Yağmur Lena SEZİCİ, Aslı AŞIK, Genta AGANI SABAH
Meandros Medical and Dental Journal - 2026;27(2):273-281
Objective: This study aimed to compare the effects of whitening mouthwashes containing different active agents on the color stability of coffee-stained clear aligners. Materials and Methods: Sixty-five clear aligner specimens (Invisalign, Align Technology, San Jose, CA, USA) were randomly allocated into five groups (n=13) according to the mouthwash: SPLAT(R) Professional Bioactive White Plus, Listerine Advanced White, Colgate Optic White, Marvis Whitening Mint, and Biomed Superwhite. Baseline color (t0) was measured using a spectrophotometer. All specimens were immersed in a coffee solution for 7 days to induce standardized discoloration (t1), followed by immersion in the assigned mouthwash for 28 minutes to simulate two weeks of clinical use (t2). L*, a*, b* coordinates and color differences (DeltaE00) were analyzed using repeated measures ANOVA and one-way ANOVA, with post hoc comparisons performed using Tukey's test (alpha=0.05). Results: Coffee immersion significantly decreased L* and increased b* across all groups (p<0.001). Following mouthwash immersion, a significant increase in L* and a reduction in b* values were observed in all groups (p<0.001). SPLAT demonstrated the highest final lightness and the lowest final yellowness values (p < 0.05). All DeltaE00 values exceeded the clinical acceptability threshold of 1.8. Biomed Superwhite and SPLAT showed significantly lower residual color differences (DeltaEt0 -t2) compared with Colgate Optic White (p<0.005). No significant differences were found among the groups regarding the net whitening effect (DeltaEt1 -t2) (p>0.05). Conclusion: Whitening mouthwashes produced partial but clinically insufficient color improvement in coffee-stained aligners; none restored baseline optical properties. Oxidative or enzymatic formulations yielded better residual color recovery than stain-inhibiting systems.
