目的：评价下颌后缩畸形患者正颌外科术后髁突形态的三维变化。方法：回顾2011年1月至2013年1月于北京大学口腔医院颌面外科接受手术的下颌后缩畸形患者18例，基于术前及术后1年双侧颞下颌关节锥形束CT（cone-beam computed tomography，CBCT）数据进行髁突三维分割及重建，并将术前和术后1年的髁突影像进行配准，通过三维色谱分析评价髁突形态的三维变化。应用SPSS 13.0统计软件对获得数据进行统计学分析。结果：术前与术后1年髁突表面平均距离的均方根为（0.37±0.11） mm，差异具有统计学意义（P<0.05）。髁突表面骨改建的分布差异具有统计学意义（P<0.05），骨吸收主要发生在髁突后斜面，骨沉积主要发生在前斜面。结论：基于CBCT数据的三维影像重叠法表明，下颌后缩畸形患者正颌外科术后髁突形态发生了改建。

Objective： To evaluate the effect of orthognathic surgery on condylar morphology changes by comparing three-dimension surface reconstructions of condyles using cone-beam computed tomography (CBCT) data. Methods: In the study, 18 patients with mandible retrognathism deformities were included and CBCT data of 36 temporomandibular joints were collected before surgery and 12 months after surgery. Condyles were reconstructed and superimposed pre-and post-operatively to compare the changes of condylar surfaces. One-sample t test and χ² test were performed for the analysis of three-dimension metric measurement and condylar head remodeling signs. P＜0.05 was considered significant. Results: The root-mean-square (RMS) of condylar surface changes before and after the surgery was (0.37±0.11) mm, which was significant statistically (P<0.05). The distribution of condylar remodeling signs showed significant difference (P<0.05). Bone resorption occurred predominantly in the posterior area of condylar head and bone formation occurred mainly in the anterior area. Conclusion: Three-dimension superimposition method based on CBCT data showed that condylar morphology had undergone remodeling after mandibular advancement.