Shade Modulation Ability of Direct vs. Direct-Indirect Prepless Composite Veneers

Assess the shade modulation ability of direct-indirect prepless composite veneer using distinct composite resins and cement shades by instrumental and visual assessments.

A total of 270 samples of direct and direct-indirect composite veneers were fabricated using three composite resins (3M Filtek Supreme Ultra A1B, Tokuyama Omnichroma, Transcend Universal) over a 3D designed mold in 10 × 10 mm cuboid shape with three depth cuts on the surface (0.3, 0.5, and 0.7 mm) to stimulate the veneer preparation and bonded using Ivoclar Variolink Esthetic LC neutral and light cement shades over a standard C4 shade substrate. Measurements were gathered through instrumental assessment by spectrophotometry and through visual assessment by four dental professionals. Color differences (ΔE ₀₀) were calculated according to the CIEDE2000 formula. Statistical analysis was conducted using three-way ANOVA followed by the Tukey test.

The ΔE values were influenced by the technique (p < 0.001), thickness (p < 0.001), and type of composite resin (p < 0.001). Cement shades were not statistically significant in the final shade of the direct-indirect technique (p = 0.168). There was no mismatch in the visual assessment between the direct-indirect samples compared to the direct samples.

There is a difference in the final shade between the direct and direct-indirect techniques in the instrumental but not in the visual evaluation. The two cement shades used did not influence the final shade of the composite veneers.