关键词: 颞下颌关节, 髁突体积, 关节窝体积, 髁突位置

Abstract:

Objective To explore the changes of condylar position among Class Ⅱ malocclusion patients with clinical symptoms of temporomandibular joint disorder(TMD) through cone beam CT(CBCT) images. Methods Among the patients with Class Ⅱ malocclusion, a retrospective analysis was performed for the CBCT data of 30 patients without clinical symptoms of TMD (NTMD group) and 37 patients with clinical symptoms of TMD (TMD group). Condylar volume, condylar horizontal angle, articular fossa volume, anterior joint space, and posterior joint space were measured by Mimics 21.0 and 3-matic 13.0 software. SPSS 22.0 software was used for statistical analysis. Results The bilateral condyle volume of the NTMD group was significantly different (the right (2 302.71±546.35)mm³, the left (1 679.06±356.07)mm³; P<0.001). The bilateral condylar volume (the right (2 299.19±810.53)mm³, the left (1 683.93±519.61)mm³; P<0.001) and bilateral condylar horizontal angle (the right (13.41°±7.31°), the left (11.30°±6.56°); P=0.015) in the TMD group were significantly different. Conclusion Among the patients with Class Ⅱ malocclusion, patients show asymmetry in the horizontal angles of bilateral condyles in the early stage of TMD. The symmetrical condylar position is crucial for the prevention of TMD, but is not the primary problem for the treatment of TMD.

Key words: temporomandibular joint, condylar volume, articular fossa volume, condylar position