Accuracy and the role of experience in dynamic computer guided dental implant surgery: An in-vitro study

Abstract

Background: The development of new imaging technologies like Cone-Beam Computer Tomography (CBCT) has allowed a great advance in the pre-surgical implant planning. Computer Assisted Surgery (CAS) in implantology has been described aiming to minimize the differences between the preoperative planning and the final treatment outcome. The dynamic CAS, also known as surgical navigation system, allows to determine the real position of the surgical drill on the reconstructed 3D image of the CBCT. It guides the surgeon, while performing the surgical procedure, to the preoperative planned position. Aim: To assess the accuracy and the role of the surgeon’s experience comparing the implant placement using both freehand and a dynamic navigation system. Materials and methods: A randomized in-vitro study was made. Six resin mandible models and 36 implants were used. Two investigators with different degrees of clinical experience placed implants using either the CAS Navident® system (Navident group) or the conventional freehand method (freehand group). Accuracy assessment was measured by overlapping the virtual presurgical placement of the implant in a CBCT and the real position in the postoperative CBCT. Descriptive and bivariate analysis of the data was made. Results: The Navident group had a significantly higher accuracy for all studied variables, except for the 3D entry and depth deviation. This system significantly enhanced the accuracy of the unexperienced professional in several outcome variables in comparison with the freehand implant placement method. On the other hand, when the implants were placed by the experienced clinician, the Navident® system only allowed to improve the angulation deviation. If both degrees of experiences are compared, significant differences were only found when the freehand method was employed. The implants placed with the Navident® system had similar deviations. Conclusion: The dynamic computer assisted surgery system Navident® allows a more accurate implant placement in comparison with the conventional freehand method, regardless of the surgeon’s experience. However, this system seems to offer important advantages to unexperienced professionals, since they can significantly reduce their deviations, achieving the same results of experienced clinicians.