Evaluating the effects of remineralizing agents on initial carious lesions.

Background: Initial carious lesions are reversible, and fluoride-containing reagents effectively promote enamel remineralization in these initial lesions. Numerous remineralizing agents are available, some containing fluoride and others containing alternatives because of fluoride toxicity concerns. The objective of this study was to investigate the effects of the following remineralizing agents: fluoride varnish (5% NaF, Duraphat Materials and Methods: Forty human maxillary premolar teeth were randomized into 4 experimental groups: distilled water, fluoride varnish, CPP-ACP, and CPP-ACPF. All 40 teeth were cut in half mesiodistally. A Vickers microhardness test was performed on the buccal half of each tooth; the lingual half was examined with a spectrophotometer for colour dimension. An Atomic Force Microscope was used to evaluate roughness. During the experiments, microhardness, colour, and roughness were examined 3 times: 1) before treatment; 2) after demineralization; and 3) after remineralization. At each stage, a scanning electron microscope was used to examine surface features and enable energy dispersive X-ray chemical composition analysis. Results: Demineralization carried out in preparation for testing of the agents caused enamel hardness to decrease significantly. Enamel roughness increased, although not significantly. After remineralization, each of the 3 remineralizing agents had significantly increased both hardness and lightness (L*), compared to the demineralized enamel. Each agent decreased enamel roughness, but the roughness change was not significant. Conclusion: Comparing the 3 remineralizing agents, there were no significant differences between the agents in effectiveness.