Clinical and radiological analysis of osteochondromas of the mandible using cone-beam computed tomography

Osteochondroma (OC) is rare in the mandibular condyle. The radiographic appearance of this lesion is diverse. Most radiologists and surgeons agree that helical computed tomography (CT) has great diagnostic potential for OC. Cone-beam CT (CBCT) can also afford three-dimensional information, and it is widely used to evaluate oral and maxillofacial diseases. The purpose of this study was to elucidate the CBCT characteristics of OC in the mandible and increase the radiographic knowledge of mandibular OC. The CBCT radiographs of 31 cases of mandibular OC (29 cases in the condyle and two cases in the coronoid process) were reviewed. All data were obtained from the oral radiology department of our institution from 2009 to 2014. The final diagnoses of all cases were based on pathological examination. Patient age, sex, symptoms, and radiographic findings were considered in all cases. Percentages, the t test, and the chi (2) test were used for statistical analyses. Progressive facial asymmetry, malocclusion, and opening deviation were the most common symptoms. There was no sex-related difference in age at onset, symptoms, or tumor location. Although the mandibular OCs exhibited diverse shapes, they could be divided into two types: bony outgrowth (more common) and condylar expansion. The structures adjacent to the mandibular OC were often affected by the tumor; cortical hyperostosis of the affected glenoid fossa was found in most cases. Mandibular OCs may show different growth positions encircling the condyle and exhibit varying shapes. CBCT can provide enough information for use in the diagnosis of OCs.