Rinaldi Marco, Ganz Scott D
Private Practice, Bologna, Italy.
Private Practice, Fort Lee, New Jersey.
Compend Contin Educ Dent. 2019 Mar;40(3):e1-e4.
This study introduces a novel protocol for the placement of zygomatic implants utilizing presurgical planning with 3-dimensional (3D) computed tomography (CT)/cone-beam (CB)CT diagnostic technologies and advanced 3D printing through the development of a specific surgical guide.
The protocol relied on large field of view CT/CBCT for an accurate assessment of the maxillary arch to plan zygomatic implant receptor sites. CT/CBCT-derived surgical guides of a novel design were then fabricated using 3D printing technology. An exact replica of the entire maxilla and zygomatic bone was then fabricated in actual scale model size to allow for a simulation of the operation using replicas of implants to be used during the surgical intervention. Guidance was also provided for the sinus fenestration as part of the surgical template. Four patients received a total of 10 zygomatic implants all placed by the same surgeon.
Preoperative positions of the zygomatic implants were compared with the postoperative implant positions by merging the pre- and postoperative CT scan datasets. The degree of accuracy of the superimposition was measured utilizing sophisticated software. Apical, coronal, and angular deviations were determined for each implant. Deviations from the computerized project to the actual implant positions ranged from 2 mm to 3 mm with angular deviations ranging between 1.88 and 4.55 degrees.
Placement of zygomatic implants requires surgical experience due to close proximity of vital anatomical structures. This study used methods of superimposition that illustrated satisfactory correspondence between inserted implants and the virtual plan. No adjacent vital anatomical structures were damaged. The novel surgical guide design afforded the surgeon visual control of the drilling protocol. Positioning the guide in close proximity to the entry point of the zygomatic body aided control of the drills up to the vicinity of the exit point, significantly limiting problems associated with angular deviation. Reducing errors and complications is essential for zygomatic implants to remain a viable treatment alternative, and further research on a guided approach to their placement is encouraged.
本研究引入了一种新型的颧骨种植体植入方案，该方案利用三维（3D）计算机断层扫描（CT）/锥束（CB）CT诊断技术进行术前规划，并通过开发特定的手术导板实现先进的3D打印。
该方案依靠大视野CT/CBCT精确评估上颌牙弓，以规划颧骨种植体植入位点。然后使用3D打印技术制作新型设计的CT/CBCT衍生手术导板。接着按实际比例模型尺寸制作整个上颌骨和颧骨的精确复制品，以便使用手术干预时要植入的种植体复制品模拟手术。作为手术模板的一部分，还为鼻窦开窗提供了引导。4名患者共植入10枚颧骨种植体，均由同一位外科医生操作。
通过合并术前和术后CT扫描数据集，比较颧骨种植体的术前位置和术后位置。利用精密软件测量叠加的精确程度。确定每个种植体的根尖、冠状和角度偏差。从计算机规划到实际种植体位置的偏差范围为2毫米至3毫米，角度偏差在1.88度至4.55度之间。
由于重要解剖结构距离很近，颧骨种植体的植入需要手术经验。本研究采用的叠加方法表明植入的种植体与虚拟规划之间具有令人满意的对应关系。没有相邻的重要解剖结构受损。新型手术导板设计使外科医生能够直观地控制钻孔操作流程。将导板放置在靠近颧骨体入口点的位置有助于控制钻头直至出口点附近，显著减少与角度偏差相关的问题。减少误差和并发症对于颧骨种植体成为可行的治疗选择至关重要，鼓励进一步研究其植入的引导方法。
