Orthodontic Graduate Program, University of Alberta, Edmonton, AB, Canada.
Angle Orthod. 2010 Jan;80(1):201-10. doi: 10.2319/080508-352.1.
To evaluate the quantitative effects on torque expression of varying the slot size of stainless steel orthodontic brackets and the dimension of stainless steel wire, and to analyze the limitations of the experimental methods used.
In vitro studies measuring torque expression in conventional and self-ligating stainless steel brackets with a torque-measuring device, with the use of straight stainless steel orthodontic wire without second-order mechanics and without loops, coils, or auxiliary wires, were sought through a systematic review process.
Eleven articles were selected. Direct comparison of different studies was limited by differences in the measuring devices used and in the parameters measured. On the basis of the selected studies, in a 0.018 inch stainless steel bracket slot, the engagement angle ranges from 31 degrees with a 0.016 x 0.016 inch stainless steel archwire to 4.6 degrees with a 0.018 x 0.025 inch stainless steel archwire. In a 0.022 inch stainless steel bracket slot, the engagement angle ranges from 18 degrees with a 0.018 x 0.025 inch stainless steel archwire to 6 degrees with a 0.021 x 0.025 inch stainless steel archwire. Active stainless steel self-ligating brackets demonstrate an engagement angle of approximately 7.5 degrees, whereas passive stainless steel self-ligating brackets show an engagement angle of approximately 14 degrees with 0.019 x 0.025 inch stainless steel wire in a 0.022 inch slot.
The engagement angle depends on archwire dimension and edge shape, as well as on bracket slot dimension, and is variable and larger than published theoretical values. Clinically effective torque can be achieved in a 0.022 inch bracket slot with archwire torsion of 15 to 31 degrees for active self-ligating brackets and of 23 to 35 degrees for passive self-ligating brackets with a 0.019 x 0.025 inch stainless steel wire.
评估不同不锈钢正畸托槽槽沟尺寸和不锈钢丝尺寸对扭矩表达的定量影响，并分析所使用实验方法的局限性。
通过系统评价过程，寻找测量常规和自锁式不锈钢托槽扭矩表达的体外研究，使用无二次力学且无圈、环或辅助丝的直不锈钢正畸丝。
选择了 11 篇文章。由于使用的测量设备和测量参数不同，直接比较不同的研究受到限制。基于所选研究，在 0.018 英寸不锈钢托槽槽沟中，结合角度范围为 31 度，使用 0.016 x 0.016 英寸不锈钢方丝，到 4.6 度，使用 0.018 x 0.025 英寸不锈钢方丝。在 0.022 英寸不锈钢托槽槽沟中，结合角度范围为 18 度，使用 0.018 x 0.025 英寸不锈钢方丝，到 6 度，使用 0.021 x 0.025 英寸不锈钢方丝。主动式不锈钢自锁托槽的结合角度约为 7.5 度，而被动式不锈钢自锁托槽使用 0.019 x 0.025 英寸不锈钢丝在 0.022 英寸槽沟中显示约 14 度的结合角度。
结合角度取决于弓丝尺寸和边缘形状以及托槽槽沟尺寸，是可变的，并且大于已发表的理论值。在 0.022 英寸托槽槽沟中，对于主动自锁托槽，使用 15 至 31 度的弓丝扭转，对于被动自锁托槽，使用 23 至 35 度的弓丝扭转，可实现临床有效扭矩，使用 0.019 x 0.025 英寸不锈钢丝。
