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Dental Caries and Staining after Twenty-eight Months of Rinsing with Stannous Fluoride or Sodium Fluoride

The aim of this study was to compare the effects of daily mouthrinsing with aqueous solutions of 0.05% NaF or 0.1% SnF2 on dental caries and tooth staining. The study population consisted of 437 children, aged from 12 to 15 years at baseline, residing in a non-fluoridated community. By stratified random sampling, the subjects were divided into two groups, one group rinsing daily under supervision for 28 months with the NaF solution and the other with the SnF2 solution. The SnF2 group exhibited four to five times as much extrinsic stain as did the NaF group, although the stains were quite mild and not explicitly distinguishable between groups. There were no statistically significant differences between the two groups in terms of total DMFS. However, the increment of pit and fissure caries was 0.9 surfaces fewer for the SnF2 group (p = 0.04), while the increment of smooth surface caries was 0.6 surfaces fewer for the NaF group (p = 0.04). These data suggest that there may be a difference in mechanism of action between SnF2 and NaF rinses.