Baek Seung-Hak, Shin Soo-Jung, Ahn Sug-Joon, Chang Young-Il
Department of Orthodontics, School of Dentistry, Dental Research Institute, Seoul National University, South Korea.
Eur J Orthod. 2008 Feb;30(1):10-5. doi: 10.1093/ejo/cjm098.
The purpose of this study was to compare the effect of a multiloop edgewise archwire (MEAW) with a plain ideal archwire (IA) on distal en masse movement of the mandibular dentition. A three-dimensional finite element model (3D FEM) of the mandibular dentition, without third permanent molars, was constructed to include the periodontal membrane (PDM), alveolar bone, standard edgewise bracket (0.018 x 0.025 inch), stainless steel IA (0.016 x 0.022 inch), and MEAW (0.016 x 0.022 inch). Stress distribution and displacement of the mandibular dentition were analyzed when Class III intermaxillary elastics (300 g/side) and 5 degree tip-back bends from the first premolar to the second molar were applied to the IA and the MEAW for distal en masse movement of the mandibular dentition. Compared with the IA, the discrepancy in the amount of tooth displacement was less and individual tooth movement with the MEAW was more uniform and balanced. There was minimal vertical displacement or rotation of the teeth with the MEAW when compared with the IA. The MEAW seems to have advantages for distal en masse movement of the mandibular dentition.
本研究的目的是比较多曲方丝弓（MEAW）与普通理想弓丝（IA）在下颌牙列整体远中移动方面的效果。构建了一个不含第三恒磨牙的下颌牙列三维有限元模型（3D FEM），该模型包括牙周膜（PDM）、牙槽骨、标准方丝弓托槽（0.018×0.025英寸）、不锈钢IA弓丝（0.016×0.022英寸）和MEAW弓丝（0.016×0.022英寸）。当对IA弓丝和MEAW弓丝施加Ⅲ类颌间弹力牵引（每侧300 g）以及从第一前磨牙到第二磨牙5度的后倾弯以实现下颌牙列整体远中移动时，分析下颌牙列的应力分布和位移情况。与IA弓丝相比，使用MEAW弓丝时牙齿位移量的差异更小，且单个牙齿的移动更均匀、平衡。与IA弓丝相比，使用MEAW弓丝时牙齿的垂直位移或旋转最小。MEAW弓丝在下颌牙列整体远中移动方面似乎具有优势。
