下顎骨的髁頸破壞是常見的破壞形式之一。當下顎骨受到髁頸斷裂時，外科手術常使用的接合板重建下顎骨，將下顎骨接合並固定。在許多臨床病例中發現重建接合板系統失效的問題。因此本文藉由建立下顎骨的三維有限元素模型，以幾何外型參數的方式建構接合板的有限元素模型，研究下顎骨髁頸破壞重建系統的機械行為。主要以主應力與等效應力的分佈，探討下顎骨受右側臼齒咀嚼力的狀況，以及接合板的幾何形狀參數對於系統的影響。分析結果發現重建下顎骨髁頸破壞的系統，主要的機械負荷為接合板面內的彎矩負荷、面外的扭矩負荷以及拉伸負荷。這些負荷將影響接合板各種幾何形狀參數對於下顎骨的力學行為。

Mandible condylar neck fracture is one of the conventional mandibular fracture types. Surgical operations usually use the bridging plate to reconstruct the fractured mandibular neck. Some failure problems of the reconstruction system can be found in many clinical cases. In this paper, three dimensional finite element models of the fractured mandible repaired by two different bridging plates are developed. Delta-shaped bridging plate and mini-plate are considered here. The mechanical behavior of the reconstructed repaired system is investigated by employing the theory of elasticity. In the right side molar chewing case, the principal stress and von Mises stress distributions are computed to evaluate the safety of the integrated system. All discussions are emphasized on the effects of the plate geometric parameters on the stress fields. The numerical results show that both of the plates are subjected to in-plane bending load, out of plane torsion load, and the tension load. The contributions of these loads on the stress fields in these two plates are discussed in detail.

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