Leonardo Ciocca*; Achille Tarsitano; Riccardo Mattoli; Cristiana Breccia; Pietro Felice; Lorenzo Breschi

Department of Biomedical and Neuromotor Science, University of Bologna, Bologna, Italy

Background: Restoring the correct anatomy and occlusion of the mandible after cancer ablative surgery is a challenge, but modern CAD-CAM techniques enable customized new bone plates to position the fibula-free flap (FFF) as related to the occlusion and prosthetic gingival/crown ratio.

Aim/Hypothesis: The present prospective clinical study aimed to describe the workflow of prosthetically guided mandibular reconstruction, and the results are verified in a case series.

Material and Methods: Fourteen consecutive patients (mean age 36.1; range: 16–61 years) affected by benign and low-grade malignant diseases involving the mandible were selected. All patients underwent surgical resection and mandibular reconstruction with the microvascular FFF using a double-level customized titanium bone plate. The FFF positioned at the level of the alveolar bone allowed for restoration of the correct gingival/crown ratio. Six months after surgery, the oral implants were positioned with static/dynamic navigation, and the prosthetic rehabilitation was completed 6 months later. The positions of the FFF segments were isolated by overlapping their planned digital design with the postoperative computed tomography data. Rotation angles, translation vectors, and total error were investigated to determine the exact deviation for the planned position of the FFF. Occlusal and aesthetic results of the prosthetic rehabilitation were also evaluated.

Results: Analyzing the average mean distance as an absolute value, the surface deviation between the preoperative fibular cranial segment (FCSplan) and the postoperative FCSpost-op was 1.04 mm, while the average signed distance was −0.28 mm. Patients underwent implant surgery and were rehabilitated with a partial fixed prosthesis. One patient developed a major complication during follow-up (bony flap necrosis). All implant positions and the relative prosthetic rehabilitation respected the initial planning. The aesthetic profile of the lower third of the face was preserved.

Conclusion and Clinical implications: The height discrepancy between the FFF and the native mandible was challenging in the present clinical study, as we proposed a new prosthetically guided protocol to reconstruct the mandible. The double-level bone plate allowed for restoration of the correct prosthetic gingival/crown ratio, the aesthetic face profile, and native occlusion. The digital projection provided a high level of accuracy during reconstructive surgery of the mandible with the FFF.

Disclosure of Interest: None Declared.

Keywords: bone graft, CAD/CAM, clinical studies/trials