Evaluation of bone height of the free fibula flap in mandible reconstruction.

Abstract

Use of a vascularized free fibula flap has become a preferred method of mandible reconstruction after oncologic surgical ablation. Despite its many advantages, the low vertical height of the graft is a potential drawback and severe long-term atrophy of fibular bones may cause stress fracture and is disadvantageous for osseointegrated dental implants and facial contours. Therefore, it is important to investigate the degree of resorption based on the fibular height and the factors related to resorption over time. The influence of aspects of the intraoperative surgical procedure, such as preservation of a nutrient artery from the peroneal artery to the fibula bone marrow and the number of segmental osteotomies, has not been examined previously. Therefore, the purpose of this study was to examine the change in fibular height and the factors influencing resorption, including those associated with the surgical procedure. A retrospective analysis was performed in 19 patients who underwent free vascularized fibular mandibular reconstruction for oncologic surgical defects without radiotherapy. Postoperative Panorex examinations were used to evaluate fibular height, and 7 factors with a potential influence on long-term fibular height were evaluated: age, gender, length of the mandible defect, number of segmental osteotomies, preservation of a direct nutrient artery from the peroneal artery to the fibula bone marrow, length of follow-up, and delayed placement of osseointegrated dental implants. Fibular bone height decreased in 13 patients (68%), was unchanged in 2 (11%), and increased in 4 (21%). Segmental osteotomies and female gender were significant factors promoting fibular bone resorption (P < 0.001 and P < 0.001, respectively), and preservation of a nutrient artery to the bone marrow, male gender, and delayed placement of osseointegrated dental implants were significant factors inhibiting bone resorption (P < 0.01, P < 0.001, and P < 0.05, respectively). Age, length of follow-up period, and length of the mandibular defect showed no significant relationship with bone resorption (P = 0.77, P = 0.78, and P = 0.105, respectively). The results of this study showed that fibular height in mandibular reconstruction can be maintained by preservation of a direct nutrient artery to bone marrow, avoidance of osteotomies, and delayed placement of osseointegrated dental implants, all of which inhibit fibular bone resorption.