Bobek Sam, Farrell Brian, Choi Chris, Farrell Bart, Weimer Katie, Tucker Myron
Surgeon, Swedish Medical Center, Seattle, WA.
Fellowship Director, Carolinas Center for Oral & Facial Surgery, Charlotte, NC.
J Oral Maxillofac Surg. 2015 Jun;73(6):1143-58. doi: 10.1016/j.joms.2014.12.008. Epub 2014 Dec 13.
We describe an alternative workup protocol for virtual surgical planning of orthognathic surgery using an intraoral fiducial marker, clinical photography, and the digital transfer of occlusal data. We also discuss our initial experience using this protocol in a series of patients.
A retrospective cohort study was performed of consecutive patients who had undergone combined maxillary and mandibular osteotomies for the correction of dentofacial deformities at 1 center. These patients underwent treatment planning using the modified virtual surgical planning protocol described in the present report. The primary outcome evaluated was the accuracy of the method, which was determined through superimposition of the surgical plan to the postoperative cone-beam computed tomography (CBCT) scan. The secondary outcomes included the accuracy of the natural head position readings and the adequacy of the CBCT scanned stone models for the fabrication of occlusal splints.
The population included 25 patients. The root mean standard deviation (RMSD) from the preoperative plan to the postoperative scan at the maxillary cephalometric points was 1.2, 1.4, and 2.1 mm in the axial, sagittal, and coronal planes, respectively. The RMSD of the superimposed plan to the postoperative scan at the 3 mandibular cephalometric points was 1.2, 0.8, and 0.7 mm in the axial, sagittal, and coronal planes, respectively. The average variance from the axial, sagittal, and coronal planes for the natural head position was 0.05, 2.22, and 0.69 mm, respectively. All splints fabricated from the CBCT occlusal data fit the stone models and were used intraoperatively. In the subset of patients whose models were both digitally transferred and laser scanned, the superimposition of the laser scan data to the CBCT scanned data was found to have a maximum variation of 0.2 mm at the occlusal level.
The use of an intraoral fiducial marker changed the workflow for the data collection needed for virtual surgical planning of the correction of dentofacial deformities, while still obtaining accurate results. Because the device does not cause lip distortion, the possibility of virtually predicting a more expectant postoperative lip position exists without the need for additional scans. Furthermore, this work flow allows the transfer of data to be isolated to digital media.
我们描述了一种用于正颌外科虚拟手术规划的替代检查方案，该方案使用口内基准标记、临床摄影以及咬合数据的数字传输。我们还讨论了在一系列患者中使用该方案的初步经验。
对在1个中心接受上颌和下颌联合截骨术以矫正牙颌面畸形的连续患者进行了一项回顾性队列研究。这些患者使用本报告中描述的改良虚拟手术规划方案进行治疗规划。评估的主要结果是该方法的准确性，通过将手术计划与术后锥形束计算机断层扫描（CBCT）进行叠加来确定。次要结果包括自然头位读数的准确性以及用于制作咬合夹板的CBCT扫描石膏模型的充足性。
该人群包括25名患者。在上颌头影测量点，从术前计划到术后扫描在轴向、矢状和冠状平面的均方根标准差（RMSD）分别为1.2、1.4和2.1毫米。在下颌3个头影测量点，叠加计划与术后扫描在轴向、矢状和冠状平面的RMSD分别为1.2、0.8和0.7毫米。自然头位在轴向、矢状和冠状平面的平均方差分别为0.05、2.22和0.69毫米。所有根据CBCT咬合数据制作的夹板都与石膏模型适配并在术中使用。在模型既进行了数字传输又进行了激光扫描的患者亚组中，发现激光扫描数据与CBCT扫描数据在咬合水平的最大差异为0.2毫米。
使用口内基准标记改变了牙颌面畸形矫正虚拟手术规划所需数据收集的工作流程，同时仍能获得准确结果。由于该设备不会导致唇部变形，因此无需额外扫描就有可能虚拟预测出更理想的术后唇部位置。此外，这种工作流程允许将数据传输隔离到数字媒体。
