An In Vitro Model to Evaluate the Accuracy of Guided Implant Placement Based on the Surgeon's Experience

Purpose: To evaluate whether there are differences in the accuracy of guided implant placement based on the surgeon's experience level. Materials and Methods: Fifteen surgeons, divided into three groups based on experience level (group I, expert; group II, intermediate; group III, novice), placed six implants in five identical mandibles (75 mandibles and 450 implants). A planning and stereolithographic guide was generated using cone beam computed tomography (CBCT) images and implant planning software (Nemoscan, Nemotec) and was used in all cases. After the implants were placed in each mandible, another scan was taken, and the three-dimensional (3D) images of each scan were blended with the images in the planning guide to evaluate any deviations. Any differences in platform and apex position and the angle of the implant were measured. The differences between each surgeon and each group were compared using multivariate analysis of variance (MANOVA). Results: There were significant differences in the implant angles among the three groups (P = .001). Group III (novices) presented the greatest angle deviation and showed more deviations than group I (experts) (P = .024) and group II (intermediate) (P = .001) did. There were no significant differences between groups I and II (P = .368). There were no significant differences among the groups in terms of platform (P = .135) and apex position (P = .092). Conclusion: Some degree of deviation can occur between the planned placement of the implant and its definitive placement, and this deviation may be influenced by the surgeon's experience. Expert surgeons show less angle deviation than novice surgeons. Although these differences (less than 0.5 degrees) are statistically significant, they may be considered clinically irrelevant. Keywords: computer-assisted, dental implants, guided surgery, implant placement accuracy, stereolithographic surgical guide