Study on Reinforced Composite Resin Restorations by Inserting with the Megafillers

我们首先评价了在复合树脂修复体中加入“填充剂”对聚合收缩压力和聚合收缩速率的影响。用于测定的材料包括化学固化复合材料和光固化复合材料。收缩压力测量系统由用于制备试件的透明聚四氟乙烯管、小型称重传感器、动态应变计和笔式记录器组成。用汞浴法每10秒测量一次复合材料的线性聚合收缩，从开始混合或照射到90分钟。结果表明，Megafiller对降低聚合收缩效果显著，但在降低聚合过程中的收缩压力方面并不总是有效的。在下一项研究中，我们通过玻璃微珠磨损试验和传统的刷牙磨损试验来评估“Megafiller”植入对耐磨性的影响。磨损深度是通过使用精确到1微米的轮廓投影仪在磨损试验前后测量试件的厚度来确定的。总体而言，“巨型填料”的加入降低了复合材料的磨损深度，但除了少数材料外，加入和不加入巨型填料的复合材料的磨损深度差别不大。在一些复合树脂中，巨型填料的润湿性略有不同。目前，我们正在测定几种类型的陶瓷巨型填料(Phi1 Mm)插入对复合树脂热膨胀系数的影响。

We evaluated the effects of inserting "Megfiller" to composite resin restorations on the polymerization contraction force and the polymerization shrinkage rate firstly. The materials used for the determination included chemically cured composites and light-cured composites. The system for measuring contraction force consisted of a transparent teflon tube for preparing the specimen, a small load cell, a dynamic strain guage and a pen-recorder. Linear polymerization shrinkage of the composites was measured every 10 seconds from the start of mixing or irradiation to 90 minutes by the mercury bath medhod. The results suggested that "Megafiller" was markedly effective in reducing polymerization shrinkage, but was not always effective in reducing the contraction force during polymerization. In the next study, we examined the effects of "Megafiller" insertion on wear resistance evaluated by the glass beads abrasion test, and the conventioinal toothbrushing abrasion test. The depth of wear was determined by measuring the thickness of the specimens before and after the wear tests using a profile projector accurate to 1 um. In general, the depth of wear of the composites was reduced by "Megafiller" insertion, but the differences in the depth of wear between composites with and without the megafiller were not significant except for a few materials. There were slight differences in the wetness of the megafiller in some composite resins. At the present, we are determinig the effect of several type ceramic megafillers (phi1mm) insertion on the coefficient of thermal expansion of composite resins.