The Effect of pH on Fluoride Release of Glass Ionomer Based Restorative Materials

Abstract

Three Glass-ionomer based restorative materials (Conventional Glass-ionomer cement, resin-modified Glass-ionomer cement and Compomer) were used. The number of the specimens for the fluoride measurement and surface hardness test was 156 specimens. The specimens for each material were divided into four equal groups: the first group was dry stored, the second group was stored in solution pH7, the third group was stored in solution pH5 and the last group was stored in solution pH3. All the specimens were stored in an incubator at 37°C for seven days. Fluoride release after seven days was measured with fluoride ion selective electrode. The amount of fluoride released from the three materials were significantly higher in acidic solutions than in neutral solutions. The Compomer released the highest amount of fluoride into the three storage solutions, while the least fluoride release was from the resin-modified glass-ionomer.