Abstract
Fluoride is considered to be an important caries-preventive agent as it decreases the solubility of tooth minerals. The aim of the present study was to investigate the amount of fluoride ion released, over a 9 day period, from four restorative glass ionomer cements (GIC). Elemental analysis, for O, F, Na, Mg, Al, Si, P, S, Ca, Sr, Zn, and Zr, was performed on three conventional glass ionomers [ChemFil ROCK (Dentsply), Fuji IX (GC), and Riva self-cure (SDI)] and one resin-modified glass ionomer, Ketac Nano (3M ESPE) using Energy Dispersive Spectrometry (EDS). A digital caliper was used to measure the length and diameter of each sample. The fluoride release, in mu g/cm(2), from the samples in deionized water was measured for 9 days using a fluoride ion selective electrode and analyzed using the SPSS. The release of fluoride on day 1 from Fuji IX was significantly higher (6.19 +/- 1.04 mu g/cm(2)) than that from Ketac Nano (3.88 +/- 0.13 mu g/cm(2)), Riva self-cure (3.19 +/- 0.66 mu g/cm(2)), and ChemFil ROCK (1.68 +/- 0.08 mu g/cm(2)). The value found for Fuji IX was comparable to that found in various other experimental settings. The difference in fluoride release on day 1 between Ketac Nano and Riva self-cure was not significant. The fluoride release from day 5 to day 9 stabilized at a lower level for all the ionomers and no statistically significant difference in the level of release was present between them during that period. I concluded that there is a wide range in the release of the fluoride ion among restorative glass ionomer cements with the highest level of release on day 1 being observed in Fuji IX, followed by Ketac Nano, Riva self-cure, and ChemFil ROCK.