Evaluation of the Precision and Accuracy of Computer-Guided Implant Surgery: A Prospective Clinical Study Comparing .STL Files from the Intraoral Rehabilitation Scanning with the Digital Project

Objectives: This prospective cohort study aimed to evaluate the accuracy and precision of static computer-guided, flapless implant surgery in partially edentulous patients, comparing the virtually planned and clinically achieved implant positions. Materials and Methods: From 2017 to 2022, 40 patients (20 males and 20 females) received a total of 129 implants across 59 partial rehabilitations, with 62 implants placed in the maxilla and 67 in the mandible. All interventions were performed by a single experienced operator using dental-supported stereolithographic guides and a flapless protocol. The discrepancy between planned and actual implant positions was measured using reverse engineering software, assessing linear deviations at the implant Platform (coronal) and apex, as well as angular deviations. Subgroup analyses were conducted based on the jaw (maxilla vs. mandible) and the type of surgical guide support (Kennedy classes I–IV). Results: The mean linear deviation was 1.16 ± 0.58 mm at the apex and 0.80 ± 0.41 mm at the implant Platform (coronal). The mean angular deviation was 3.23° ± 1.86°. Slightly higher deviations were observed in the mandible than in the maxilla. Group-wise analysis showed minor variations depending on the type of guide support. Conclusions: Static computer-guided surgery demonstrated measurable linear and angular deviations between planned and achieved implant positions. These discrepancies should be considered during treatment planning, especially in narrow ridges or Class I configurations.