髁突运动中心大张口轨迹与关节窝形态的关系及临床应用探讨

目的　探讨髁突运动中心大张口轨迹与关节窝形态的关系 ,对TMD患者髁突运动中心轨迹特征进行初步研究。方法　利用自行开发的髁突运动中心轨迹显示分析系统 ,分别以运动中心、终末绞链轴点作为参考点 ,观察 10名健康人和 7例临床检查怀疑盘前移位的TMD患者大张口轨迹 ,与磁共振成像得到的相应关节窝形态及关节盘位置诊断结果进行比较。结果　健康人左右侧运动中心轨迹与关节窝形态曲线重合率分别为 80 % (8/ 10 )和 90 % (9/ 10 ) ;终末绞链轴点轨迹与关节窝形态重合率均为 0 (0 / 10 )。TMD患者中 ,11侧盘前移位关节 ,除 1侧可复性盘前移位关节外 ,髁突运动中心轨迹均与正常的轨迹明显不同 ,出现各种改变 ;3侧正常盘位关节 ,髁突运动中心轨迹均与健康人的轨迹相似。结论　运动中心轨迹较终末绞链轴点个体稳定 ,可认为是较理想的研究髁突运动轨迹的参考点

A study on relationship between the contour of articular eminence and traces of the condylar kinematic center and its application in TMD patients

Objective To investigate the relationship between the contour of articular eminence and traces of the condylar kinematic center during jaw opening movement in healthy subjects, and compare trace characteristics of condylar kinematic center and MRI findings in TMD patients Methods In 10 healthy subjects, jaw opening motion was recorded The kinematic center and terminal hinge axis point of the condyle were used as trace reference points The contour of articular eminence was examined by MRI Seven patients with TMD signs and/or symptoms (disk displacement) were selected for this study The condylar trace was recorded during jaw protrusion and opening closing The internal derangement in temporomandibular joints was detected by MRI and defined as: (1) normal disk position, (2) disk displacement with reduction, (3) disk displacement without reduction Results In healthy subjects, most of the opening traces of the kinematic center coincided with the contour of articular eminence (8/10 joints in left, 9/10 joints in right) For terminal hinge axis point, no trace coincided with the contour of articular eminence (0/20 joints in left and right) In TMD patients, according to MRI findings, the condylar traces of kinematic center in 3 normal disk position joints showed normal shape However, in 6 disk displacements with reduction joints and 5 disk displacement without reduction joints, the condylar traces of kinematic center showed irregular patterns except 1 disk displacement with reduction joint Conclusions In comparison with the terminal hinge axis point, the opening traces of the kinematic center can be interpreted as the translatory movement of the condyle/disc along the articular eminence The study suggests the use of kinematic center in condylar movement studies