Objective: Two randomized, six-week, double-blind, parallel group, clinical trials were independently conducted to compare the extrinsic stain removal efficacy of a novel whitening therapeutic dentifrice containing 0.454% stannous fluoride and sodium hexametaphosphate in a formulation with high cleaning silica, relative to a positive control whitening dentifrice.
Methodology: Generally healthy adults, 56 for study 1 and 60 for study 2, with visible extrinsic tooth stain were enrolled in the studies. At the baseline visit, stain was assessed on the facial surfaces of the eight central and lateral incisors using the modified Lobene Stain Index. Oral soft and hard tissue examinations were also conducted. In each study, subjects were randomized to either the stannous fluoride + sodium hexametaphosphate toothpaste (Crest Pro-Health) or the positive control toothpaste (Colgate Total Plus Whitening) to use twice per day for six weeks. Stain and safety were reassessed at weeks three and six.
Results: Fifty-two and 58 subjects completed studies 1 and 2, respectively. In each study, there were no statistically significant differences in Lobene composite stain scores between the two treatment groups across all three visits. Both groups showed statistically significant reductions in Lobene composite stain scores at week three (p < 0.0001) and week six (p < 0.0001) relative to baseline. The percent of Lobene composite scores with a greater than 0.5 unit reduction from baseline at week six was 86% for study 1 and 97% for study 2 for the stannous fluoride + sodium hexametaphosphate dentifrice group.
Conclusion: Collectively, these two stain removal clinical trials demonstrate the statistically significant extrinsic stain removal efficacy for the stannous fluoride + sodium hexametaphosphate dentifrice relative to baseline. There were no statistically significant differences between the stannous fluoride + sodium hexametaphosphate dentifrice and positive control treatment group.