Titre : Influence de l’anisotropie osseuse sur l’évaluation de la fiabilité de la stabilisation du système de fixation par mini-plaques dans les fractures mandibulaires de la symphyse : Deux cas étudiés sous la période de la guérison Auteurs : Kharmanda G., El-Hami A., Kharma M-Y., Revue : Incertitudes et fiabilité des systèmes multiphysiques Numéro : Numéro 2 Volume : 3 Date : 2020/01/6 DOI : 10.21494/ISTE.OP.2019.0438 ISSN : 2514-569X Résumé : The reliability analysis is used to in order to measure the stability of the mini-plate fixation system used in the human fractured mandibles after the chirurgical operation. The failure is assumed to take place when the Most Probable failure Point (MPP) is found. In this work, two studied cases of 3-dimensional finite element models are considered for the same fracture situation. A successful fracture healing requires that a number of constraints which are influenced by the loading conditions are fulfilled, and since muscle activity is difficult to evaluate, there is a strong need to introduce loading uncertainties in order to obtain a reliable design. Several categories of critical failure scenarios are considered in this study : The first category of failure scenarios is that of the relative displacement between two fracture surfaces should not exceed a critical threshold to ensure rapid healing. The second category is failure of the mini-plates which in this work is interpreted as when the yield stress within the mini-plates is reached, and the third category of failure scenarios is that of the yield stress in the mandible bone tissues should not be exceeded. Two fractured mandibles are studied under the convalescence period : Case I (a single isotropic bone tissue) and Case II (composite anisotropic bone tissues). During the fixation of the mini-plates, the drilling positions in the two cases can vary when considering a composite bone tissue mandible relative to a homogeneous bone tissue one. To show the effect of the bone anisotropy, an analytical formulation is developed as a helpful technique to analyze the effect of the mini-plate position changes. The bone properties used in the anisotropic case (Case II) are orthotropic. The results show that the reliability indices are very affected when considering the bone anisotropy. Éditeur : ISTE OpenScience