Abstract
The purpose of this study was to evaluate the water uptakes and solubilities of 28 kinds of various dental filling composite resins by the method of ISO(TC106, WG1/TG9).Furthermore, the solubilities in )organic solvents[ethanol:H2O(7:3), tetrahydrofuran: H2O(9:1)]were examined.
The following results were obtained.
1)It was found that the solubility of dental filling composite resin was generally related to its water uptake (i.e.the greater the value of water uptake, the greater the value of solubility). And the inorganic filler composite resins showed less water uptakes and solubilities than the organic filler composite resins.
2)In this study, the water uptakes and solubilities of dental filling composite resins were not affected by the surface property, namely polished or not, except in the case of lightcured type composite resins.
3)When dental filling composite resins were extracted by 600 ml of water using Soxhlet's method at 85℃, for 48 hours, the values of solubility were commonly greater than those abtained occording to ISO (TC 106, WG 1/TG 9).
4)In addition, when the dental filling composite resins were extracted by 5 ml of ethanol:H2O(7:3)or 5 ml of tetrahydrofuran: H2O(9:1)mixed solvents at 37±1℃ for 1 week, it was observed that the values of solubility in the latter were greater than those of the former. But some organic filler type composite resins showed no weight loss after extraction by both organic solvents when they were placed in a dessicator as the method proposed by ISO.
5)The filler embedded in composite resin was observed by SEM after any extraction.
