Clinical Efficacy and Safety of Two Marketed Whitening Treatments

Objective: This clinical study compared efficacy and safety of two marketed whitening treatments. Methods: 26 subjects were randomized and received one of two whitening regimens: Rembrandt® 2 Hour Whitening kit (2-hour kit) with four applications to be completed in one day or Crest® Whitestrips® Premium containing 10% hydrogen peroxide and worn 30 minutes twice a day for 7 days (7-day strips). Each treatment followed the manufacturers written instructions. Tolerability was assessed from subject interviews and oral examination, and efficacy was measured objectively from CIELAB digital measurements. Whitening response was compared at Day 2, Day 5, Day 8 and at the end-of-treatment (Day 2 for the 2-hour kit and Day 8 for the 7-day Strip) using the analysis of covariance method. Results: The study population was healthy adults averaging 41.3 years of age. At the end-of-treatment, use of 2-hour kit resulted in adjusted means of -0.39 for Δb* and 0.68 for ΔL*, while the use of 7-day strips resulted in adjusted means of -2.14 for Δb* and 1.58 for ΔL*. Groups differed significantly (p ≤ 0.006) on Δb* and ΔL* favoring the 7-day strip group. In addition, the 7-day strip group demonstrated significantly greater improvement of b* and L* (p ≤ 0.05) relative to the 2-hour kit at Days 5 and 8. Both treatments were generally well-tolerated, and there were no adverse event dropouts in the study. Conclusion: Use of a marketed 10% hydrogen peroxide, 7-day whitening strip resulted in a significantly greater tooth whitening response relative to that of a marketed 2-hour whitening kit.