Caries-preventive effects of sodium and amine fluoride dentifrices

Purpose: To determine the comparative effects of sodium (NaF) and amine flu oride dentifrices, as well as the effect of different silica abrasives used in NaF dentifrices, on caries formation in rats. Materials and Methods: Ha rlan Sprague Dawley mixed sex, weanling, littermate rats were fed a carioge nic diet and inoculated with S. sobrinus strain 6715 to induce caries forma tion. The dentifrices evaluated contained 0.31% NaF with precipitated silic a I as the abrasive system; 0.31% NaF with sodium bicarbonate and hydrated silica; placebo; amine fluoride (0.14%) containing silica (Elmex); 0.31% Na F with precipitated silica II (Sensodyne F); and 0.31% NaF with hydrated si lica. Dentifrice slurries were administered 7 days per week for 3 weeks at which time the animals were euthanized and the hemijaws removed, coded and stained with a murexide solution. The recovery of S. sobrinus after the 3-w eek study clearly showed that all of the six groups were infected with S. s obrinus. The Keyes scoring method was then used to assess the caries format ion within the sir; groups. Results: Caries scores showed that all five exp erimental fluoride dentifrices were equally efficacious statistically in re ducing caries formation when compared to the placebo with reductions rangin g from 26 to 43%.