Effect of Ceramic Thickness and Cement Type on the Color Match of High-Translucency Monolithic Zirconia Restorations.

Abstract

To find proper ceramic thickness-cement combinations for color matching of high-translucency monolithic zirconia restorations. A total of 300 A2-shade high-translucency zirconia disk specimens of six different thicknesses (0.7, 0.9, 1.1, 1.4, 1.6, and 1.8 mm) were cemented to A3.5-shade composite resin backgrounds with five different cements: Temp-Bond, Zinc Phosphate, RelyX Unicem 2, PANAVIA SA Cement Plus, and GC Gold Label 1. Color measurements were conducted before and after cementation to determine the specimens' CIE L*a*b* values. ΔE00 values were calculated for specimens to assess color differences between before cementation and after cementation (ΔE1), between the A2 VITA classical shade (target) and specimens before cementation (ΔE2), and between the target and specimens after cementation (ΔE3). The ΔE3 values were compared with an acceptability threshold (ΔE00 = 1.8) to evaluate color matches. Data were analyzed using two-way analysis of variance, Bonferroni, and one-sample t tests (P < .05). Mean ΔE3 values ranged between 1.0 and 3.4. Ceramic thickness, cement type, and their interaction affected the ΔE3 (P < .001). Temp-Bond with ceramic thickness of ≥ 1.1 mm and Zinc Phosphate with ceramic thickness of ≥ 0.9 showed color matches, but RelyX, PANAVIA SA, and GC did not show color matches with any tested ceramic thickness. Opaque cements with sufficient ceramic thicknesses created color matches for high-translucency monolithic zirconia restorations on A3.5-shade backgrounds.