Effect of Universal Shade of Resin Cement on the Final Color of Ceramic Restorations

Abstract

Objective: To investigate the effect of neutral (N) and universal (Un) shade resin cement on the final color of thin ceramic restorations. Materials and Methods: Forty specimens (8x8x0.8 mm(3)) were sliced from five leucite reinforced glass-ceramic blocks. Another 40 rectangular composite specimens were prepared from a resin die material (8x8x4 mm(3); IPS Natural Die Material, A1 and A 3,5 IvoclarVivadent) simulating prepared teeth and divided into two cement colors. (N and Un) After baseline color measurements, each slice was cemented to a composite resin specimen, and measurements were obtained with a spectrophotometer on a white background in daylight by a single experienced investigator. The difference between the baseline and final color measurements was calculated in accordance with the CIEDE2000 color measurement formula. The CIEDE2000 perceptibility and acceptability thresholds were set to 0.8 and 1.8. The data were statistically analysed with Shapiro-Wilk and Mann-Whitney U test. Results: No significant difference was observed between. 00 value in the N (1.18 +/- 0.40) and Un (1.26 +/- 0.52) groups for the light background. The mean differences between the N (0.74 +/- 0.31) and Un (0.88 +/- 0.55) groups were insignificant for the dark background (p>0.05). Conclusion: The Un shade cement used in this study may mask the dark tooth structure when using 0.8 mm-thickness ceramic restorations. However, the results may not be clinically satisfying. The Un shade resin cement used in this study provided an improvement in color although it was insufficient to mask the underlying dark background completely. Using Un shade resin cement is a challenge under 0.8 mm-thickness ceramic restorations of dark-colored teeth. If preferred, the ceramic thickness should be increased.