A review on the classification of mandibulectomy defects and suggested criteria for a universal description

Several mandibular defect classifications after oncological resection have been proposed with no universal acceptance among surgeons and prosthodontists. Established criteria for describing these mandibulectomy defects are lacking.

The purpose of this systematic review was to analyze the classification systems of mandibular defects available in the scientific literature, provide a critical appraisal, and identify the criteria necessary for a universal description of mandibular discontinuity defects.

An electronic search of the English language literature between 1971 and 2020 was performed on 2 electronic databases (PubMed and Cochrane Library). The search was conducted using MeSH terms and free text words: Mandible neoplasm AND Mandibular reconstruction OR Mandible resection OR Mandible defect AND classification, followed by the application of inclusion and exclusion criteria. Studies describing the classification of osteoradionecrosis of the mandible, mandibular fracture, impacted mandibular third molar, and mandibular endodontic or periodontal treatment were not included. The full texts of selected articles were reviewed in depth to provide a critical appraisal. The various descriptive factors of each classification system were tabulated to identify criteria suitable for the universal description of mandibular discontinuity defects.

The electronic search yielded a total of 239 titles and abstracts. Of these, 52 titles relevant to the review were identified by the 2 reviewers independently. Those studies that did not match the predetermined inclusion criteria and duplicates were excluded. By reviewing the 21 selected studies and applying exclusion criteria, 12 studies were selected for full-text reading. A manual search in the references of the selected publications was performed, which yielded 1 additional article that satisfied the inclusion criteria. Thus, a total of 13 full-text articles were included in the final review. After further qualitative analysis and tabulation of relevant information from selected classification systems, the 8 descriptive criteria and a pyramidal hierarchical chart were proposed that included the extent of bony defect, soft tissue defect, dental status, mandibular function, neurological status, condyle status, type of reconstruction, and combined resection.

The spectrum of patients with mandibulectomy defects following resection varies greatly. The question of the most ideal classification system remains unresolved. Eight different criteria for the description of mandibular discontinuity defects and the pyramidal hierarchical chart proposed will allow surgeons and prosthodontists to better communicate and conceptualize an individualized surgical and prosthetic treatment plan.