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Extrinsic stain removal efficacy of a dual-phase dentifrice
1College of Stomatology, Fourth Military Medical University, Xi'an, China.
Purpose:
To evaluate the extrinsic stain removal benefit of a sodium hexametaphosphate containing dual-phase dentifrice (Crest Vivid White) relative to a marketed negative control (Colgate Cavity Protection).
Methods:
This was a parallel groups, examiner-blind, randomized and controlled clinical trial. A total of 200 healthy adults with natural stain on their anterior teeth were enrolled into the study. Following baseline examination, subjects were randomly assigned to one of the two treatment groups based on baseline Lobene composite scores, smoking status (yes/no), tea/coffee consumption (yes/no), and gender. Subjects brushed twice daily, at least 1 minute every time over 6 weeks. Clinical examinations including extrinsic stain evaluation and oral soft tissue examination were conducted at BL, Weeks 3 and 6. Extrinsic stain removal was evaluated on the anterior teeth by a dental examiner using Lobene stain index.
Results:
Of the 200 subjects who were randomized to treatment, 195 were available for the 3-week examination and 193 subjects completed the study. The dual-phase dentifrice exhibited a statistically significant (P< 0.01) reduction in Lobene stain composite scores when compared to the negative control dentifrice at Week 6. Adjusted mean Lobene composite reduction for the dual-phase dentifrice group (0.32) was twice as big as the negative control group (0.16). Change in Lobene stain extent (area) contributed primarily to the overall composite score reduction. All test products were well tolerated over the 6-week treatment period.
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