Department of Prosthodontics, University Hospital Erlangen, Erlangen, Germany.
J Craniomaxillofac Surg. 2010 Sep;38(6):436-40. doi: 10.1016/j.jcms.2009.10.025. Epub 2009 Nov 24.
The present study describes a new method of evaluating the precision of surgically placed dental implants compared after virtual planning of implant positions using cone-beam computed tomography (CT) data and surgical guide templates. This method reduces radiation exposure for patients participating in scientific studies.
Twenty-three implants in 10 patients with a unilateral free-end gap in the mandible (Kennedy Class II) were evaluated. After three-dimensional planning of implant position, the implant bed was prepared with a surgical guide template and transmucosal drilling. Preoperative cone-beam CT images were matched with postoperative images of the master cast with implant replicas. Deviations between planned and achieved positions were measured in position and axis.
On average, the match between planned and placed implant axis was within 4.2 degrees (range, 0.0-10.0). The mean difference in distance at the implant shoulder was 0.9 mm (range, 0.0-4.5). The mean difference in distance at the implant apex was 0.6mm (range, 0.0-2.7) in the lateral/medial direction and 0.9 mm (range, 0.0-3.4) in the anterior/posterior direction.
This alternative matching method provides reliable postoperative evaluation of differences in position and axis of planned and placed implants while reducing patient radiation exposure.
本研究描述了一种新的方法，用于评估使用锥形束 CT（CBCT）数据和外科导板模板对种植体位置进行虚拟规划后，手术植入的种植体的精度。这种方法降低了参与科学研究的患者的辐射暴露。
评估了 10 名单侧下颌游离端间隙（Kennedy Ⅱ类）患者的 23 个种植体。在进行三维种植体位置规划后，使用外科导板模板和黏膜下钻孔制备种植床。将术前的 CBCT 图像与带有种植体复制件的主模型的术后图像进行匹配。测量计划位置和实际植入位置之间的偏差。
平均而言，计划植入体轴与实际植入体轴的匹配度在 4.2 度以内（范围 0.0-10.0）。种植体肩部距离的平均差值为 0.9mm（范围 0.0-4.5）。种植体根尖在侧向/内侧方向的平均差值为 0.6mm（范围 0.0-2.7），在前侧/后侧方向的平均差值为 0.9mm（范围 0.0-3.4）。
这种替代的匹配方法在降低患者辐射暴露的同时，为评估计划种植体位置和植入体轴之间的差异提供了可靠的术后评估。
