成人骨性Ⅱ类高角颞下颌关节骨关节病关节结构的CBCT分析

目的:研究成人骨性Ⅱ类高角型颞下颌关节骨关节病的关节结构特征，为正畸临床评估颞下颌关节提供理论依据。方法:从成人颞下颌关节正常及成人骨性Ⅱ类高角颞下颌关节骨关节病锥形束CT （CBCT）资料中各选取20例，将研究对象分2组，采用Invivo5 软件将CBCT 扫描数据进行三维重建，分别测量关节窝、关节间隙、髁突等关节结构。结果:同颞下颌关节正常组相比，20例成人骨性II类高角颞下颌关节骨关节CBCT样本中，关节窝前后径显著增加、高度显著减低（P＜0.01）；关节窝顶骨质显著增厚（P＜0.01）；关节结节高度降低、后斜面角减小（P＜0.05)；矢状向关节后间隙减小，而关节上间隙及前间隙都增加（P＜0.05）；髁突前后径、高度减小（P＜0.05）；水平角、髁突前斜面宽度及后斜面角增加（P＜0.05）。结论:成人骨性Ⅱ类高角型颞下颌关节骨关节病在关节窝改变最明显，其次是关节间隙和髁突的改变。

CBCT study on temporomandibular joint structure of temporomandibular joint osteoarthritis in adult high-angle Class II malocclusion

Objective: To study the characteristics of temporomandibularjoint osteoarthritis(TMJOA) by comparing TMJ structures in adult high-angle Class II malocclusion TMJOA group and normal TMJ group via cone-beam CT (CBCT) and Invivo5 software, so as to provide reference for clinical diagnosis. Methods: Twenty patients with normal TMJ and 20 patients with bilateral TMJOA and high-angle Class II malocclusion were selected. Invivo5 software was used to rebuild 3D image data and to measure glenoid fossa， condyle，joint space and position. Results: Compared with the control group, some bony changes were found in 20 adult high-angle Class II malocclusion TMJOA group, and the shape of the glenoid fossa became wider and shallower （P＜0.01）. However, the wall of the glenoid fossa roof was thickener （P＜0.01）. The height of the TMJ articular tubercle decreased and the slope became more flat（P＜0.05）. The posterior joint space gap was reduced, whereas the upper space and the anterior space increased in the sagittal direction（P＜0.05）. Condylar height decreased, however, the width of sagittal condylar forward slope increased（P＜0.05）, horizontal transverse condylar angle increased（P＜0.05）. Conclusion:The TMJOA in adult patients with skeletal Class II high angle glenoid fossa changes most significantly, followed by the joint space and condylar changes. CBCT and Invivo5 are practical tools for evaluation of TMJ , which can provide clinical reference and guidance for clinical orthodontic treatment