A METHOD FOR DETERMINING THE DISTRIBUTION OF FLUORIDE, CALCIUM AND PHOSPHORUS IN HUMAN DENTAL PLAQUE AND THE EFFECT OF A SINGLE IN-VIVO FLUORIDE RINSE

A new sampling method, capable of sampling plaque from its surface to its interior for quantitative studies, was modified to meet some of th e requirements for the determination of the fluoride and mineral (Ca a nd P) profiles within dental plaque formed in vivo. Plaque samples wer e repeatedly collected from the same individual, using special devices , before a single fluoride rinse (900 parts/10(6) fluoride) and 10 min and 24 hr after rinse. The method allowed examination of fluoride, ca lcium and phosphorus distribution along the entire thickness of plaque . Fluoride content significantly increased throughout the sample 10 mi n after rinsing, indicating the fluoride had rapidly penetrated into t he plaque. Although the elevated fluoride concentrations diminished al most to baseline with 24 hr, a high cor relation was found between flu oride and minerals in each plaque fraction. It is concluded that this technique will be useful for evaluating the fluoride and mineral behav iour in the saliva/plaque and plaque/enamel interfaces, and the anti c aries efficacy of fluoride applications. (C) 1997 Elsevier Science Ltd .