A randomized clinical trial comparing a novel 5.3% hydrogen peroxide whitening strip to 10%, 15%, and 20% carbamide...

A randomized and controlled, parallel-group clinical trial compared the whitening benefits of a novel 5.3% hydrogen peroxide bleaching strip to 10%, 15%, and 20% carbamide peroxide tray-based bleaching systems. A total of 36 healthy adults were randomized to a 14-day regimen in which both arches were whitened for 1 hour per day in the whitening-strip group or 2 hours per day in the tray groups. Efficacy was measured objectively using digital images of the anterior teeth at baseline and after 14 days of treatment. Overall tooth color (L*a*b*) was derived from individual pixel values, and then mean levels of delta b*, delta L*, and composite color (delta E*) were compared using analysis of covariance. After 14 days of treatment, all groups experienced a greater than 1-unit mean improvement in delta b*, delta L*, and delta E* relative to baseline. For the primary study variable, reduction of yellow (delta b*) outcomes after 14 hours of using the experimental strip were comparable to those observed with the 10% tray group after 28 hours of use. These two treatment groups did not differ statistically with respect to any of the color measurements used in this study. For the tray groups, there was a reasonable dose relationship for the primary end point, delta b*, with the 15% and 20% tray groups averaging 17% and 68% improvements in yellow, respectively, over the 10% group. Except for the 20% carbamide peroxide system, where sensitivity was relatively common, all test products were well tolerated. In this first comparative evaluation vs marketed controls, use of the whitening strips twice daily for 14 days yielded a highly significant improvement in tooth color vs baseline.