Study on Wear Resistance of Dental Restorative Materials

本文提出了一种定量测量修复过程中咬合磨损的新方法。为了再现口腔的机械环境，该测试方法使用了曲率和硬度与磨损咬合表面相似的玻璃珠。该测试方法主要包括使试样在覆盖在PMMA板上的玻璃珠上往复运动。总行程是10000，相当于走了1000米。并进行了牙刷磨损试验进行比较。所有常规复合材料在玻璃微珠磨损试验后的磨损量均明显高于微填充树脂的磨损量。用牙刷磨擦得到的结果与用玻璃珠磨擦得到的结果不一致。玻璃珠磨损的结果与临床观察结果有密切的相似之处。此外，扫描电镜研究支持上述结果。采用玻璃微珠磨损试验测定16种后牙复合树脂的体外磨损情况。微填充后路复合材料比高负荷后路复合材料耐磨性更高。当浆料较厚时，亚微填充树脂与微填充树脂的磨损差异不大。说明填料粒径对后置复合材料的耐磨性影响较大。在牙刷磨损试验中，磨损测量结果不一致。

A new method for quantitative measurement of occlusal wear on restoration is proposed in the present investigation. With the aim of reproducing a mechnical environment of the oral cavity, this test method uses glass beads which have the curvature and hardness similar to those of the abraded occlusal surface. The test method consists essencially in making a specimen to reciprocate on glass beads covered over a PMMA plate. The total stroke is 10,000 and it is equal to traveling 1,000m. The toothbrushing abrasion test was also carried out for comparison.ALL of the conventional composites showed much higher wear in volume loss after the glass beads abrasion test than the microfilled resin in abrasion. The results obtained by the toothbrushing abrasion conflicted with those obtained by the glass beads abrasion. There was a close parallel between the results of the glass beads abrasion and clinical observations. Moreover, SEM studies supported the results described above. In vitro wear of sixteen posterior composite resins was then determined by the glass beads abrasion test. Microfilled posterior composites wear higher wear-resistant than highly loaded posterior composites. There is little difference in wear between submicrofilled resins and microfilled resins with the thick slurry. This suggests that the filler particle size is relatively important to wear resistance of the posterior composite materials. There is no consistency among the wear measurements in the toothbrushing abrasion test.