Comparative tooth whitening and extrinsic tooth stain removal efficacy of two tooth whitening dentifrices: six-week clinical trial.

OBJECTIVE

The objective of this six-week, examiner-blind clinical study was to assess the tooth whitening and extrinsic tooth stain removal efficacy of a new dentifrice delivering 1.0% hydrogen peroxide, 0.243% sodium fluoride, and sodium tripolyphosphate in a high-cleaning silica base (Test Dentifrice), relative to that of commercially available hexametaphosphate-containing whitening dentifrice (Positive Control Dentifrice).

METHODOLOGY

Following a baseline oral soft tissue examination and scoring of extrinsic tooth stain and tooth shade, qualifying adult male and female subjects from the Harrisburg, Pennsylvania area were randomized into either the Test or Positive Control Dentifrice group. The two groups were balanced for gender, extrinsic tooth stain, and tooth shade scores. All subjects were provided their assigned dentifrice and a soft-bristled adult toothbrush for home use. Subjects were instructed to brush their teeth for two minutes twice daily (morning and evening) using only the dentifrice provided, and to refrain from using any other oral hygiene products for the entire six weeks of the study. There were no restrictions regarding diet or smoking habits during the course of the study. Oral soft tissue, extrinsic tooth stain, and tooth shade assessments for each subject were repeated after two and six weeks of product use. All statistical tests were two sided and employed a level of significance of alpha = 0.05.

RESULTS

Fifty-six (56) subjects complied with the protocol and completed the entire study. Compared to baseline at both the two- and six-week examinations, the Test Dentifrice group had statistically significant reductions in extrinsic tooth stain area and intensity, and statistically significant mean shade rank reductions, with a six-week reduction of 4.81. In contrast, at six weeks, the Positive Control dentifrice had a statistically significant increase in tooth stain area, a non-significant increase in tooth stain intensity, and a statistically significant mean 1.40 shade rank score reduction. At both the two- and six-week examinations, the Test Dentifrice group had statistically significantly lighter tooth shades and statistically significantly lower levels of extrinsic tooth stain area and intensity than the Positive Control Dentifrice group.

CONCLUSION

A new whitening dentifrice delivering 1.0% hydrogen peroxide, 0.243% sodium fluoride, and sodium tripolyphosphate in a high-cleaning silica base has significant efficacy in tooth whitening and extrinsic stain removal, and provides a statistically significantly greater level of efficacy for both tooth whitening and extrinsic tooth stain removal than the commercially available Positive Control Dentifrice.