Purpose: To determine the prevalence of oral-maxillofacial trauma among Brazilian victims of physical aggression and identify its associated factors from a medico-legal and forensic perspective. Materials and Methods: A cross-sectional study was carried out involving the analysis of complete medico-legal and social reports of 3668 victims of physical aggression treated at a centre of legal medicine and forensic dentistry over the course of four years. The dependent variable was the occurrence of oral-maxillofacial trauma. The independent variables were sociodemographic status and characteristics of physical aggression. Statistical analyses included the chi-squared test (p 0.05) as well as univariate and multivariate logistic regression analyses. Results: Oral-maxillofacial trauma occurred in 1655 cases (45.1%). Individuals who lived in suburban areas (OR = 1.32; 95%CI = 1.11-1.58) and those who were victims of community violence (OR = 1.20; 95%CI = 1.03-1.40) perpetrated by someone known to them (OR = 1.24; 95%CI = 1.03-1.40) using physical force (OR = 2.31; 95%CI = 1.96-2.72) on weekends (OR = 1.19; 95%CI = 1.04-1.37) and during nighttime hours (OR = 1.23; 95%CI = 1.08-1.41) were more likely to exhibit oral-maxillofacial trauma. Conclusion: The prevalence of oral-maxillofacial trauma was high and the associated factors were area of residence, type of violence, type of offender, mechanism of violence, day, and period of occurrence. Keywords: forensic sciences, maxillofacial injuries, violence