Fluoride Release from Glass Ionomer Cements and Compomers in vitro

Objective: to measure the fluoride released from a group of glass ionomer cements and compomers, in vitro using the fluoride ion specific electrode over a period of four months. materials and methods: the daily fluoride release of three conventional glass-ionomer cements (ketac-fil, fuji ix gp and fuji vii), two light cured glass-ionomer cements (fuji ii lc and vitremer) and two compomers (dyract ap and f-2000) was measured over a period of four months. ten cylindrical specimens (surface area= 1.996 cm²) were made of each of the materials, 10 mm in diameter and 1.5mm in thickness using the same mould. measurements of the fluoride release in 5 ml of deionized water (25°c) were performed at intervals of one day, weekly for the rest of the first month, and monthly for the remaining three months. results: a burst effect of fluoride release was observed initially with at least a ten-fold decrease occuring for all the materials by the end of the first week. compomers were found to release significantly less fluoride than the glass-ionomer cements during the first four months. the (mean ± sd) daily fluoride release for the materials at four months was: fuji vii (0.31± 0.06 ppmf), ketac-fil (0.31± 0.08 ppmf), vitremer (0.27± 0.05 ppmf), fuji ii (0.12± 0.03 ppmf), fujiix (0.09± 0.05 ppmf), f2000 (0.07± 0.05 ppmf) and dyract (0.06± 0.01 ppmf). conclusions: the most fluoride was released by fuji vii and ketac-fil. dyract released the least fluoride of all the materials.