Odegaard J, Meling T, Meling E
Department of Orthodontics, University of Hamburg, Germany.
Am J Orthod Dentofacial Orthop. 1994 Apr;105(4):392-400. doi: 10.1016/S0889-5406(94)70134-2.
The amount of play between brackets and wire and the magnitude of the torsional moments developed have been investigated for six different rectangular wires. The study simulated the situation occurring when torque is applied to an individual central incisor. The observed play between wire and bracket ranged from about 5 degrees between an 0.018 x 0.025 inch in an 0.018-inch bracket slot, to approximately 20 degrees for a 0.016 x 0.022 inch in an 0.018-inch bracket slot. The observed rate of change after the play had been eliminated, varied from 0.24 degrees/Nmm to 0.37 degrees/Nmm for the steel wires, whereas 0.017 x 0.025-inch nitinol had a rate of change of approximately 1.07 degrees/Nmm. The use of ligatures demonstrated that a torque effect could be observed even though the play had not been completely eliminated.
针对六种不同的矩形钢丝，研究了托槽与钢丝之间的间隙量以及所产生的扭矩大小。该研究模拟了对单个中切牙施加扭矩时出现的情况。观察到的钢丝与托槽之间的间隙范围为，在0.018英寸托槽槽沟中，0.018×0.025英寸钢丝的间隙约为5度，而在0.018英寸托槽槽沟中，0.016×0.022英寸钢丝的间隙约为20度。间隙消除后的观察到的变化率，钢丝为0.24度/牛顿毫米至0.37度/牛顿毫米，而0.017×0.025英寸的镍钛合金丝的变化率约为1.07度/牛顿毫米。结扎丝的使用表明，即使间隙没有完全消除，也能观察到扭矩效应。
