At-Home and In-Office Bleaching Protocols on the Color Match of Restorations Made With Single-Shade Composites

Abstract

Objective

This study evaluated the color match of restorations made with single-shade composites following two protocols of tooth bleaching.

Materials and Methods

Cavities in the cervical third of bovine crowns were restored using single-shade composites (Omnichroma or Vittra Unique) or a multi-shade composite restoration strategy (Filtek Z350 XT). The color of both the restoration and the middle third of the unrestored tooth were recorded. The Whiteness Index for Dentistry (WID) and color differences (ΔE ₀₀) between the two areas were calculated. Specimens underwent bleaching using in-office or at-home protocols, and color evaluations were repeated at 24 h, 7 days, and 14 days post-bleaching. Data were analyzed using MANOVA and repeated measures ANOVA.

Results

Bleaching protocols did not significantly affect WID or ΔE ₀₀ values. The highest WID values were observed for Vittra Unique, and the lowest for Filtek Z350 XT. Tooth bleaching did not affect ΔE ₀₀ values for restorations made with the multi-shade strategy, but it resulted in a reduction for those made with the single-shade strategy, regardless of the composite brand.

Conclusion

Tooth bleaching protocols differentially affected the color match of restorations made using single-shade composites compared to multi-shade restorations.

Clinical Relevance

Tooth bleaching protocols have a limited effect on the color of composites but can influence the color match between the restoration and the surrounding enamel. Specifically, color mismatches tend to decrease for lighter materials, such as single-shade composites, after tooth bleaching, improving the overall esthetic integration of the restoration with the natural tooth structure.