Abstract
The effects of NaHCO 3-based dental powder containing NaF and sodium saccharin on dental caries and Streptococcus mutans recoveries in rats were studied. Weanling specific-pathogen-free Osborne-Mendel (SPFOM) rats were inoculated with S. mutans NCTC-10449S. Four infected groups were topically treated with either demineralized water (DW), a dental powder suspended such that there was 1 part solid per 2 parts DW, 0.073% NaF, or a combination of 0.073% NaF and 0.5% Na-saccharin (Nas). NaF-supplemented DW (at 10 ppm F-) was provided to a 5th group of infected rats as a positive treatment control, but this group was otherwise untreated. A sixth but uninfected group was topically treated with DW. All topical treatments were given once for 1 min daily per rat, for 5 days per week. Animals' teeth were swabbed for recovery of 10449S and total recoverable flora. Recoveries of 10449S were lower from powder-treated rats than from DW-treated rats. This difference approached but did not reach statistical significance. Total caries scores were 51% lower for the dental powder, 36% lower for the topical NaF, 34% lower for the combined NaF-Nas, and 54% lower for the NaF-supplemented drinking water group, all p < 0. 001. While all of the treatments inhibited smooth-surface caries, the dental powder effects, like those for the combined NaF-Nas, and NaF drinking water, were evident in fissure tooth surfaces as well. Both the 10 ppm F- drinking water and the dental powder significantly reduced fissure caries scores below the level elicited by the indigenous mutans-free flora in the DW-treated uninfected rats; however, these reductions were not significantly different from one another. Thus, the 10 ppm F- drinking water and the dental powder equally inhibited not only the S. mutans-attributable component of caries but probably also the component of caries attributable to the indigenous oral flora.