目的 探究伴偏斜与否对下颌前突患者颞下颌关节（Temporomandibular joint，TMJ）应力分布的影响。方法 在MIMICS中建立4名下颌前突伴偏斜患者和4名下颌前突不伴偏斜患者的三维颌面部模型，在Abaqus中赋予模型偏侧咬合（单侧磨牙咀嚼）的肌肉力与边界条件，分析偏侧咬合工况下患者TMJ的最大主应力和最小主应力。结果 偏侧咬合工况下，伴偏斜患者髁突的平均最大应力显著大于不伴偏斜患者（P<0.05），伴偏斜会使髁突处应力增加了2～3倍，关节窝应力增加了5～7倍，且伴偏斜患者中颞下颌关节紊乱综合征(Temporomandibular Disorder，TMD)患者同侧TMJ处的应力高于无TMD患者。结论 伴偏斜会增大患者髁突和关节窝的应力，TMD会引起伴偏斜患者同侧TMJ的高应力。根据研究结果，建议根据偏斜与否考虑下颌前突的治疗。
Objective To explore the effect of facial asymmetry on stress distribution in temporomandibular joints (TMJs) for mandibular prognathism patients by three-dimensional finite element analysis. Methods Eight 3D maxillofacial models were established in MIMICS based on cone-beam CT of 4 mandibular prognathism patients with asymmetry and 4 mandibular prognathism patients without asymmetry. Muscle forces and boundary conditions corresponding to the unilateral occlusion (unilateral molar chewing) were applied on the models in ABAQUS. The maximum principal stress and the minimum principal stress of TMJ were chosen for analysis. Results There were significant differences of the maximum and minimum principal stresses at the condyles between the mandibular prognathism patients with and without facial asymmetry under unilateral occlusions (P<0.05). Compared to the patients without facial asymmetry, the stresses on the condyle in the patients with asymmetry increased by 2~3 times, and the stresses on articular fossa increased 5~7 times. Among the mandibular prognathism patients with asymmetry, the stresses of the ipsilateral TMJ in the patients with temporomandibular disorder (TMD) were significantly higher than those in the patients without TMD. Conclusions Facial asymmetry increased the stresses of the articular fossa and condyle in the mandibular prognathism patients. And TMD caused greater stress in the ipsilateral TMJ of the mandibular prognathism patient with asymmetry. Therefore, different treatment strategies should be considered for mandibular prognathism with facial asymmetry.