Microsurgical reconstruction of the mandible part II: new classification system and algorithm

Abstract

Background: Various classifications of mandibular defects have been attempted, but no universally accepted system exists. After 25 years of experience, the senior author idealized a new mandibulectomy classification which could give a more detailed anatomical description leading to a more precise algorithm for reconstruction. Methods: A new classification of mandibular defects is proposed: class I (anterior arch), class II (body), class III (ascending ramus), class IV (hemimandibulectomy), and class V (extended mandibulectomy). Each class is further subdivided into those that preserve or resect intra- and/or extraoral soft tissues (ABCD). This classification takes in account four factors that need to be thought when planning mandibular reconstruction: location/specificity of the defect, osteotomies, and bone and soft tissue requirements. Results: A total of 218 defects were classified according to this new classification. Nearly 40% of the cases were classified as a class I defect followed by class IV (36,7%), class II (16%), class V (6,8%), and class III (0,5%). The authors also created an algorithm for reconstruction. In cases of an “only-bone” defect, the free iliac crest flap is the preferable choice, especially in class I and IV. When intra- or extraoral soft tissue is needed (types B and C), the fibula flap is our choice of excellence. In cases of extensive defects (type D), the fibula flap and the sequentially linked flow through flap are the preferred options. Conclusions: Optimizing mandibular defect classification with better integration of data-driven information along with clinicopathological evidences and related experience allows for better clinical judgment and choices. We believe that our new classification system and algorithm for reconstruction can be a valuable guiding tool for dealing with complex mandibular reconstruction. Level of evidence:: Level III, therapeutic study