Abstract

Robert L. Karlinsey*, Allen C. Mackey, Emily R. Walker, Bennett T. Amaechi, Ramalingam Karthikeyan, Kaveh Najibfard and Aaron M. Pfarrer

Prescription 1.1% sodium fluoride (NaF) dentifrices designed to either have fast dispersion for improved enamel fluoride uptake (that is, PreviDent® Booster 5000) or contain an innovative tricalcium phosphate system for enhanced remineralization (that is, Clinpro® 5000) were evaluated for anticaries potential in an in vitro pH cycling model. Polished bovine enamel specimens were initially softened in a white- spot-forming solution comprising 0.1 M lactic acid plus 100 kDa polyacrylic acid (PAA, pH = 5.0) for 26 h at 37°C. Specimens were then measured for baseline Vickers microhardness and stratified (N =into the following groups: Group A: Tom’s of Maine fluoride-free dentifrice (negative control); Group B: Colgate PreviDent® Booster 5000 (5000 ppm fluoride) and Group C: 3M Clinpro® 5000 (5000 ppm fluoride). The groups were then cycled for 10 days in a pH cycling model consisting of four one-minute treatment periods (diluted 1:3 with distilled water) and one four-hour acid challenge (lactic acid-PAA , pH = 5.0) per day. Between these events, specimens were immersed in artificial saliva (pH = 7.0). After 10 days of cycling, the specimens were evaluated for Vickers surface microhardness, mineral loss and lesion depth using microindentation, transverse microradiography and polarized light microscopy. For all analyses, statistical differences (t-tests, p<0.05) were found to exist among the groups, with Clinpro® 5000 conferring superior surface and subsurface remineralization potential relative to both PreviDent® Booster 5000 and Tom’s of Maine fluoridefree paste. Due to this superiority, these results suggest the combination of 5,000 ppm fluoride plus the tricalcium phosphate system may provide significant anticaries benefits relative to fluoride-only and fluoridefree dentifrices.