Surgical Navigation in Mandibular Reconstruction: Accuracy Evaluation of an Innovative Protocol

Abstract

Aim: the purpose of this work is to present an innovative protocol for virtual planning and surgical navigation in post-oncological mandibular reconstruction through fibula free flap. In order to analyze its applicability, an evaluation of accuracy for the surgical protocol has been performed. Methods: 21 patients surgically treated for mandibular neoplasm have been included in the analysis. The Brainlab Vector Vision 3.0® software for surgical navigation has been used for preoperative surgical planning and intra-operative navigation. A post-operative accuracy evaluation has been performed matching the position of mandibular landmarks between pre-operative and post-operative CT scans. Results: the maximal discrepancy observed was included between −3.4 mm and +3.2 mm, assuming negative values for under correction and positive values for overcorrection. An average grade of accuracy included between 0.06 ± 0.58 mm and 0.43 ± 0.68 mm has been observed for every mandibular landmark examined, except for mandibular angles that showed a mean discrepancy value included between 1.36 ± 1.73 mm and 1.46 ± 1.02 mm when compared to preoperative measurements. Conclusion: a satisfying level of accuracy has been observed in the protocol presented, which appears to be more versatile if compared to closed custom-made systems. The technique described may represent a valid option for selected patients, but it cannot be considered for routine activity because of the complexity of the method, the mobility of the jaw, the necessity of surgical navigator and the long surgical learning curve that is required.

15 Years Experience in Surgical Navigation with Tracked Instruments

“…All the procedures were successfully performed, with no reported complications among the patients. Navigation accuracy measured was: <0.5 mm in 40.47% (17) of cases, <1 mm in 45.23% (19) of cases and <1.5 mm in 14.28% (6) of cases. The recorded mean accuracy was < 0.87 mm, with a standard deviation of 0.5 mm.…”

“…Hirch et al ( 2009) and observed that real-time guidance offered by surgical navigation in mandibular reconstruction with vascularized fibula flap reduces the margin of error compared to free-hand techniques, decreases surgery duration, and demonstrates high accuracy and applicability [14][15][16]. Sozzi et al (2022) describe in their protocol how the positions of the screw holes for the reconstruction plate are prerecorded on a 3D model of the patient's jaw. Subsequently, before performing the resection, the screw holes are realized using a recorded drill, whose bit position can be tracked in real-time on CT images to ensure precise placement of the screws as per the planned location.…”

“…Subsequently, before performing the resection, the screw holes are realized using a recorded drill, whose bit position can be tracked in real-time on CT images to ensure precise placement of the screws as per the planned location. Nevertheless, they noted that this method requires a substantial amount of pre-surgical setup time and a steep learning curve for the surgeon [17].…”

The Use of Dynamic Navigation Systems as a Component of Digital Dentistry

“…Surgical DNS in mandibular reconstruction is considered challenging for practitioners because of the constant mandibular movement that affects precise synchronization of the data set with the navigation system. Sozzi et al (2022) created a dental splint using radiopaque fiducial marker points for surgical navigation. The position between the splint and mandible remained unchanged during the phases of computed tomography (CT) image acquisition and surgery, ensuring a precise match between the patient and radiological data.…”

Computer-Aided Dynamics Intraoperative Navigation in Oral Medicine: A Review

“…Postoperative imaging and examination showed that the new mandible was well positioned with good occlusion in all cases, and facial symmetry was achieved in all cases with an unrestricted opening. Sozzi et al (2022) proposed an innovative protocol for virtual planning and surgical navigation in post-oncological mandibular reconstruction through a bula free ap and evaluated the accuracy of the surgical protocol. The location of mandibular markers was evaluated for postoperative accuracy in the preoperative and postoperative CT scans of 21 patients who underwent surgical treatment for mandibular tumors.…”