Effects of Ceramic Shade, Ceramic Thickness, and Surface Treatment on the Color Match of High‐Translucency Monolithic Multilayer Zirconia Restorations

<b>Purpose:</b> The purpose of this in vitro study was to evaluate the effects of ceramic shade, ceramic thickness, and surface treatment on the color match of high-translucency monolithic multilayer zirconia restorations. <b>Materials and Methods:</b> Seventy-two high-translucency monolithic multilayer zirconia disk specimens with different shades (A2, A3, B2, and B3) and different thicknesses (1, 1.5, and 2 mm) were fabricated, polished, and glazed. CIELab values were measured with a spectrophotometer in the incisal, middle, and cervical regions before and after glazing. ∆<i>E</i> ₀₀ color differences were calculated between polished and glazed specimens (Δ<i>E</i> ₁), between polished specimens and their analogous Vita classical shade tabs as targets (Δ<i>E</i> ₂), and between glazed specimens and the targets (Δ<i>E</i> ₃). The ∆<i>E</i> ₀₀ values were compared with a 50:50% acceptability threshold (∆<i>E</i> ₀₀ = 1.8) to assess color matches. Repeated measures ANOVA, Bonferroni, and 1-sample <i>t</i>-tests were used for data analysis (<i>α</i> = 0.05). <b>Results:</b> Mean ∆<i>E</i> ₀₀ values ranged between 1.11 and 2.74 for Δ<i>E</i> ₁, between 2.69 and 6.78 for Δ<i>E</i> ₂, and between 1.47 and 5.59 for Δ<i>E</i> ₃. The overall mean values were 1.82, 4.66, and 3.63 for Δ<i>E</i> ₁, Δ<i>E</i> ₂, and Δ<i>E</i> ₃, respectively. Ceramic shade, ceramic thickness, and surface treatment significantly affected the CIELab values (<i>p</i> < 0.05). All mean ∆<i>E</i> ₂ and ∆<i>E</i> ₃ values were greater than the threshold (<i>p</i> < 0.05) except for the mean ∆<i>E</i> ₃ for the 1.5- and 2-mm-thick, A3 shade, glazed zirconia in the cervical region (<i>p</i> > 0.05). <b>Conclusions:</b> The color match of high-translucency monolithic multilayer zirconia restorations depends on ceramic shade. Additionally, increased ceramic thicknesses (≥1.5 mm) and glazing can improve the color match of these restorations.