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目的对自锁托槽与传统托槽滑动阻力的大小及变化规律进行对比研究。方法本研究于2011年9—12月在山西医科大学口腔医院和太原理工大学应用力学与生物医学研究所共同完成。根据人体实际弹性模量比例制作含牙周膜的上颌仿真模型，测试自锁托槽和传统托槽分别与0．016英寸、0．018英寸的镍钛丝和0．017英寸×0．022英寸、0．018英寸×0．025英寸、0．019英寸x0．025英寸的不锈钢方丝匹配时的滑动阻力大小。结果使用同种弓丝时，滑动阻力由小到大排列：DamonQ被动自锁托槽〈Tomy主动自锁托槽〈传统金属托槽，两两比较差异有统计学意义（P〈0．05）。同一种托槽情况下，除0．019英寸×0．025英寸不锈钢方丝外，其余滑动阻力都随弓丝直径的增大而增大，且两两比较差异有统计学意义（P〈0．05）。结论临床实践中托槽类型与弓丝的匹配对滑动阻力的影响十分重要，从而实现牙齿的快速有效移动。

Comparison between conventional and self-ligating brackets on testing the resistance to sliding

Objective To investigate the difference and the laws of variation on the resistance to sliding of conventional and self-ligating brackets. Methods A maxillary simulation model with pericementum was set up according to the pro- portion of somatological elastic modulus. The resistance to sliding was measured by conventional brackets and self-ligat- ing brackets and the arch wire of 0.016 and 0.018 inches NiTi wires and 0.017×0.022,0.018×0.025,0.019×0.025 inches stainless steel wires. Results The resistance to sliding was followed from the high to the low： Damon Q passive self-li- gating brackets 〈 Tomy active self-ligating brackets 〈 conventional brackets, and the differences were significant （P 〈 0.05） ; The resistance to sliding increased along with the increase of the diameter of archwires, except that the resis- tance to sliding of the 0.019x0.025 inch rectangular archwire was lower than the 0.017×0.022 and 0.018×0.025 inch ones. The differences between them were significant （P 〈 0.05）. Conclusion Clinically the resistance to sliding is in- fluenced by the match of different types of brackets and the arch wire, which is important in realizing the rapid and effec- tive movement of teeth.