安氏II类2分类患者髁突位置与TMJOA的关系分析

IObjective: To measure temporomandibular joints(TMJ) of 15 patients with Angle's Class II Division 2 by cone beam computed tomography(CBCT)and analyse the relationship between condyle position and temporomandibular joint osteoarthrosis(TMJOA). Methods: 15 patients with Angle's Class II Division 2 from orthodontic outpatient department were selected to be expeirmental group, 16 subjects with individual normal occlusion were adopted to be control group.All of them undergone CBCT scan. Cephalometrics and TMJ measurement were accomplished by InVivodental Application software. All data were analysed by SPSS19.0 software. Results: 2 parameters showed significant diffenences between the bilateral joints in expeirmental group (P>0.05), ①Distance between unilateral condyle and sagittal midline.②slope of articular tubercle. The detectable rate of TMJOA was 73.33% (22/30), the main radiographic appearances of condyle were partial ill-defined cortical bone, osteophyte of the condyle, and subcortical cyst. 2 parameters showed significant diffenences between the bilateral joints in control group (P>0.05), ①stressed angle of condyle. ②slope of articular tubercle.No TMJ of control group were detacted to be TMJOA. The bilateral TMJ anterior space of expeirmental group were greater than that of control group, and the difference were significent (P>0.05). Conclusion: The shape of bilateral condyle of patients with Angle's class II division 2 are relatively consistent. The position of condyle are backward. The patients with the malocclusion have a high detectable rate of TMJOA, the change of condyle position may be the risk factor of TMJOA.