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Abstract
The purpose of this study was to evaluate and compare (in vitro) the fluoride and calcium ions released from conventional glass ionomer and recent resin composite restorative materials at different pHs conditions and different time intervals. A total of 100 samples disc of the two restorative materials were used in this study. The samples were assigned in two equal groups, fifty discs each, one for conventional glass ionomer and the other for the composite resin. Within each group the samples were randomly divided into five main subgroups according to adjusted pHs. Each of these subgroups was evaluated for measuring fluoride and calcium ions released after six different time intervals.
Results obtained for the effect of pH condition on ions released from both materials and Duncans test showed that there is a significant difference (p ≤0.05) in ions released among the materials at all the test intervals.
In fact in every considered pH condition, conventional glass ionomer released a greater amount of ions than recent resin composite restorative material. Both materials released a greater amount of ions at pH 3 than at pH 4, pH 5.5, pH 7.2 and H2O. Both materials are affected by the acidic environment and are greatly damaged by acid solutions.