Mandibular reconstruction with the fibula flap-Postoperative remaining function and the aim of reconstruction-

The aim of functional mandibular reconstruction is to maintain remaining function and to obtain new functions such as by using a dental implant. We have to predict the postoperative function to clarify the aim of reconstruction. This paper evaluates the remaining function of patients who underwent various degrees of mandibulotomy and examines suitable methods to reconstruct them.<BR>This study investigated (1) postoperative occlusal pressure of remaining molars and postoperative diet in patients who received mandibular reconstruction with fibula flap; (2) influence of postoperative function on plate fracture; (3) position of osteotomy of fibula for dental implant; (4) postoperative bone resorption and factors that influence it. The importance of soft tissue graft for contour reconstruction is also mentioned.<BR>Forty-eight patients who received mandibular reconstruction with fibula flap and who were followed up for more than 6 months were examined. As for postoperative diet, it was more strongly affected by the number of remaining teeth than masticatory muscles. Although the patients who had all of the ipsilateral masticatory muscles removed lost their occlusal force conspicuously (39% against normal), if their occlusion stayed about half they could produce an occlusal force of 200N, enabling them to eat an approximately conventional meal. If such patients are reconstructed with reconstruction plate and soft tissue flap, it is highly likely that the reconstruction plate will break. The case in which the mandible was removed to the contralateral canine (or mental tubercle) needed one osteotomy of fibula at the site of the ipsilateral canine for anterior mandible reconstruction. In the case in which the contralateral mental foramen was removed, two osteotomies at the site of both canines were necessary. Annual resorption of fibula was less than 0.2 mm in cases with an occlusal force exceeding 300N, but some factors potentiated bone atrophy. Soft tissue reconstruction in extensive mandibular defects has great significance for functional and aesthetic results. As for the fibula flap, it is required to graft other flap.