歯科修復材コンポジットレジンの圧縮強度特性（光硬化時間と水中浸漬期間の影響）

抄録

Resin composites as dental restorative materials were investigated with respect to compressive strength. Columnar specimens were prepared by light curing process, and compression tests were performed under various conditions. Then stress-strain curves, fracture stress, fracture strain and elastic modulus were estimated. In the preparation of specimens, light curing time was changed, and the dependence of compressive strength on the light curing time was investigated. Furthermore, after preparation of specimens by adequate light curing process, specimens were immersed in water at the temperature of 37 degrees C, and the dependence of compressive strength on the water immersing period was investigated, too. Variation of density and wear resistance as well as compressive strength were investigated, and effects of the light curing time and the water immersing period on mechanical properties were discussed. Shrinkage of specimens and variation of mechanical properties according to the polymerization depending on light curing time were clarified, and degradation of mechanical properties according to the absorption of water depending on water immersing period was clarified, too. Finally, cross sections of specimens were observed by SEM micrograph, and internal defects and their development depending on applied compressive stress and water immersing period were clarified.