Evaluation of Shade Integration of a Novel Universal-Shade Flowable Bulk-Filling Resin Composite

Background: This study aimed to evaluate the color-matching and light transmission properties of a newly developed aesthetic flowable resin composite, OCFB-001.

Methods: Rubber molds containing cylindrical cavities were filled with Estelite Sigma Quick, and 40 resin composite (CR) molds with simulated Class I cavities were prepared in shades A1, A2, A3, and A4, resulting in a total of 160 samples. Following bonding procedures, four different flowable resin composites (n = 10) were introduced into the cavities. The color difference (ΔE₀₀) was calculated using two methods. A two-way analysis of variance was performed, and the interaction was significant, so a post hoc analysis was performed for each shade using Bonferroni's correction. The morphology of the filler in each material was observed via scanning electron microscopy (SEM).

Results: In the A1 shade, OCFB-001 demonstrated color differences comparable to those of other materials. However, in the A2, A3, and A4 shades, OCFB-001 exhibited significantly lower color differences (ΔE₀₀) than the other materials, with a more consistent distribution. SEM analysis revealed that the OCFB-001 structure resembled that of Estelite Bulk Fill Flowable.

Conclusions: OCFB-001 showed excellent shade matching in the A2, A3, and A4 ranges and good matching in the A1 shade, on par with existing universal-shade flowable bulk-fill resin composites.