Study on Wear Resistance of Dental Restorative Materials

提出了一种定量测量修复体咬合磨损的新方法。为了再现口腔的机械环境，本试验方法使用了曲率和硬度与磨损咬合面相似的玻璃珠。试验方法主要包括在PMMA板上覆盖的玻璃珠上制作一个往复运动的试样。总行程为10，000，相当于行驶1，000米。刷牙磨损试验结果表明，玻璃微珠磨损试验后，所有常规复合材料的磨损量均明显高于微填充树脂。刷牙法与玻璃珠法所得结果不一致。玻璃珠磨损结果与临床观察结果之间存在密切的平行关系。此外，SEM研究支持上述结果。然后通过玻璃珠磨损试验测定16种后牙复合树脂的体外磨损。微填充后牙复合材料的耐磨性高于高载荷后牙复合材料。亚微填充树脂和微填充树脂在稠浆中的磨损差异很小。这表明，填料的粒径是相对重要的后牙复合材料的耐磨性。在刷牙磨损测试中，磨损测量值之间没有一致性。

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.