Inhibition of Enamel Demineralization by Repeated Treatments with Sodium and Stannous Fluoride Solutions

Abstract

Six freshly extracted teeth were collected, from each tooth 6 sections were prepared, and all sections mounted between glass slides using the technique of Manly et al (J.D.R. 40:891, 1961). The sections were placed in a 0.5 [image] lactate buffer, pH 5.0, with outer enamel exposed. The treatment solutions used were NaF (.027%), SnF2 (.05%) and distilled water, applied for 3-5 minutes, either once or twice daily. Kodachrome transparencies of each section were made at 72 hour intervals through a polarizing microscope. The rate of decalcification was determined in microns from measurements of the decalcification front on the image of the projected slide. No difference in the rate of penetration was observed between sections treated once or twice daily with water. All of the sections treated with fluoride solutions showed less decalcification. Sections treated once a day with stannous fluoride solutions had a rate identical with those sreated twice a day with sodium fluoride solution. Sections treated twice a day with stannous fluoride solution experienced the least amount of decalcification, amounting to 58% of control at 264 hours.