Clinical trial comparing 2 hydrogen peroxide tooth whitening systems: strips vs pre-rinse

A randomized, examiner-blind, parallel-group, clinical trial evaluated the efficacy and safety of a whitening, prebrushing mouthrinse compared with a whitening strip control. Both the pre-rinse (2% hydrogen peroxide) and whitening strips (10% hydrogen peroxide) were used twice daily with normal toothbrushing over a 1-week period. Clinical response (efficacy and safety) was evaluated on day 3 and day 8. Tooth color (L*a*b*) was measured objectively from standardized digital images of the maxillary anterior teeth, while safety was assessed from the clinical examination and participant report. All 28 randomized participants completed the study. Relative to baseline, the whitening strip group experienced significant (P <.001) color improvement at day 3, continuing (P <.001) through day 8. The pre-rinse group did not show any significant (P >.12) change at day 3, and had a significant (P=.033) increase in yellowness at day 8. Adjusted mean +/- standard error treatment differences were -1.75 +/- 0.198 for deltab*, 1.11 +/- 0.212 for deltaL*, and -0.54 +/- 0.131 for deltaa*, with the strip group exhibiting significantly (P <.001) greater whitening at day 8. Both products were well tolerated, with no participants discontinuing treatment early as the result of an adverse event. In head-to-head testing, 7-day use of the 10% hydrogen peroxide whitening strips resulted in significant tooth color improvement relative to a barrier-free 2% hydrogen peroxide pre-brushing mouthrinse.