramic and the surface roughness of the LD ceramics. The contact angle values of the glazed samples in both ceramics were approximately two to five times greater than those of the polished samples. It may be advisable for clinicians to use nonmanufacturer-specific techniques for polishing ceramic materials, especially in areas that do not affect their appearance, such as the back of the mouth.