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Placebo-controlled clinical trial evaluating a 10% hydrogen peroxide whitening strip
Robert W Gerlach1, Paul A Sagel, Matthew L Barker
1The Procter & Gamble Company, Health Care Research Center, Mason, OH, USA. gerlach.rw@pg.com
Objective:
A placebo-controlled clinical trial was conducted to evaluate the effectiveness and safety of a 10% hydrogen peroxide strip-based whitening system in subjects with tooth discoloration and no previous history of tooth whitening.
Methodology:
Informed consent was obtained, and 39 healthy adults were randomly assigned to either 10% hydrogen peroxide whitening strips (Crest Whitestrips Premium) or placebo strips with no peroxide. Strips were used unsupervised twice daily for 30 minutes over a seven-day period. At day four and day eight, tooth color (L*a*b*) was measured on the maxillary anterior teeth from standard digital images, and safety was assessed from examinations and subject reports.
Results:
After three treatment days, the 10% hydrogen peroxide strip group had significant (p < 0.0001) color improvement from baseline, with means (SD) for deltab* and deltaL* of -1.57 (0.472) and 1.72 (0.619), respectively. Continued strip use from day four to day eight resulted in significant (p < 0.002) incremental improvement in both yellowness and lightness. By the end of treatment (day eight), the adjusted mean (SE) color change between groups was -2.20 (0.275) for deltab* and 2.24 (0.254) for deltaL*, a highly significant (p < 0.0001) color improvement for the 10% hydrogen peroxide group relative to placebo, of similar absolute magnitude for deltab* and deltaL*. Treatment with the 10% hydrogen peroxide strips was well-tolerated, with tooth sensitivity and oral irritation representing the most common findings.
Conclusion:
In this double-blind, placebo-controlled clinical trial, statistically significant tooth whitening was evident after three days' treatment with 10% hydrogen peroxide whitening strips, and color improved with continued usage over seven days.
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