Placebo Controlled Trial of Daily Hydrogen Peroxide Whitening Strips

Objective: A randomized placebo-controlled trial was conducted to evaluate clinical safety and efficacy of a daily 6% hydrogen peroxide whitening strip. Methods: Balancing for age and tooth color, 55 adults were randomized and treated with 6% hydrogen peroxide thin gel whitening strips with pyrophosphate or placebo strips. In this 12-week, double-blind clinical trial, strips were applied unsupervised to the maxillary teeth once daily for 5 minutes. At 3-week intervals, efficacy was measured objectively as L*a*b* color change from digital images, and safety was assessed from examination and subject report. Results: Mean (SD) age was 33.7 (11.2) years, 53% were female, and 18% used tobacco daily. Groups did not differ (p >0.42) on baseline demographic parameters or tooth color. Beginning at Week 3, only the hydrogen peroxide group exhibited significant (p<0.001) L*a*b* color change. Color improvement continued through Week 12. At that end-of-treatment visit, the adjusted Δb* (yellowness) means ± standard errors were –1.6 ± 0.17 and –0.1 ± 0.18 for the 6% and placebo groups, respectively. Adjusted ΔL* (lightness) means ± standard errors were 1.5 ± 0.13 in the 6% strip group versus 0.0 ± 0.15 in the control. Groups differed significantly (p < 0.001) on Δb* and ΔL* at all post-baseline time points. There was only 1 adverse event over the 12-week study, minor tooth sensitivity reported by one subject in the placebo group. No subject discontinued treatment early due to an adverse event. Conclusion: This placebo-controlled, double blind clinical trial demonstrated that 5-minute daily use of a 6% hydrogen peroxide strip yielded significant tooth whitening without meaningful side effects.