Effect of cement type on the color attributes of a zirconia ceramic

PURPOSE. This in vitro study evaluated the effects of four different cements on the color attributes of a zirconia ceramic. MATERIALS AND METHODS. 40 zirconia ceramic disk specimens (0.5 mm thickness, 10 mm diameter, 0.1 mm cement space) were fabricated by a computer-aided design and computer-aided manufacturing system. The specimens were divided into 4 groups of 10 specimens and cemented to composite substrates using four different cements including: Glass Ionomer, Panavia F2.0, Zinc Phosphate, and TempBond. The $L^*$, $a^*$, and $b^*$ color attributes of the specimens were measured before and after cementation by a spectrophotometer. Additionally, ${\Delta}E$ values were measured to determine color changes for the groups and then compared with the perceptional threshold of ${\Delta}E=3.3$. Repeated Measures ANOVA, Tukey Post Hoc, Bonferroni, One-way ANOVA, and One-sample t-test tests were used to analyze the data. All tests were carried out at the 0.05 level of significance. RESULTS. Statistically significant differences were detected in the ${\Delta}E$ values for Zinc Phosphate (P<.0001) and TempBond (P<.0001) groups. However, there were no statistically significant differences in this respect for Glass Ionomer (P=.99) and Panavia F2.0 (P=1) groups. The means and standard deviations of the ${\Delta}E$ values for Glass Ionomer, Panavia F2.0, Zinc Phosphate, and Tempbond groups were $2.11{\pm}0.66$, $0.94{\pm}0.39$, $5.77{\pm}0.83$, and $7.50{\pm}1.16$ Unit, respectively. CONCLUSION. Within the limitations of this study, it was concluded that Zinc Phosphate and Tempbond cements affected the color attributes of the tested zirconia ceramic beyond the perceptional threshold. However, Glass Ionomer and Panavia F2.0 cements created acceptable color changes.