Clinical response of two brush-applied peroxide whitening systems

A randomized, examiner-blind parallel design study was conducted to evaluate the clinical efficacy and tolerability of two brush-applied, peroxide-based tooth whiteners.

A total of 38 subjects were randomized to Colgate Simply White, an 18% carbamide peroxide paint-on liquid in an applicator bottle, or Crest Night Effects, a 19% sodium percarbonate system in unit dose sachets that dries to form an adherent film. Treatment was for 14 days. The 18% carbamide peroxide gel was applied twice daily, while the 19% sodium percarbonate film was applied for overnight use. Subjects were evaluated at baseline, and again after 7 and 14 days of treatment using digital images to assess tooth color, and oral examinations to establish safety. Whitening efficacy was determined by evaluating the reduction in tooth yellowness (delta b*), increase in tooth brightness (delta L*), reduction in tooth redness (delta a*) and overall tooth color change relative to pure white (delta W*).

After 14 days, the mean change in yellowness (delta b*) was -1.43 +/- 0.20 for the 19% sodium percarbonate film, and -0.44 +/- 0.06 for the 18% carbamide peroxide gel. Mean change in brightness (delta L*) was 1.13 +/- 0.13 and 0.55 +/- 0.13 in the film and gel groups, respectively. Between-group comparisons showed highly significant (p < or = 0.003) whitening for the 19% sodium percarbonate film compared to the 18% carbamide peroxide gel for all 14-day color measurements (delta b*, delta L*, delta a* or delta W). Both products were well-tolerated, with no subjects discontinuing treatment early due to a causal adverse event.

In a direct clinical comparison of two brush-applied products over 14 days, Crest Night Effects provided significant and meaningful improvement in tooth color, representing more than double the whitening measured for the Colgate Simply White.