Resin Cement: Correspondence with Try-In Paste and Influence on the Immediate Final Color of Veneers

To assess the correspondence of shades between try-in pastes and resin cements and their influence on the final color of veneers.

Bovine teeth (n = 140) were prepared and divided into 2 groups (a or b) according to ceramic veneer thickness (0.35 or 0.70 mm). Seventy teeth (n = 70) were distributed in 7 groups (groups 1 to 7a and groups 1 to 7b; n = 10). Try-in pastes and their corresponding resin cements were used according to the value: groups 1a and 1b (value -3); groups 2a and 2b (-2); groups 3a and 3b (-1); groups 4a and 4b (0); groups 5a and 5b (+1); groups 6a and 6b (+2); groups 7a and 7b (+3). Color measurements were performed with spectrophotometer, and the coordinates L^* , a^* , and b^* were obtained. The final color change (ΔE) was calculated from these coordinates: ΔE0 (trial - substrate), ΔE1 (cementation - substrate), and ΔE2 (cementation - trial). The data were analyzed using the Kolmogorov-Smirnov test, the Wilcoxon test, or t-test for paired samples and repeated-measures ANOVA, post hoc Bonferroni, or the Friedman test (p < 0.05).

The results indicated no statistically significant difference between the groups comparing ΔE0 and ΔE1 for 0.35 mm thickness laminate veneers, except for groups 2a and 5a. For 0.70 mm thickness laminate veneers, no statistically significant differences were observed between the groups comparing ΔE0 and ΔE1. ΔE2 values for 0.35 mm and 0.70 mm thickness laminate veneers ranged from 1.77 ± 0.81 to 4.99 ± 3.80 and from 1.01 ± 0.73 to 4.66 ± 2.96, respectively.

Try-in pastes correspond with their respective resin cements for most colors investigated. The color of the resin cement may influence the final color of laminate veneers. Thickness of the ceramic was the most relevant variable for color change.