Comparative Evaluation of Color Stability of Monochromatic and Nanofilled Resin Composites After Exposure to Two Different Beverages using a Spectrophotometer—An in Vitro Study

Background & Aim: The cosmetic efficacy of dental restorations is significantly influenced by color stability. Although resin composites are preferred for their optical and mechanical attributes, staining from drinks continues to pose a clinical issue. This research assessed the color stability of monochromatic and nanofilled resin composites following exposure to staining drinks.

Materials and Methods: Sixty composite discs (8 mm in diameter, 2 mm in thickness) were produced from monochromatic and nanofilled resins, subjected to light curing, and subsequently polished. Specimens were randomly allocated to six groups and submerged in coffee, tea, or distilled water (control). Baseline and post-immersion color measurements were obtained using a spectrophotometer in accordance with the CIELAB color standard. The color change was determined using the ΔE formula, which relies on alterations in L*, a*, and b* coordinates. Data were examined using two-way ANOVA and subsequent post-hoc testing (p < 0.05).

Results: Both materials exhibited discoloration upon exposure to beverages, with coffee inducing the most pronounced staining across all test groups. The nanofilled composite had markedly reduced ΔE values, indicating enhanced color stability relative to the monochromatic composite (p < 0.05).

Conclusion: The exposure to beverages markedly modifies the hue of composite restorations. Nanofilled composites exhibit superior resistance to discoloration compared to monochromatic variants, therefore affirming that material composition and filler technique determine long-term aesthetic durability.