Can the Application of Fluoride lontophoresis Improve Remineralisation of Early Caries Lesions?

Purpose: To determine the optimal electric current intensity of fluoride iontophoresis (FI) for remineralisation of early caries lesions in vitro. Materials and Methods: Sixty specimens were made from bovine incisors and immersed in a demineralising gel for 96 h. Specimens were divided into control (conventional fluoride application) and experimental (FI) groups. All of the specimens were covered with fluoride for 4 min every day. Different electric current intensities (100, 200, 300 and 400 mu A) were applied in the Fl groups using the Fl device. The concentration of KOH-soluble fluoride was determined to evaluate the amount of CaF2 formed on the tooth surface. The reduction in lesion depth was measured by polarised light microscopy. Results: The concentration of KOH-soluble fluoride was the highest in the specimens of the 300 mu A Fl group. However, there was no significant difference in the reduction of lesion depth between the experimental groups and the control group. Conclusion: Variations in the electric current intensity influenced the amount of CaF2 formed on the enamel surface, with the greatest amount found for 300 mu A.