Effect of effervescent multivitamin solutions on the color stability of contemporary resin composites: an in vitro study

Objective: Given the limited evidence on the effect of effervescent multivitamin solutions on the color stability of contemporary resin composites, this study aimed to evaluate and compare their impact under simulated daily use conditions. Materials and Methods: Five resin composites (Charisma Smart, Filtek One Bulk Fill, Omnichroma, Ruby Comp Nano, Ruby Flow) were tested using 200 disk-shaped specimens divided into a distilled water control group and three experimental groups: Sambucol Plus (SMB), Supradyn Effervescent Tablet (SPR), and Youplus Vitamin C, Zinc, Propolis (YPL) effervescent tablets. Each tablet was dissolved in 200 mL distilled water; specimens were immersed twice daily for 2 min over 28 days. Color measurements (CIELAB, ΔE00, Whiteness Index) were taken at baseline, 14 and 28 days using a spectrophotometer. Data were analyzed using repeated-measures analysis of variance (ANOVA); Welch ANOVA and Games–Howell post-hoc tests were used where appropriate, with the significance level set at p < 0.05. Results: Resin composite and immersion solution had significant effects on color change (p < 0.001), while time interval was also significant (p = 0.009). After 28 days, the highest discoloration was observed in Filtek One Bulk Fill immersed in Youplus (ΔE₀₀ = 9.93 ± 0.73), followed by Omnichroma immersed in Supradyn (ΔE₀₀ = 5.63 ± 0.83). Several groups exceeded the clinical acceptability threshold (ΔE₀₀ = 1.8), particularly Filtek One Bulk Fill and Omnichroma exposed to Youplus and Supradyn. Significant time × composite, time × solution, and time × composite × solution interactions were detected (all p < 0.001). The Whiteness Index also showed significant changes over time, particularly in the Youplus- and Supradyn-exposed groups. Conclusion: Within the limitations of this in vitro study, multivitamin effervescent tablets adversely affected the color stability of some resin composites, particularly Filtek One Bulk Fill and Omnichroma. Further clinically relevant and in vivo studies are needed to determine the significance of these findings under oral conditions.