远中移动尖牙的摩擦力测试

Friction forces in the process of distal drift of canine

目的测出远中移动尖牙时的摩擦力值及其公式。方法用槽沟为0.022英寸×0.028英寸的不锈钢方丝弓托槽和0.016英寸澳大利亚弓丝组合,记录托槽与弓丝间相互滑动时示波器上显示的格数,再通过力值与格数间的换算关系,得出相应摩擦力公式。结果远中移动尖牙的摩擦力值为(37.67±2.93)g。所得摩擦力公式为F=50/3h±G/6(h为示波器上的小格数,G为弓丝本身重量)。结论本实验的计算可知,远中移动尖牙时初始施力需为牙移动最适力值再加上所需克服40g左右的摩擦力值。

Objective To determine the friction forces with distal drift of canine and its calculat on formula. Methods Brackets （0. 022 ihch × 0. 028 inch） and archwires （0.016 inch） were tied by 0.20 mm-diameter and 24 mm-long stainless steel ligature through 6-circle revolving. Drifted them and transmitted the signal to the oscilloscope through sensor and then enlarger, and measured the frictions. Results The calculating formula was established as F= 50/3 h ± G/6（G：The height of archwires;h：The display of the oscilloscope）.The friction force was （37.67 ±2.93） g. Conclusion According to our experiments, in the course of the drift of canine, the initial force should be the most suitable force added to friction force about 40g.