fa Estimation of periodontal ligament's equivalent mechanical parameters for finite element modeling ارتودنسی Orthodontics پژوهشي Research <p> <strong>Introduction</strong></p><p>  Young’s modulus (E) and Poisson’s ratio (v) of the periodontal ligament are needed in a finite element analysis for investigating the biomechanical behavior of a tooth, periodontal ligament, and bone complex. However, large discrepancies in E (0.01-1,750 MPa) and v (0.28-0.49) were reported previously. The objective of this study was to narrow the ranges and to provide equivalent E and v pairs suitable for finite element modeling of a tooth, periodontal ligament, and bone complex by using a reported crown load-displacement relationship as the criterion. </p><p> <strong>Methods</strong></p><p>  A 3-dimensional finite element model of a 3-tooth, periodontal ligament, and bone complex, consisting of a maxillary central incisor with 2 adjacent teeth, from a cone-beam computed tomography scan was created. The dimensions, constraints, and loading condition were kept similar to those reported in the human study. With the load applied to the crown, both v and E were adjusted independently, and the corresponding crown displacements were calculated. The resulting load-displacement curves were compared with those reported in the human study. The mean absolute displacement difference method was used to find the best fit. The E and v pairs that generated the minimum mean absolute displacement difference were identified. </p><p> <strong>Results</strong></p><p> <strong> </strong>The finite element model with 1 of the 3 E and v pairs (v = 0.35, E = 0.87 MPa v = 0.4, E = 0.71 MPa and v = 0.45, E = 0.47 MPa) simulated the tooth, periodontal ligament, and bone complex well. The mean absolute displacement differences were 0.0135, 0.0138, and 0.0138 mm, respectively these are less than 8% of 0.175 mm, which was the crown displacement of the tooth, periodontal ligament, and bone complex under the load of 500 cN. </p><p> <strong>Conclusions</strong></p><p>  The E and v values close to the 3 pairs might be used for finite element modeling of the tooth, periodontal ligament, and bone complex. </p><hr><p></p><p> <strong>Source: </strong>American Journal of Orthodontics & Dentofacial Orthopedics </p><p> <a href="http://www.ajodo.org/article/S0889-5406(13)00010-3/abstract" target="_blank"><font color="#0000ff">Full Text</font></a></p> 0 0 http://idai.ir/browse.php?a_code=A-10-32-1766&slc_lang=fa&sid=1 Zeyang Xia 10031947532846008326 10031947532846008326 No Department of Mechanical Engineering, Indiana University Purdue University, Indianapolis, Ind Feifei Jiang 10031947532846008327 10031947532846008327 No Department of Mechanical Engineering, Indiana University Purdue University, Indianapolis, Ind Jie Chen 10031947532846008328 10031947532846008328 Yes Department of Mechanical Engineering and Department of Orthodontics and Oral Facial Genetics, Indiana University Purdue University, Indianapolis, Ind