Abstract
The possible correlation between the expansion of fillings made from fluoride-releasing glass polyalkenoate cement and water sorption of the materials was examined. Resin-modified glass ionomer materials had larger amounts of water sorption than conventional glass ionomer cements(acid-base type). And resin-modified glass ionomer materials had larger amounts of expansion by water sorption than conventional glass ionomer cements after immersion in distilled water kept at 37℃. There were positive correlations between the amounts of water sorption and expansion of each material. A semicircular profile was observed on the expanded surface of the resin-modified glass ionomers filled in the pre-treated bovine cavities, while the specimens filled in Teflon cavities generally revealed a trapezoidal shape. The absorption of water influence the surface profiles of glass ionomers filled in cavities, particularly for the resin-modified glass ionomers. The adhesion of glass ionomers to the cavity walls may influence the direction of expansion by water sorption.
