Comparison of the accuracy of pilot-drill-guided and fully guided implant surgery with dynamic navigation. In vitro model study

The aims of the present study are to measure and compare dental implant deviations with fully guided and pilot-drill-guided protocols using dynamic navigation systems in polyurethane models. The pilot-drill-guided group was determined to be the study group and included 12 implant applications. In this group, the pilot hole was drilled with navigation guidance, and the procedure was completed freehandedly. In the control group, all the drilling and implant placement steps were performed using the navigation system, and a total of 12 implants were placed. The pre- and postoperative images were compared to calculate the magnitude of implant deviation. The quantitative data of the two groups were compared using the independent-samples t-test and Mann-Whitney U-test. The analyses revealed that the length of the procedure significantly differed between the two groups (p < 0.001). The procedure duration was significantly shorter in the study group. The entry deviation values of the two groups were not significantly different (p = 0.079). The analysis revealed the apex deviation to be higher in the study group than in the control group (p = 0.003). However, the two-dimensional vertical apex deviation values of the implants were not significantly different between groups (p = 0.068). Angular deviation was determined to be significantly higher in the study group (p < 0.001). In the present study, all implants were successfully placed in the models using a dynamic navigation system. The results of this study may be useful for future clinical studies.

Real-Time Image-Guided Navigation in the Management of Alveolar Cleft Repair

Objectives: To present the use of dynamic navigation system in the repair of alveolar cleft. Patients and Participants: A total of three non-syndromic patients with unilateral alveolar cleft were involved in this study. Real-time computer-aided navigation were used to achieve restoration and reconstruction with standardized surgical technique. Methods: With the individual virtual 3-dimensional (3-D) modeling based on computed tomography (CT) data, preoperative planning and surgical simulation were carried out with the navigation system. During preoperative virtual planning, the defect volume or the quantity of graft is directly assessed at the surgical region. With the use of this system, the gingival periosteum flap incision can be tracked in real-time, and the bone graft can be navigated under the guidance of the 3-D views until it matches the preoperatively planned position. Results: Three patients with alveolar cleft were successfully performed under navigation guidance. Through the model alignment procedure, accurate matches between the actual intraoperative position and the CT images were achieved within the systematic error of 0.3 mm. The grafted bone was implanted according to the preoperative plan with the aid of instrument- and probe-based navigation. All the patients were healed well without serious complications. Conclusions: These findings suggest that image-guided surgical navigation, including preoperative planning, surgical simulation, postoperative assessment, and computer-assisted navigation was feasible and yielded good clinical outcomes. Clinical relevance: This dynamic navigation could be proved to be a valuable option for this complicated surgical procedure in the management of alveolar cleft repair.

Retraction: Setoguchi et al. Accuracy Assessment of Implant Placement in a Newly Developed Dynamic Navigation System: A Pilot Study. Appl. Sci. 2021, 11, 6593

The published article [...]

Mandibular Reconstruction With Fibula Flap and Dental Implants Through Virtual Surgical Planning and Three Different Techniques: Double-Barrel Flap, Implant Dynamic Navigation and CAD/CAM Mesh With Iliac Crest Graft

IntroductionVertical discrepancy between the fibula flap and the native mandible results in difficult prosthetic rehabilitation. The aim of this study was to evaluate the outcomes of 3D reconstruction of the mandible in oncologic patients using three different techniques through virtual surgical planning (VSP), cutting guides, customized titanium mesh and plates with CAD/CAM technology, STL models and intraoperative dynamic navigation for implant placement. Material and methodsMaterial and MethodsThree different techniques for mandibular reconstruction and implant rehabilitation were performed in 14 oncologic patients. Five patients (36%) underwent VSP, cutting guides, STL models and a customized double-barrel titanium plate with a double-barrel flap and immediate implants. In six patients (43%), VSP, STL models and a custom-made titanium mesh (CAD/CAM) for 3D reconstruction with iliac crest graft over a fibula flap with deferred dental implants were performed. Three patients (21%) underwent VSP with cutting guides and customized titanium plates for mandibular reconstruction and implant rehabilitation using intraoperative dynamic navigation was accomplished. Vertical bone reconstruction, peri-implant bone resorption, implant success rate, effects of radiotherapy in vertical reconstruction, bone resorption and implant failure, mastication, aesthetic result and dysphagia were evaluated.ResultsSignificant differences in bone growth between the double-barrel technique and iliac crest graft with titanium mesh technique were found (p<0.002). Regarding bone resorption, there were no significant differences between the techniques (p=0.11). 60 implants were placed with an osseointegration rate of 91.49%. Five implants were lost during the osseointegration period (8%). Peri-implant bone resorption was measured with a mean of 1.27 mm. There was no significant difference between the vertical gain technique used and implant survival (p>0.385). Implant survival rates were higher in non-irradiated patients (p<0.017). All patients were rehabilitated with a fixed implant-supported prosthesis reporting a regular diet (80%), normal swallowing (85.7%) and excellent aesthetic results.ConclusionsMulti-stage implementation of VSP, STL models and cutting guides, CAD/CAM technology, customized plates and in-house dynamic implant navigation for mandibular defects increases bone-to-bone contact, resolves vertical discrepancy and improves operative efficiency with reduced complication rates and minimal bone resorption. It provides accurate reconstruction that optimizes implant placement, thereby improving facial symmetry, aesthetics and function.