V形曲力学性能的三维有限元分析

Mechanical properties of V-bends with finite element analysis

目的对不同弓丝材质、尺寸、角度、形状、托槽间距的V形曲进行有限元力学分析,为V形曲的临床应用提供理论参考。方法建立两种材质(不锈钢弓丝、β钛丝)、两种尺寸(0.43 mm×0.64 mm、0.48 mm×0.64 mm)、两种V形曲位置、两种角度(150°、165°)和两种托槽间距(7、10 mm)的V形曲有限元模型,进行模拟加载后,对比分析其力学性能。结果不锈钢弓丝材质V形曲产生的最大作用力值均大于β钛材质V形曲,0.43 mm×0.64 mm弓丝弯制的V形曲作用力均小于0.48 mm×0.64 mm组,对称型V形曲受弓丝尺寸变化更为明显,托槽间距变化对非对称型V形曲作用力力值的影响更为明显。在V形曲形状相同时,V形角度越小,其各托槽作用力越大。结论弓丝材质尺寸、角度形状及托槽间距的改变均能影响V形曲力学行为。在临床应用中,可以根据托槽间距的大小,对V形曲弓丝材质尺寸、角度形状进行选择。

Objective To analyze the mechanical properties of V-bends with different materials,sizes of arch wires,angles,shapes,inter-bracket distances by using finite element method,so as to provide references for clinical practice of V-bends. Methods The finite element models of V-bends were established,including two kinds of materials（ stainless steel,titanium-molybdenum alloy）,two sizes（ 0. 43 mm × 0. 64 mm,0. 48 mm × 0. 64 mm）,two Vbend positions,two angles（ 150°,165°）,and two inter-bracket distances（ 7,10 mm）,so as to compare and analyze their mechanical properties after simulative loading. Results The maximum force values produced by V-bends with stainless steel arch wire were greater than that of V-bends with β titanium steel arch wire. The force produced by V-bends with 0. 43 mm × 0. 64 mm arch wire was smaller than that produced by V-bends with 0. 48 mm× 0. 64 mm arch wire. The size of arch wire had a more obvious impact on V-bends with symmetrical arch wire.The force of V-bends with asymmetric arch wire was more evidently influenced by the change of inter-bracket distance. For V-bends with the same shape,the smaller the V-shaped angle,the greater the force on the bracket would be. Conclusions The V-bends with different materials,different sizes of arch wires,different shapes and inter-bracket distances will have different mechanical behaviors. In clinical application,the materials,sizes of arch wires,shapes and angles of V-bends should be adjusted properly according to the inter-bracket distances.