Meta-analysis of the Clinical Effectiveness and Tolerability of Direct-to-Consumer Vital Bleaching Products

Objective: The introduction of strips, trays and paint-on products has contributed to change and extraordinary growth in self-directed tooth whitening. This research was conducted to systematically evaluate the clinical effectiveness and tolerability of the most popular direct-to-consumer systems. Methods: A meta-analysis was conducted using an inclusive dataset from 5 randomized clinical trials having common entrance criteria and methods. Each study evaluated a direct-to-consumer, peroxide-based tooth whitening system under labeled use conditions, with 6.0% hydrogen peroxide strips as a reference control. Effectiveness was measured objectively as L*a*b* color change using digital image analysis, and tolerability was assessed by subject report. Comparative efficacy was evaluated using a mixed model that adjusted for study, age and baseline color. Results: The pooled sample included 160 subjects (18-60 years of age) who used direct-to-consumer products at concentrations from 0.75 to 6.0% hydrogen peroxide. Compared to the strip control, the self-directed tray/paint-on products exhibited only 4-36% of the adjusted mean Db*, and 2-57% of the adjusted DL*. Adjusting for multiple comparisons, there were no significant (p > 0.47) differences in Db* between any of the tray/paint-on products. Outcomes were generally consistent across other color parameters (DL*, Da*, DE*, DW*). In all instances, the strip group exhibited highly significant (p < 0.001) and superior whitening to the other self-directed products. While no subjects dropped “for cause”, there were directional or significant differences in tolerability usually favoring the strips. Conclusion: While there were few differences between the individual tray/paint-on products, 6.0% hydrogen peroxide strips exhibited superior and meaningful whitening relative to the other popular direct-to-consumer products.