[Relationship among the composition and the physical and chemical properties of photo-cured composites for crown and bridge].

In this study, the relationship among the chemical composition and the physical and chemical properties of four photo-cured composites and one heat curing composite for crown and bridge were investigated. Five composites were composed of the base monomer, UDMA, TriEGDMA, 1, 3-BDMA, 1, 4-BDMA, 1, 10-DDMA, 1, 12-DDDMA or those mixture, and the composite-filler consist of the resin (TMPTMA, UDMA, 1, 10-DDMA or 1, 12-DDDMA) and micro-silica particles. Four photo-curing composites had a high elastic modulus and Vickers hardness and a low thermal expansion coefficient and water sorption compared with the heat-cured composite (Is). The effects of filler contents in the composites examined were positively on the elastic modulus and the hardness, and were inversely on the bending strength and the thermal expansion coefficient of the cured products. While the organic phase in the composite fillers had effect on the abrasive resistance of the composites. But no significant correlation between the abrasive resistance and the filler contents and the physical properties of the materials tested was noted.