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A clinical investigation of the tooth whitening efficacy of a new hydrogen peroxide-containing dentifrice.

OBJECTIVE
The objective of this four-week, double-blind clinical study was to assess the tooth whitening 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 a control dentifrice containing 0.243% sodium fluoride in a silica base (Control Dentifrice).


METHODOLOGY
Following a baseline oral soft tissue examination and tooth shade assessment using the Vita Shade Guide, qualifying adult male and female subjects from the New Delhi, India area were randomized into either the Test or Control Dentifrice group. The two groups were balanced for baseline mean Vita Shade Guide rank scores. All subjects were provided with 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 four weeks of the study. There were no restrictions regarding diet or smoking habits during the course of the study. Oral soft tissue and tooth shade evaluations for each subject were repeated after two and four weeks of product use.


RESULTS
Forty-four (44) subjects complied with the protocol and completed the entire study. At the two- and four-week examinations, the Test Dentifrice group had statistically significant mean shade rank score reductions of 4.04 and 5.17, respectively, compared to baseline (p < 0.05), while the Control Dentifrice had respective reductions of 0.41 and 0.53, which were also statistically significant. The mean shade rank reductions in the Test group compared to those in the Control group at two and four weeks were 3.63 and 4.64, respectively, and were statistically significant (p < 0.05).


CONCLUSION
A new whitening dentifrice delivering 1.0% hydrogen peroxide, 0.243% sodium fluoride and sodium tripolyphosphate has significant tooth whitening effectiveness, producing a mean shade rank score reduction from baseline of 5.17 after four weeks' use.