BACKGROUND Sliding mechanics with miniscrews is recently used for extraction space closure. The purpose of this study was to elucidate how and why the archwire size affects long-term tooth movement in miniscrew sliding mechanics. METHODS Long-term orthodontic tooth movements were simulated based on a remodeling law of the alveolar bone by using a finite element method, in which the bracket rotated freely within a clearance gap (a play) of the archwire-bracket slot. The archwire size was changed to 0.021, 0.018, and 0.016 in. for the 0.022-in. bracket. RESULT Lingual crown tipping and extrusion of the incisors increased with decreasing the archwire size. Movements of the posterior teeth were approximately the same irrespective of archwire size. CONCLUSIONS When decreasing the archwire size, a play of the archwire-bracket slot, as well as the elastic deformation of the archwire, resulted in lingual tipping of the incisors. This tipping led to extrusion of the incisors.

中文翻译：

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弓丝尺寸对拔牙闭合中正畸牙齿运动影响的有限元分析，采用微螺钉滑动力学。

背景技术近来，具有微型螺钉的滑动机构被用于抽出空间的封闭。这项研究的目的是阐明弓丝的大小如何以及为什么会影响微型螺钉滑动力学中的长期牙齿运动。方法根据牙槽骨的重塑规律，采用有限元方法模拟了长期正畸牙齿的运动，其中支架在弓丝支架槽的间隙（间隙）内自由旋转。对于0.022英寸，弓丝尺寸更改为0.021、0.018和0.016英寸。托架。结果随着弓丝尺寸的减小，门牙的舌尖向顶端倾斜和挤压增加。后牙的运动与弓丝的大小无关，大致相同。结论当减小弓丝尺寸时，弓丝支架槽的作用 以及弓丝的弹性变形，导致门齿向舌尖倾斜。这种倾倒导致门牙的挤压。