In vitro influence of different topical fluoride applications on remineralization of enamel observed by the quantitative light-induced fluorescence method

Abstract

Abstract We did an in vitro study using quantitative light-induced fluorescence (QLF) to evaluate enamel remineralization caused by application of topical fluoride. Artificial incipient carious lesions were formed in bovine dental enamel by immersion for 24, 48, 72 or 96 hours in a demineralizing solution. Each demineralization group was then divided into four subgroups based on the type of fluoride application: the controls (no application), fluoride dentifrice, APF-gel, and fluoride dentifrice with APF-gel. The remineralization recovery rate of the carious lesions was calculated on days 3, 6, 9, 12, 15, 21 and 28 using data obtained with QLF. The recovery rate of the controls and the fluoride dentifrice group were approximately 90% for each demineralization group at 28 days. The recovery rate for the two APF treated groups was about 85% for the group demineralized for 24 hours. However, the subgroup treated with APF-gel that had been demineralized for 96-hours had only a 40% recovery rate. We concluded from this in vitro study that APF-gel treatment inhibited remineralization in highly demineralized carious lesions.