Effect of different polishing systems on surface roughness and color stability of lithium disilicate ceramics

Objective: This study aimed to investigate the effect of two polishing systems on the surface roughness and color stability of lithium disilicate ceramic. Materials and Methods: Forty disc-shaped lithium disilicate samples were constructed and cemented into a cavity prepared onto the labial surface of freshly extracted bovine teeth; The samples were divided into four groups (10 samples per group); C: Control, SS: Scaling only, SE: Scaling followed by polishing using Eve Diapro lithium disilicate polishers, SD: Scaling followed by polishing using Diatech ShapeGuard ceramic polishing plus kit. The surface roughness was measured before scaling, after scaling and finally after the polishing procedure. The color parameters were measured before and after the staining procedures using VITA Easyshade Advance 4.0 according to the CIE L*a*b* color order system. Results: Both polishing systems significantly decreased the surface roughness of the disilicate ceramic and was accompanied by a significant decrease in the color change. However, the color change in the polished group was significantly higher than that of the control glazed group. Conclusion: The surface roughness and color stability of lithium disilicate ceramics can be enhanced by recent polishing systems, however, it shows different topography than the glazed ceramic surface.