Aulen树脂卡环与Co—Cr卡环循环疲劳及对牙面磨损的研究

目的：比较Aulen树脂卡环与Co—Cr卡环在离体牙上循环疲劳测试中的脱位力衰减趋势，观察其对离体牙的磨损。方法：制作Aulen树脂卡环和Co—Cr卡环，利用多功能生物力学测定仪进行循环疲劳测试，对比其脱位力衰减情况，扫描电镜观察实验前后离体牙的磨损情况；结果：卡环在循环疲劳测试后其脱位力均不同程度下降，Aulen树脂卡环的摩擦区域无明显划痕，Co—Cr卡环的摩擦区域形成明显的划痕，破坏了原来平滑的表面。结论：Aulen树脂卡环固位力较Co—Cr卡环小，但衰减缓慢，Aulen树脂卡环对牙面的磨损程度小于Co—Cr卡环。

Study on retention force and cyclic fatigue test of resin clasp and cobalt-chrominum alloy cast clasp.

Objective： Compare the retention force of resin clasp and cobalt-chrominum alloy cast clasp in cyclic fa- tigue test and observe the abrasion on the teeth using the scanning electron microscope （SEM）. Method： 5 resin clasps and 5 Co-Cr clasps were made. A cyclic fatigue test on the extracted tooth was evaluated using the universal testing machine,The friction area before and after the cyclic fatigue test were scaned using the SEM and compared the extent of abrasion. Result： Both clasps on the extracted tooth experienced a significance decrease in retentive forces during the cyclic fatigue test. There are no obvious grooves on the tooth surface of resin clasp group instead of many grooves when using Co-Cr clasp and that the original texture can not be seen. Conclusion： The retention force of resin clasp decreased slowly than Co-Cr clasp. The abrasion of resin clasp on the tooth surface is less than the Co-Cr clasp.