中国人颞下颌关节的特性研究与人工关节的基础设计

Temporomandibular joint(TMJ) arthroplasty is an effective method of treating the advanced osteoarthritis, idiopathic condylar absorption, joint ankylosis and other advanced ailments of TMJ. However, at present this method has not yet been spread in China. The main reason is that foreign products do not exactly match with the Chinese anatomical shape and movement characteristics, which results in a lot of changes needed be made on patients' bone surface during the surgery, incresing the risk of skull base and inferior alveolar nerve damage and bleeding. Patients are easy to have muscle fatigue and lower lip numbness postoperatively. Therefore, new design of joint prosthesis according to Chinese anatomical features and motion characteristics of the temporomandibular joint (TMJ) is needed. This research is about to build the Chinese TMJ anatomical database, find the kinematic center and make finite element model analysis of TMJ structure based on the TMJ CT and MRI data and mechanical model. Meanwhile, we make innovations according to the experience from foreign standard artificial joint prostheses, namely ①structure of the TMJ fossa prosthesis；②angles of mandibular prosthesis; ③location of kinematic center of the condylar prosthesis; ④fixation method. Based on the above, the research is about to make a basic design of Chinese TMJ prosthesis, manufacture prototyping and do mechanical test by comprehensive methods including computer-aided design and manufacture technique, which would provide theoretical basis for the domestication of TMJ prosthesis.

人工颞下颌关节置换术是目前治疗晚期骨关节炎、髁突自溶性吸收以及关节强直等疾病的有效方法。但在中国尚未普及，除价格昂贵手术复杂外，主要原因是国外产品与中国人解剖形态不匹配,运动特性存在差异，从而造成手术中需要大量去骨，增加了颅底、下牙槽神经损伤和大出血的风险，导致患者术后出现下唇麻木和咀嚼肌疲劳等不适。因此，需要根据中国人颞下颌关节的解剖特点和运动特性设计人工关节假体。本研究拟在前期研究的基础上，通过CT数据处理、三维建模与测量，建立中国人颞下颌关节的解剖数据库；通过动态MRI确定髁突的运动中心位置和轨迹，并将CT和MRI数据融合建立有限元模型对其进行生物力学分析，参照国外假体进行四个方面的创新①关节窝假体结构②下颌支假体角度③髁突假体运动中心位置④固定形式。在此基础上综合应用CAD/CAM技术，进行中国人颞下颌关节假体的基础设计、原型制作和力学性能测试，为人工关节的国产化提供理论依据。

人工颞下颌关节置换术是目前治疗晚期骨关节炎、髁突自溶性吸收以及关节强直等疾病的有效方法。但在中国尚未普及，除价格昂贵手术复杂外，主要原因是国外产品与中国人解剖形态不匹配,运动特性存在差异，从而造成手术中需要大量去骨，增加了颅底、下牙槽神经损伤和大出血的风险，导致患者术后出现下唇麻木和咀嚼肌疲劳等不适。因此，需要根据中国人颞下颌关节的解剖特点和运动特性设计人工关节假体。本研究在前期研究的基础上，通过CT数据处理、三维建模与测量，建立了中国人颞下颌关节的解剖数据库；并依据中国人颞下颌关节解剖特征的聚类分析，设计了4种不同倾角和仰角的更加适用于中国人颞下颌关节结构的人工颞下颌关节假体，取得了国家发明专利授权，假体也已通过中国国家医疗器械质量安全检测，并进行了初期临床试验正在申请多中心临床试验；并通过CT数据建立了有限元模型对其进行生物力学分析，课题组通过动态CT进行了人工关节置换术后患者张闭口运动轨迹的获取，为人工关节的国产化的进一步推广打下了有力的证据。