3D手术设计辅助面部偏颌畸形治疗

Application of 3D surgical design in the treatment of facial deformities

目的探讨3D手术设计辅助面部偏颌畸形的治疗效果及改进方向。方法将患者全头颅CT数据以DICOM格式输入mimics及ProP lan CMF软件,进行头颅3D重建、牙列配准替换、标准头位校准、手术标志点3D坐标测量、虚拟截骨手术,根据手术标志点的3D坐标进行颌骨3D空间移动,通过对上下颌骨上下、左右、前后的平移及冠状面侧滚(Yaw)、矢状面俯仰(Pitch)、水平面偏转(Roll)的旋转,摆正面部中线、平面,纠正咬关系,重建咬。通过镜像观察,协调面部轮廓,精确计算术中去骨量及范围。通过3D打印手术导板,将术前3D手术设计转移至手术现实。术后拍摄全头颅CT,通过术前设计和术后CT配准,检测误差。结果在实际手术中,3D手术导板与牙列贴合良好,通过合板确定颌骨移动位置,术后CT与术前手术设计颌骨重合度高,检测误差无统计学意义,但面形预测与术后实际面形有一定出入。结论 3D手术设计辅助偏颌畸形治疗数字化流程的应用,使术前颌骨畸形的纠正得到最大化和可视化,缩短了手术时间,提高了手术精度,是未来面部骨骼畸形治疗的必然方向。

Objective To explore the efficacy and direction of improvement of 3D surgical design in the treatment of facial micro-maxillary slant deformity. Methods All cranial CT data of patients was entered into Mimics and ProP lan CMF software in DICOM format. Three-dimensional reconstruction of skull, registration and replacement of dentition, calibration of standard head position, 3D coordinate measurement of surgical landmark and virtual osteotomy were performed. Three-dimensional spatial movement of the jaw was performed based on the 3D coordinates of surgical landmarks. Through the upper and lower, left and right, anterior and posterior translation of the supermaxilla and mandible, coronal plane roll（Yaw）, sagittal roll pitch（Pitch）, and the rotation of horizontal deflection（Roll）, the facial midline and（occlusal） plane was straightened, the（occlusion） relationship was corrected and reconstructed. Mirror observation was conducted to coordinate the facial contour and calculate the amount and scope of bone loss during the surgery. The operation guide plate was printed through 3D technology and the preoperative 3D surgical design was transferred to the operative practice. Whole cranial CT scan was taken postoperatively. Errors were detected by CT registration pre-and postoperative. Results In the actual operation, the 3D surgical guide fit well with the dentition. The moving position of the jaw was identified through a plywood model. High coincidence of the jaw bone existed between the preoperative surgical design and the postoperative CT, and no statistically significant errors were detected. There was a certain discrepancy between the prediction and reality of the facial contour. Conclusion The application of 3D surgical design can maximize and visualize the correction of deformities of the micro-maxillaria. It can shorten operation time and enhance operation accuracy. We predict this method as a future direction for treatment of facial skeletal deformities.