The influence of varying fluoride concentrations on in vitro remineralisation of artificial dentinal lesions with differing lesion morphologies

Objective: The influence of low-level fluoride (F) concentrations and lesion characteristics on the remineralisation of sub-surface root caries was investigated in vitro. Design: Experimentally produced dentinal carious lesions were exposed to artificial saliva in the presence of 0.00 ppm, 0.48 ppm, 2.49 ppm or 4.91 ppm F (as NaF) for 5 days. Calcium, phosphate and fluoride ion uptake was quantified by chemical assay. Baseline changes in the mineral content and distribution of the lesions were assessed by transverse microradiography (TMR). Results: The uptake of calcium and phosphate was significantly increased (p < 0.05) by fluoride, even at low concentrations. The action of fluoride was influenced by the mineral content and distribution of the lesions at baseline, however, with the location and degree of mineral deposition being strongly related to the mineral content of the lesions surface layer. Conclusions: The process of remineralisation of root dentine is multifactorial. The morphology of lesions at baseline significantly affected the location and quantity of mineral deposition. (C) 2007 Elsevier Ltd. All rights reserved.