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

Purpose: To compare the clinical response of two self-directed vital bleach ing systems under market use conditions. Materials and Methods: A randomize d, parallel-group clinical trial was conducted. A total of 20 healthy adult s 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-bleachin g 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 paramet ers (L*a*b*) and overall color change (DeltaE*). Results: After 14 days, th e adjusted mean reduction in yellow (Deltab*) was -2.23 +/- 0.157 for the w hitening strips compared to -0.97 +/- 0.188 for the combination system. Thi s represented a highly statistically significant (P < 0.0001), two-fold sup erior reduction in yellowness for the whitening strip group compared to the marketed control. Similar results were seen for other color parameters, wi th the whitening strip group exhibiting twofold color improvement relative to the tray/dentifrice/rinse combination. With respect to tolerability, too th sensitivity and oral irritation were the most common findings. Consideri ng event duration and severity, median bleaching tolerability severity-days scores were 0.07 and 0.58 for the strip and combination systems respective ly, with these treatments differing statistically (P= 0.041) favoring the w hitening strips.