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Fluoride Uptake from in situ Brushing with a SnF2 and a NaF Dentifrice

Fluoride uptake into decalcified human enamel was determined from in situ brushing with a 0.40% SnF2-calcium pyrophosphate abrasive dentifrice, a 0.243% NaF-silica abrasive dentifrice, and a non-fluoride-silica abrasive placebo dentifrice. Dentifrice treatments were compared using a randomized block test design with 11 panelists, wearing specially fabricated partial dentures that were able to hold two 3-mm-diameter enamel discs in proximal positions. The enamel discs were analyzed for fluoride after two wk of regular use of the test dentifrices. The mean fluoride contents after use of the test dentifrices were 16.0, 8.4, and 4.6 μg/cm2 for the 0.243% NaF, the 0.40% SnF2, and the placebo dentifrice, respectively. The differences in the means were statistically significant. These uptake results correlate well with the reported clinical efficacies of these dentifrices.