Active participation in sports is a risk factor for maxillofacial fractures. The aim of this retrospective multicentre study was to survey and evaluate the characteristics of mandibular fractures, and dental injuries that occurred during the practice of baseball and softball in Sendai, Japan. The records of 454 patients with maxillofacial fractures from three departments of Oral and Maxillofacial Surgery across a period 14 years were analysed. Fifty-one patients with 56 mandible fractures and dental injuries that occurred playing baseball or softball were included in this multicenter retrospective study. Patients were divided according to age, gender, sites of fractures, mechanism of fractures and treatment methods. There were 42 males and nine females, with a male-to-female ratio of 4.7:1.0. The mean age was 19.9 years old (range: 13-47 years old). As for the site, body of the mandible fractures prevailed, followed by the condyle, symphysis and angle. Fractures were mostly caused by the impact of a ball (42; 82.4%), followed by collisions with another player (5; 9.8%) and direct strike of a bat (4; 7.8%). All patients with mandibular fractures were treated with open reduction and internal fixation, except for six patients with condylar head fractures who were managed conservatively. The impact of a thrown ball against the batter's mandible can cause a condylar fracture when playing baseball and softball. © 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.