Bai Ding, Cheng Bi-huan, Luo Song-jiao, Lü Tao
Department of Orthodontic, West China School of Stomatology, Sichuan University, Chengdu 610041, China.
Sichuan Da Xue Xue Bao Yi Xue Ban. 2004 May;35(3):358-60.
To find the characteristic of the stress distribution in the periodontal tissue during maxillary canine distal translation.
The model was implemented numerically by means of the 3-dimensional finite element method (FEM) and was used to simulate orthodontic tooth translation movements. The finite element model was loaded with defined force systems. And the stresses at 0, 7, 14, and 21 days of loaded distal force and moment in maxillary canine were calculated.
During the whole distal translation of canine, 1. the stress in alveolar bone was higher than that in peridontal ligament; 2. the stresses in the cervical region were higher than those in the apical region of the alveolar bone and periodontal tissues; 3. the stresses in the cervical, medium and apical regions of periodontal tissue were on the decline, and the stress in cervical region declined faster than that in apical region. On the 21st day the stresses in the cervical, medium and apical regions were similar.
The 3-D FEM analysis revealed that alveolar bone loss could be most likely to happen during the initial stage of the tooth movement, and the data from this study mihgt be helpful to orthodontists in selecting an appropriate device of force systems to control the initial loading during orthodontic treatment.
探究上颌尖牙远中移动过程中牙周组织应力分布的特征。
采用三维有限元法对模型进行数值模拟,以模拟正畸牙齿移动。给有限元模型加载特定的力系统。计算上颌尖牙在加载远中力和力矩0、7、14和21天时的应力。
在尖牙整个远中移动过程中,1. 牙槽骨中的应力高于牙周膜中的应力;2. 牙槽骨和牙周组织颈部区域的应力高于根尖区域的应力;3. 牙周组织颈部、中部和根尖区域的应力呈下降趋势,且颈部区域应力下降速度快于根尖区域。在第21天时,颈部、中部和根尖区域的应力相似。
三维有限元分析表明,牙齿移动初期最有可能发生牙槽骨吸收,本研究数据可能有助于正畸医生选择合适的力系统装置,以控制正畸治疗中的初始加载。