Department of Second Dental Center, Ninth People's Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Department of Oral Implantology, Ninth People's Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Int J Oral Maxillofac Surg. 2021 Jan;50(1):116-120. doi: 10.1016/j.ijom.2020.03.018. Epub 2020 Jun 2.
Zygomatic implants (ZIs) are used for the oral rehabilitation of patients with maxillectomy defects as an alternative to extensive bone grafting surgeries. New technologies such as computer-assisted navigation systems can improve the accuracy and safety of ZI placement. The intraoral anchorage of fiducial markers necessary for navigation registration is not possible in the case of a severe maxillary defect and lack of residual bone. This technical note presents a novel extraoral registration method for a dynamic navigation system guiding ZI placement in patients with maxillectomy defects. Titanium microscrews were inserted in the mastoid process, supraorbital ridge, and posterior zygomatic arch as registration markers. The mean fiducial registration error (FRE) was 0.53 ± 0.20 and the deviations between the planned and placed ZIs were 1.56 ± 0.54 mm (entry point), 1.87 ± 0.63 mm (exit point), and 2.52 ± 0.84° (angulation). The study results indicate that the placement of fiducial markers at extraoral sites can be used as a registration technique to overcome anatomical limitations in patients after maxillectomy, with a clinically acceptable registration accuracy.
颧骨种植体（ZIs）用于上颌骨缺损患者的口腔修复，作为广泛骨移植手术的替代方法。计算机辅助导航系统等新技术可以提高 ZI 放置的准确性和安全性。在严重上颌骨缺损和缺乏残余骨的情况下，导航注册所需的口腔内基准标记的内固定锚不能实现。本技术说明介绍了一种新的用于引导上颌骨缺损患者 ZI 放置的动态导航系统的外部注册方法。钛微螺钉被插入乳突、眶上嵴和后颧骨作为注册标记。平均基准标记注册误差（FRE）为 0.53±0.20，计划和放置的 ZI 之间的偏差为 1.56±0.54mm（进入点）、1.87±0.63mm（出口点）和 2.52±0.84°（角度）。研究结果表明，在外部位点放置基准标记可作为一种注册技术，用于克服上颌骨切除术后患者的解剖限制，具有可接受的临床注册准确性。
