The effectiveness of two different battery-powered toothbrushes on whitening through removal of stain

Whitening dentifrices have recently become popular, achieving a whitening benefit by surface chemical action and/or abrasion that serve to remove extrinsic stains and/or prevent extrinsic stain buildup. Some powered toothbrushes have also been demonstrated to have whitening/stain-removal efficacy when used with standard dentifrice products. The objective of this study was to evaluate the effectiveness of an experimental prototype powered toothbrush (Crest SpinBrush Pro) and a commercially available powered toothbrush (Crest SpinBrush) on dental whitening through the removal of extrinsic stain. This study was a randomized, controlled, examiner-blind, parallel-group design, which examined extrinsic stain removal over four weeks of brushing by 70 subjects. Following a three-week period of stain induction using rinses of chlorhexidine and tea, subjects were randomized to use one of the two toothbrushes. Tooth stain was scored using the Lobene stain index at baseline, and after two and four weeks of toothbrush use. Prior to statistical analysis, the stain scores were averaged on a per-subject basis. The stain reductions (baseline minus post-treatment) in average scores were calculated and analyzed using an analysis of covariance, with baseline average score as the covariate. The experimental prototype powered toothbrush (Crest SpinBrush Pro) delivered statistically significant (p < 0.001) adjusted (via analysis of covariance) mean reductions from baseline in Lobene composite stain scores of 1.90 and 2.11 after 2 weeks and 4 weeks of use, respectively. These results represent 56-62% reductions in extrinsic stain compared to baseline. The commercially available powered toothbrush (Crest SpinBrush) also delivered statistically significant (p < 0.001) adjusted (via analysis of covariance) mean reductions from baseline in Lobene composite stain scores, with magnitudes of 1.95 and 2.22 after two and four weeks of use, respectively. These results represent 60-68% reductions in extrinsic stain compared to baseline. In conclusion, both the experimental prototype powered toothbrush and the commercially available powered toothbrush were effective in removing extrinsic tooth stain.