WEAR CHARACTERISTICS OF RESIN COMPOSITES FOR CROWN AND BRIDGE

对9种冠、桥用树脂复合材料进行了性能评价。观察填料的形状，填料的含量，以评估填料类型，因为这些在树脂复合材料的性能显著影响。通过光照射单元的固化深度和基体树脂的结构，测定了冠、桥用树脂复合材料的固化性能。此外，通过断裂韧性测试、直接拉伸测试、弯曲测试和硬度测试来评估机械性能。不同树脂冠桥复合材料的填料、固化和力学性能差异显著。与树脂复合材料相比，这些树脂复合材料的填料含量更低，颗粒更小。我们可以将树脂复合材料分为冠和桥两种。一种用于前牙贴面，另一种用于后牙修复。这些填料类型和成分在施用类型上存在显著差异。冠、桥用树脂复合材料的力学性能低于修复用树脂复合材料。采用OHSU型磨损试验机模拟口腔环境下树脂冠桥复合材料的磨损情况，对树脂冠桥复合材料的磨损进行了测定。我们发现一些树脂复合材料对拮抗牙釉质有较高的磨损率。磨损特性不仅受力学性能的影响，还受填料性能的影响。这些结果表明，由于牙冠和桥的树脂复合材料在口腔环境中承受的时间更长，因此需要考虑磨损机的测试条件、拮抗材料和环境等诸多因素。

Nine kinds of resin composites for crown and bridge were examined to evaluate those properties. Observations of filler shape, filler contents were performed to evaluate filler type, since those in resin composites affected properties significantly. Curing properties of resin composites for crown and bridge were also measured for the depth of cure with light exposuring units and the structure of matrix resin. Moreover, mechanical properties were evaluated by fracture toughness test, direct tensile, bending, and hardness tests.Filler, curing, and mechanical properties differed in each resin composites for crown and bridge significantly. These resin composites had lower filler contents, and smaller particle fillers than resin composites for restoration. We could classify two types of resin composites for crown and bridge. The one was for veneering to anterior, and the other was for applying to posterior restorations. Those filler type and composition differed in types for applying significantly. Mechanical properties of resin composites for crown and bridge were lower than those of resin composites for restoration.Wear of resin composites for crown and bridge was determined by using an OHSU type wear tester simulating wear patterns in an oral condition. We found some resin composites for crown and bridge had high wear rate for antagonistic enamel. Wear characteristics was not only affected by mechanical properties but also by filler properties. These results suggested that we had to consider for many factors such as testing conditions of a wear machine, antagonistic materials, and environments, since resin composites for crown and bridge suffered more severe conditions in oral environment for longer time.