State Key Laboratory of Military Stomatology, National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, Air Force Medical University, Xi'an, 710032, Shaanxi, People's Republic of China.
BMC Oral Health. 2023 Jul 12;23(1):477. doi: 10.1186/s12903-023-03210-9.
To investigate changes in the three-dimensional (3D) spatial morphology of the temporomandibular joint (TMJ) and condyle position in adult patients with Class II division 2 malocclusion using a 3D spatial measurement method and to investigate the similarities and differences in the effects of fixed appliance and clear aligner treatments on the TMJ.
Cone-beam computed tomography (CBCT) data of 47 adult patients with Class II division 2 malocclusion (25, fixed appliance group; 22, clear aligner group) were collected before and after treatment. Mimics 21.0 was used to reconstruct the TMJ 3D model. Fourteen measurement items, such as the anterior, upper, and posterior joint spaces, were measured directly on the 3D model and compared.
Post-orthodontic treatment, the shape and position of the condyle changed in adult patients with Class II division 2 malocclusion. Reduction in the anterior joint space and increase in the posterior joint space after orthodontic treatment were significant in both fixed appliance and clear aligner treatments; the condyle moved forward to the center of the fossa. The superior joint space and depth of the glenoid fossa increased after clear aligner treatment, but there was no significant change after fixed appliance treatment.
The condylar shape and position in patients with Class II division 2 malocclusion changed significantly post-treatment, indicating that the condyle undergoes adaptive reconstruction during orthodontic treatment in these patients. These results provide a reference for diagnosis, design of treatment plan, and monitoring of treatment in orthodontic clinics.
采用三维（3D）空间测量方法，研究成人安氏Ⅱ类 2 分类错牙合患者颞下颌关节（TMJ）及髁突位置的三维空间形态变化，探讨固定矫治器和透明矫治器治疗对 TMJ 的影响的异同。
收集 47 例成人安氏Ⅱ类 2 分类错牙合患者（固定矫治器组 25 例，透明矫治器组 22 例）治疗前后的锥形束 CT（CBCT）数据。使用 Mimics 21.0 重建 TMJ 3D 模型。在 3D 模型上直接测量 14 项测量指标，如前、上、后关节间隙，并进行比较。
成人安氏Ⅱ类 2 分类错牙合患者治疗后髁突的形状和位置发生变化。固定矫治器和透明矫治器治疗后，前关节间隙减小，后关节间隙增大，髁突向前移至关节窝中心。透明矫治器治疗后关节上间隙和关节窝深度增加，而固定矫治器治疗后无明显变化。
安氏Ⅱ类 2 分类错牙合患者治疗后髁突形状和位置变化明显，表明髁突在治疗过程中发生适应性重建。这些结果为正畸临床的诊断、治疗计划设计和治疗监测提供了参考。
