Fibrous union of the mandible: a review of 27 patients

To identify personal data, social traits, fracture characteristics, and treatment modalities that result in the development of mandibular fibrous union.

Hospital charts and radiographs for 714 patients with mandibular fractures treated between March 1984 and August 1993 were retrospectively reviewed for the presence of fibrous union. The charts were evaluated for age, sex, race, fracture etiology, fracture location, personal habits, medical compromise, compliance, type and timing of treatment, type and timing of antibiotics, the presence of infection, type of fibrous union, and definitive care. The data were recorded and analyzed.

A 3.2% incidence of fibrous union was identified. The body of the mandible was the most frequent site of fibrous union (66%). Twenty-one of the 24 patients surgically treated had a tooth in the line of fracture. Only five had teeth removed at the time of the initial procedure. Thirteen developed a post-operative infection. Ninety-four percent of the patients with fibrous union had at least one medical or social risk factor, which included alcohol abuse (63%), intravenous drug abuse (26%), noncompliance (37%), pulmonary problems (37%), smoking (41%), and others (37%).

Age, race, sex, mechanism of injury, and failure to use antibiotics were not factors in the development of fibrous union. Medical and social risk factors (especially self-abusive habits), inadequate immobilization, anatomic location, teeth in the line of fracture, and the occurrence of late postsurgical infections were factors that contributed to the development of fibrous union.