To analyze the mandibular fractures which presented over a 3-year period at an emergency hospital in Belo Horizonte, Brazil. The data collected included age, sex, aetiology, date of trauma, associated maxillofacial trauma, anatomic site of fracture, and treatment. The analysis involved descriptive statistics and the Pearson's chi-square, Bonferroni, Kolmogorov-Smirnov, Kruskal-Wallis and Mann-Whiney tests, and analysis of variance. There were 1,454 mandibular fractures in 1,023 patients. Males of 20-29 years of age sustained the majority of fractures. Traffic accidents were the major causes of trauma, followed by violence and falls. A high incidence of fractures in women due to violence was observed. The condyle region was found to be the most common fracture site in the mandible. A surgical approach was performed in most cases. There were more accidents causing mandibular fractures on the weekends. The individuals with mandibular fractures due to "traffic accidents" were younger than those due to "violence" and "falls". There was a significant statistical association between age and aetiology as well as between sex and aetiology of mandibular fractures. Copyright © 2011 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.