Comparative efficacy and tolerability of two direct-to-consumer tooth whitening systems

To compare the clinical response of two self-directed vital bleaching systems under market use conditions.

A randomized, parallel-group clinical trial was conducted. A total of 20 healthy adults were randomized to either a 6.0% hydrogen peroxide strip-based bleaching system or a combination system involving a 10% carbamide peroxide gel in a stock tray along with an anticavity whitening dentifrice and after-bleaching whitening mouthrinse. Only the maxillary arch was bleached over a 14-day period. Subjects were evaluated at 3, 8 and 15 days. Efficacy was measured objectively using digital image analysis to derive individual color parameters (L*a*b*) and overall color change (deltaE*).

After 14 days, the adjusted mean reduction in yellow (Ab*) was -2.23 +/- 0.157 for the whitening strips compared to -0.97 +/- 0.188 for the combination system. This represented a highly statistically significant (P< 0.0001), two-fold superior reduction in yellowness for the whitening strip group compared to the marketed control. Similar results were seen for other color parameters, with the whitening strip group exhibiting two-fold color improvement relative to the tray/dentifrice/rinse combination. With respect to tolerability, tooth sensitivity and oral irritation were the most common findings. Considering event duration and severity, median bleaching tolerability severity-days scores were 0.07 and 0.58 for the strip and combination systems respectively, with these treatments differing statistically (P= 0.04 1) favoring the whitening strips.