Liu Yang, Wu Yan, Yang Chongshi, Song Jinlin, Fan Yubo
College of Stomatology, Chongqing Medical University, Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China.
Department of orthodontics, Stomatological Hospital of Chongqing Medical University, Chongqing, China.
Comput Methods Biomech Biomed Engin. 2020 May;23(7):295-302. doi: 10.1080/10255842.2020.1719403. Epub 2020 Jan 27.
The objective of this study was to assess the biomechanical effects of different corticotomy designs used for orthodontic anterior retraction through finite element analysis.
A basic finite element model simulating retraction of anterior teeth was built reversely from CBCT films of an adult patient with protruded maxillary anterior teeth. Another thirteen FE models were created according to different corticotomy designs varied with site width and the extent of incision. The initial displacement, Von Mises stress and pressure stress of dento-alveolar structures was computerized and analyzed.
Corticotomy can increase the initial displacement of anterior segment including teeth and surrounding alveolar bone, change the distribution of Von Mises stress in cancellous bone and the pressure stress in periodontal ligament of anterior teeth. When the incision was near the periphery of apical, the anterior segment showed the greatest displacement, the cancellous bone at either sockets or incision region showed the maximum stress. Bilateral incision combined with palatal incision showed approximate initial displacement and stress distribution with circumscribing incision. While the incision width increased, the biomechanical effects of corticotomy amplified.
Varied corticotomy designs can change the biomechanical effects on dento-alveolar structures. The incision near the periphery of apical and bilateral incision combined with palatal incision may be the optimized design used for retraction of anterior teeth.
本研究的目的是通过有限元分析评估用于正畸前牙后移的不同皮质切开设计的生物力学效应。
从一名上颌前牙前突成年患者的CBCT影像反向构建一个模拟前牙后移的基础有限元模型。根据不同的皮质切开设计，随部位宽度和切口范围变化创建另外13个有限元模型。对牙-牙槽结构的初始位移、冯·米塞斯应力和压应力进行计算机化分析。
皮质切开可增加包括牙齿和周围牙槽骨在内的前段的初始位移，改变松质骨中冯·米塞斯应力的分布以及前牙牙周膜中的压应力。当切口靠近根尖周缘时，前段显示出最大位移，牙槽窝或切口区域的松质骨显示出最大应力。双侧切口联合腭侧切口与环切术显示出近似的初始位移和应力分布。随着切口宽度增加，皮质切开的生物力学效应增强。
不同的皮质切开设计可改变对牙-牙槽结构的生物力学效应。靠近根尖周缘的切口以及双侧切口联合腭侧切口可能是用于前牙后移的优化设计。
