Effect of Fluoride Varnish and Dentifrices and Its Combination on Deciduous Enamel Demineralization: An In vitro Study

INTRODUCTION: Dental caries remains the most important dental health problem in developing countries. Application of varnish on tooth surfaces is shown to promote the uptake of firmly bound fluoride by enamel, which is considered important. Along with the incorporation of fluoride into the crystalline lattice, there is formation of calcium fluoride compounds on enamel. METHODOLOGY: Seventy deciduous canines were covered with nail polish. A window measuring 4 mm × 4 mm was left on their buccal surface, These were randomly assigned to seven groups (n = 6): S: sound enamel not subjected to any regimen or treatment; N: negative control, subjected to the pH-cycling regimen without any treatment; D1 and D2: subjected to the pH-cycling regimen and treated two times daily with 1100 and 500 ppm F dentifrice, respectively; VF: fluoride varnish (subjected to F-varnish before and in the middle of the pH-cycling regimen); and VF + D1 and VF + D2. After a period of 10 days, sectioning of teeth was done, and enamel demineralization was measured. RESULTS: The combination of dentifrice and varnish (groups VF + D1 and VF + D2) significantly reduced demineralization compared with the N group at all distances evaluated (P < 0.05), but the combination did not differ from the dentifrice groups at most distances from the surface (P > 0.05). CONCLUSION: The results of this study suggest that the combination of F-varnish with dentifrices containing 500 or 1100 ppm F is not more effective in reducing demineralization in primary teeth than the isolated effect of dentifrice containing 1100 ppm.