Reversal of incipient and radiographic caries through the use of sodium and stannous fluoride dentifrices in a clinical trial

Experimental evidence has clearly demonstrated that the early stages of les ion formation (enamel demineralization) are reversible following exposure t o saliva and/or fluoride. Clinical evidence for remineralization has also b een reported extensively in the literature. However, the literature is lack ing with respect to data from well-controlled clinical studies regarding th e quantitative contribution of remineralization to arrestment and reversal of caries. Retrospective analysis of an existing clinical trial database pr ovided an opportunity to examine the incidence of clinical lesion reversals in a placebo-controlled, double-blinded caries clinical study. The clinica l study examined three treatment groups: 1) 0.243% sodium fluoride/silica d entifrice, 2) 0.4% stannous fluoride/calcium pyrophosphate (positive contro l) dentifrice and 3) non-fluoridated placebo/calcium pyrophosphate (negativ e control) dentifrice. Clinical measures in this study included both radiog raphic and visual-tactile assessments of caries. Examination of all subject s revealed a statistically greater frequency for caries reversals in the so dium fluoride group as compared to the placebo group at Year 3, for both to tal and radiographic caries, In contrast, while caries reversals in the sta nnous fluoride group occurred with greater frequency than in the placebo gr oup at Year 3, for both total and radiographic caries, the differences were not statistically significant. When only subjects who were ''at risk" for potential reversals (i.e., those with a mini mum of one carious lesion at b aseline) were examined, a statistically greater frequency in caries reversa ls was observed in both the sodium fluoride (total, incipient, and radiogra phic caries) and stannous fluoride (total and radiographic caries) groups a s compared to the placebo group at Year 3. Collectively, these data confirm the ability of both 0.243% sodium fluoride/silica and 0.4% stannous fluori de/calcium pyrophosphate dentifrices to clinically reverse caries. The resu lts suggest that sodium fluoride may deliver a greater frequency of caries reversals than stannous fluoride, although these treatments were not found to be significantly different.