High resolution fluoride profiles of artificial in vitro lesions treated with fluoride dentifrices and mouthrinses during pH cycling conditions.

A pH cycling model which incorporated a severe demineralization component was used to evaluate fluoride uptake and lesion progression for each of a NaF-based dentifrice, NaF-based mouthrinse and a monofluorophosphate (MFP)-based dentifrice. Simultaneous transverse fluoride and calcium profiles across the resulting artificial lesions were obtained using a proton microprobe technique with a resolution of approximately 10 microns. Longitudinal microhardness testing and proton microprobe calcium profiles were used to determine the extent of lesion progression (delta Z) with respect to untreated controls. Under the pH cycling conditions of the present study, the NaF dentifrice and mouthwash were observed to have a considerably higher uptake of fluoride in the lesion than the MFP dentifrice. Although the mineral content profiles of the lesions differed for treatments with each of the fluoride products, the differences were not significantly different in this model.