Assessment of Surface Roughness and Color Change Among Metal Ceramic and Zirconia Systems: An <i>In Vitro</i> Study

Color change after repeated firings and the effect of bleaching gel on the surface roughness of different ceramic types. Using two metal ceramics and two zirconia systems, twenty disc-shaped ceramic specimens were prepared. Repeated firings were carried out, and the L.a.b. values and color differences (E) were recorded, surface roughness readings were recorded at intervals of one day, two days, one week, two weeks, three weeks, and four weeks. To evaluate the effect of bleaching samples were submerged in 15% carbamide peroxide gel. The firings number and veneering porcelain type changed the L.a.b. values with a significant relationship with the veneering porcelain type and surface roughness. Mean surface roughness and color change was assessed using analysis of variance (ANOVA). Repetition of firings has caused acceptable color changes. The IPS InLine POM and IPS e-max Zirpress had the fewest color alterations. Surface roughness was unaffected by 15% carbamide peroxide gel.