Color stability of bulk-fill and universal composite restorations with dissimilar dentin replacement materials.

Objective To determine color changes in bulk-fill composite and universal composite restorations with dissimilar dentin replacement materials in extracted teeth after staining in red wine. Materials and Methods Cylindrical, 4 mm deep, class I cavities were prepared in 140 human molars. Bottom 2 mm was restored with Biodentine (Septodont), everX posterior (GC) or experimental HAP inserts. Each dentin replacement material was covered with a 2-mm layer of a universal composite Filtek Z250 or Z550 (3M ESPE) or Gradia Posterior (GC). Groups combining top composite layer and the underlying dentin replacement were designated as "composite_dentin replacement." Filtek Bulk Fill (3M ESPE) and Tetric EvoCeram Bulk Fill (Ivoclar Vivadent) were placed as a single 4-mm layer. Color measurements were performed using Vita Easyshade 4.0 (Vita Zahnfabrik) initially and after 48-hours storage in red wine at 37 degrees C. Results Color differences (Delta E-oo) ranged between 2.1 +/- 0.7 (Z250_HAP) and 7.8 +/- 1.1 (Z550_everX). EverX resulted in higher Delta E-oo of the overlying composite than HAP (P < .001) and Biodentine (P = .006). Generally, Delta E-oo was affected more by decreasing lightness (Delta L ') than changes in chroma (Delta C '). Conclusions EverX resulted in higher Delta E-oo of the restoration than Biodentine and experimental HAP after staining in red wine. No significant differences in Delta E-oo may be expected in different composites with the same underlying dentin replacement material. The same was generally true for bulk-fill and universal composites. Clinical Significance Similar extent of color changes may be expected in bulk-fill and universal composites. Highly translucent everX might exhibit greater color differences irrespective of the capping composite than non-translucent materials. Clinicians have a wider choice of composite materials to cover a particular dentin replacement material, for example, everX or Biodentine, as similar color differences may be expected in various overlying composite brands.