Ming-Tzu Tsai1, Heng-Li Huang2,3, Shih-Guang Yang4, Kuo-Chih Su1,5, Lih-Jyh Fuh2,6, Jui-Ting Hsu7,8,9. 1. Department of Biomedical Engineering, Hungkuang University, Taichung, 433, Taiwan. 2. School of Dentistry, College of Medicine, China Medical University, Taichung, 404, Taiwan. 3. Department of Bioinformatics and Medical Engineering, Asia University, Taichung, 413, Taiwan. 4. Master Program for Biomedical Engineering, China Medical University, Taichung, 404, Taiwan. 5. Department of Medical Research, Taichung Veterans General Hospital, Taichung, 407, Taiwan. 6. Department of Dentistry, China Medical University and Hospital, Taichung, 404, Taiwan. 7. School of Dentistry, College of Medicine, China Medical University, Taichung, 404, Taiwan. jthsu@mail.cmu.edu.tw. 8. Department of Bioinformatics and Medical Engineering, Asia University, Taichung, 413, Taiwan. jthsu@mail.cmu.edu.tw. 9. School of Dentistry, College of Dentistry, China Medical University, 91 Hsueh-Shih Road, Taichung, 40402, Taiwan. jthsu@mail.cmu.edu.tw.
Abstract
OBJECTIVE: The study objective was to investigate four common occlusal modes by using the finite element (FE) method and to conduct a biomechanical analysis of the periodontal ligament (PDL) and surrounding bone when orthodontic force is applied. MATERIALS AND METHODS: A complete mandibular FE model including teeth and the PDL was established on the basis of cone-beam computed tomography images of an artificial mandible. In the FE model, the left and right mandibular first premolars were not modeled because both canines required distal movement. In addition, four occlusal modes were simulated: incisal clench (INC), intercuspal position (ICP), right unilateral molar clench (RMOL), and right group function (RGF). The effects of these four occlusal modes on the von Mises stress and strain of the canine PDLs and bone were analyzed. RESULTS: Occlusal mode strongly influenced the distribution and value of von Mises strain in the canine PDLs. The maximum von Mises strain values on the canine PDLs were 0.396, 1.811, 0.398, and 1.121 for INC, ICP, RMOL, and RGF, respectively. The four occlusal modes had smaller effects on strain distribution in the cortical bone, cancellous bone, and miniscrews. CONCLUSION: Occlusal mode strongly influenced von Mises strain on the canine PDLs when orthodontic force was applied. CLINICAL RELEVANCE: When an FE model is used to analyze the biomechanical behavior of orthodontic treatments, the effect of muscle forces caused by occlusion must be considered.
OBJECTIVE: The study objective was to investigate four common occlusal modes by using the finite element (FE) method and to conduct a biomechanical analysis of the periodontal ligament (PDL) and surrounding bone when orthodontic force is applied. MATERIALS AND METHODS: A complete mandibular FE model including teeth and the PDL was established on the basis of cone-beam computed tomography images of an artificial mandible. In the FE model, the left and right mandibular first premolars were not modeled because both canines required distal movement. In addition, four occlusal modes were simulated: incisal clench (INC), intercuspal position (ICP), right unilateral molar clench (RMOL), and right group function (RGF). The effects of these four occlusal modes on the von Mises stress and strain of the canine PDLs and bone were analyzed. RESULTS: Occlusal mode strongly influenced the distribution and value of von Mises strain in the canine PDLs. The maximum von Mises strain values on the canine PDLs were 0.396, 1.811, 0.398, and 1.121 for INC, ICP, RMOL, and RGF, respectively. The four occlusal modes had smaller effects on strain distribution in the cortical bone, cancellous bone, and miniscrews. CONCLUSION: Occlusal mode strongly influenced von Mises strain on the canine PDLs when orthodontic force was applied. CLINICAL RELEVANCE: When an FE model is used to analyze the biomechanical behavior of orthodontic treatments, the effect of muscle forces caused by occlusion must be considered.
Authors: Clarice Field; Ionut Ichim; Michael V Swain; Eugene Chan; M Ali Darendeliler; Wei Li; Qing Li Journal: Am J Orthod Dentofacial Orthop Date: 2009-02 Impact factor: 2.650