Effect of gingival shade on the color matching of universal composite resins in Class V restorations: a photometric analysis
摘要
The aim of this in vitro study was to evaluate the color matching of single-shade and group-shade universal composite resins used in Class V restorations on A3-shade teeth in the presence of different simulated gingival shades using a photometric analysis method.
Materials and MethodsClass V cavities prepared on 45 extracted human anterior teeth were restored using one group-shade universal composite resin (Neo Spectra ST (NEO)) and two single-shade universal composite resins (Zenchroma (ZC) and Omnichroma (OC)) (n = 15). Standardized digital photographs were obtained under D65 illumination using cross-polarization filters. A commercial gingival shade guide providing three different gingival shades (light, medium, and dark) was used, along with a no-gingiva condition (control). The photographs were calibrated using a gray reference card in Lightroom software. Color differences (ΔE₀₀) were calculated using the CIEDE2000 formula. Data were analyzed using robust mixed ANOVA, with the level of significance set at p < 0.05.
ResultsComposite resin type had a statistically significant effect on ΔE₀₀ values (p < 0.01). NEO (2.15 ± 0.067) exhibited lower ΔE₀₀ values compared with ZC and OC. Gingival shade alone did not significantly affect ΔE₀₀ values (p = 0.232); however, the interaction between composite resin type and gingival shade was statistically significant (p < 0.01).
ConclusionAlthough the group-shade composite resin demonstrated better color matching than the single-shade composite resins, all ΔE₀₀ values observed in the study exceeded the clinically acceptable threshold (ΔE₀₀ > 1.8).
Clinical RelevanceWhen evaluating the color matching of universal composite resins in Class V restorations, the influence of gingival shade may vary depending on the composite resin used.