目的：探讨锥形束CT(cone-beam computed tomography，CBCT)融合三维面像用于研究牙颌面畸形患者正颌术后软硬组织变化的可行性，并应用此方法初步测量各软硬组织标志点手术前后的位置变化。 方法： 选取10例牙颌面畸形患者，分别于术前（T0）和术后3个月（T1）拍摄大视野CBCT和三维面像。利用MIMICS和Geomagic Studio软件对图像进行处理分析，将CBCT进行阈值分割并与三维面像融合，生成新的三维立体模型，探讨该方法可行性。使用3D 色谱分析（3D color map）和测量平均距离对CBCT与三维面像配准过程的误差进行定性和定量分析。通过CBCT骨组织配准，将新生成的手术前后三维模型置于同一空间坐标系，测量各标志点［鼻尖点( pronasale, Prn )、鼻下点（subnasale, Sn）、上唇突点（labrale superior, Ls）、前鼻棘点（anterior nasal spine, ANS）、上齿槽座点（subspinale, A）、上中切牙点（upper incisor edge, UIE）］手术前后位置变化。结果： CBCT融合三维面像用于研究正颌术后软硬组织变化具有可行性，配准误差在0.3 mm以内，通过3D 色谱分析直观看到，面部区域配准良好。正颌术后唇部各标志点（Ls、ANS、A、UIE）位置差异有统计学意义(P<0.05)，而鼻部标志点（Prn、Sn）位置差异无统计学意义(P>0.1)。结论：CBCT融合三维面像作为一种新方法可以用于临床研究正颌术后软硬组织变化，具有较高的精确度和可重复性。正颌术后唇部软硬组织标志点位置明显变化，而鼻部标志点位置受正颌手术影响较小。

Objective： To evaluate the feasibility of integrating 3D photos and cone-beam computed tomography (CBCT) images and to assess the degree of error that may occur during the above process, and to analyze soft and hard tissue changes after orthognathic surgery using this new method. Methods: Ten patients with maxillofacial deformities were chosen. For each patient, CBCT scans and stereophotographic images were taken before and 3 months after surgery. 3D photos were superimposed onto the CBCT skin images using relatively immobile areas of the face as a reference. 3D color maps and mean distances were used to evaluate the errors that might occur during the process. Two reference planes were set up using certain points. The distances between Prn (pronasale)，Sn (subnasale)，Ls (labrale superior)，ANS (anterior nasal spine)，A (subspinale)，UIE (upper incisor edge) to the coronal plane were calculated before and after surgery. In order to verify the repeatability of this method, we examined the distances twice at two-week intervals. Paired t test was used to evaluate the reproducibility. Results: CBCT and 3D photos could be successfully fused with clinically acceptable errors. This new method could be used to evaluate soft and hard tissue changes after orthognathic surgery. The 3D color maps showed that the two images could be fused with minimal errors. The mean distances were within 0.3 mm, and the locations of landmarks on maxilla and mandible such as Ls, ANS, A, UIE changed significantly after orthognathic surgery (P<0.05).Landmarks on the nose such as Prn，Sn had little changes after surgery (P>0.1). The paired t test showed that the mean value and standard deviation were （0.08±0.98） mm. Conclusion: Fusing of CBCT and 3D stereophotographic images used as a new method in evaluating soft and hard tissue changes after orthognathic surgery was feasible and accurate. The virtual 3D composite craniofacial models permitted concurrent assessment of hard and soft tissues during diagnosis and treatment planning. Maxillary and mandibular locations had significant association with orthoganthic surgery while the nasal tissue was not simp affected by surgery.