Krishnan Vinod, Kumar K Jyothindra
Department of Orthodontics, Sree Mookambika Institute of Dental Sciences, Kulasekharam, Tamilnadu, India.
Angle Orthod. 2004 Dec;74(6):825-31. doi: 10.1043/0003-3219(2004)074<0825:MPASCO>2.0.CO;2.
Recent developments in material science have presented newer archwire materials as well as improvements in the properties of existing ones. Proper selection and understanding of the biomechanical requirement of each case requires proper characterization studies on archwire alloys. The present study characterizes and compares three orthodontic archwire alloys, stainless steel, beta titanium alloy (TMA), and a newly introduced titanium alloy (TiMolium), for the parameters (1) ultimate tensile strength (UTS), 0.02% offset yield strength (YS), and modulus of elasticity (E); (2) load deflection characteristics; (3) frictional properties; (4) surface characteristics and (5) elemental analysis for TiMolium. Seven specimens of each archwire alloy were used for evaluating each parameter. An instron universal testing machine was used for tensile testing, three-point bend testing, and evaluation of frictional characteristics. Scanning electron microscope was used for surface evaluation and X-ray fluorescence for elemental analysis of TiMolium wire specimens. Stainless steel was the strongest archwire alloy with high UTS, E, 0.02% offset YS, and less friction at the archwire-bracket interface. TMA wires exhibited better load deflection characteristics with less stiffness than the other two wires. The surface of TMA appeared rough and exhibited very high values for friction at the archwire-bracket interface. TiMolium appeared to be an alpha-beta titanium alloy composed of titanium, aluminum, and vanadium and intermediate in nature for all the parameters evaluated.
材料科学的最新进展带来了新型弓丝材料，并改进了现有材料的性能。要正确选择并理解每个病例的生物力学需求，就需要对弓丝合金进行恰当的特性研究。本研究对三种正畸弓丝合金——不锈钢、β钛合金（TMA）和新推出的钛合金（TiMolium）——的以下参数进行了特性分析和比较：（1）极限抗拉强度（UTS）、0.02% 偏移屈服强度（YS）和弹性模量（E）；（2）载荷挠度特性；（3）摩擦性能；（4）表面特性；以及（5）对TiMolium进行元素分析。每种弓丝合金的七个样本用于评估每个参数。使用英斯特朗万能材料试验机进行拉伸试验、三点弯曲试验以及摩擦特性评估。使用扫描电子显微镜进行表面评估，使用X射线荧光光谱仪对TiMolium弓丝样本进行元素分析。不锈钢是最强的弓丝合金，具有较高的UTS、E、0.02% 偏移YS，并且在弓丝 - 托槽界面处摩擦力较小。TMA弓丝表现出更好的载荷挠度特性，刚度比其他两种弓丝小。TMA的表面显得粗糙，在弓丝 - 托槽界面处摩擦力非常高。TiMolium似乎是一种由钛、铝和钒组成的α-β钛合金，在所评估的所有参数方面处于中间水平。
