The significance of radiographic follow-up of mandibular fractures

ABSTRACT

For many years, healing membranous bone fractures have been known to show a persistent lucency at the fracture interface. Radiographic follow-up has proven to be of little value as a guideline for healing of mandibular fractures. Recently, a fracture has been treated by rigid internal fixation by metallic plate and screws rather than closed reduction and wire fixation, we expected that some difference in the radiographic features of fracture healing. To investigate these questions we undertook a retrospective radiographic and clinical analysis of 33 followed patients with fractures of the body and angle of the mandible from 1993 to 1997. There were 26 male and 7 female patients ranging in age between 5 and 74 years, with an average of 29.7 years. All patients were managed by open reduction with metallic plates and screws. The length of follow-up ranged from 9 to 187 weeks. Total 81 radiographic follow-up films were obtained and divided into 3 grades according to the degree of radiolucency of fracture lines; grade 0 radiolucent fracture line and no evidence of fracture interface calcification, grade 1 decreased radiolucent area and evidence of fracture interface calcification, and grade 2 disappearance of fracture line.Until follow-up of 8 weeks, all of the radiographs showed grade 0. From 8 weeks to 16 weeks, 62.5 percent showed grade 0 and 37.5 percent showed grade 1. From 16 weeks to 48 weeks, 38.5 percent showed grade 1 and 61.5 percent showed grade 2. After follow-up of 48 weeks, all showed grade 2.In this study we have shown that the radiographic disappearance of mandibular fracture lines was usually accomplished by 48 weeks. We feel that radiographic union of the mandible is lagging well behind clinical union, but disapperance of the fracture line in rigidly fixated mandibular fracture was occurred earlier than healed by fibrous union. We propose that radiographic union of the mandible by approximately 1 year can be a guideline for the normal mandibular bone healing.