Influence of depth and translucency on the color matching of single-shade resin composites: An in vitro study

Abstract:

To evaluate whether the depth and translucency of the restoration influence the color matching of single-color resin composites, cylindrical cavities (2-and-4 mm depths) were prepared in acrylic teeth 62 shade (n=10). Restorations were performed with single-shade resin composites (OC: Omnichroma, Tokuyama; VU: Vittra APS Unique, FGM) and a control multi-shade (EO: Estelite Omega, Tokuyama). The color matching was measured in instrumental analysis (CIEDE2000 color difference formula (ΔE₀₀)) and visual analysis (0 to 4 scale). The translucency of discs (2-and-4mm thickness) was obtained by color difference (ΔE₀₀) between black and white background. Two-way ANOVA followed by the post-hoc Tukey's test was used to evaluate instrumental analysis, and Kruskal-Wallis followed by the post-hoc Tukey's test to evaluate color matching with a significance level of 5%. Restoration depths affected the ΔE₀₀ values of OC and VU (p<0.05) (higher ΔE₀₀ values for 4-mm depth and higher for OC and VU (p< 0.05)). The restoration depths did not influence the color matching in the visual analysis. VU and OC showed higher translucency scores than EO. At 2 mm, OC showed higher translucency values and there was no difference between OC and VU at 4 mm (p <0.05). The color matching of OC and VU was influenced by depth (instrumental analysis). While the OC had a similar color matching to EO at both depths, VU had the best color matching in both depths in the visual analysis. Single-shade materials had greater translucency than EO at different depths, and the translucency decreased with increasing depth.

Key Words:
blending effect; chameleon effect; structural color; monochromatic resin composite