The Effect of Different Solutions on Optical Behavior of Polished and Glazed Zirconia-Reinforced Lithium Silicate Ceramics

This study sought to assess the effect of glazing and polishing surface treatments on the optical behavior of zirconia-reinforced lithium silicate ceramics thermocycled in different solutions. Computer-aided design/computer-aided manufacturing ceramics (VITA Suprinity) were cut into samples (n=104) measuring 1.5x14x10 mm according to the manufacturer’s instructions. Also, the samples were then randomly divided into four groups for immersion in artificial saliva, tea, orange juice and cola. A spectrophotometer was used to assess the color change and changes in L* coordinate against a white and a black background. The translucency parameter and contrast ratio were also calculated. The ∆E and L* values were analyzed using two-way ANOVA test. Student’s t-test was applied to analyze TP and CR. The interaction effect of the type of solution and type of surface treatment on color change against a white (P=0.008) and black (P 0.001) background was statistically significant. Immersion of ceramic samples in orange juice and cola caused significant changes in TP and CR in the polishing and glazing groups (P 0.05). Immersion in orange juice causes clinically perceivable color change in glazed ZLS ceramics. Immersion in cola decreases the translucency of both polished and glazed ZLS ceramics.