The Influence of Mandibular Gonial Angle on Fracture Site

The mandibular angle is influenced by multiple codependent morphologic dynamic factors, such as osseous anatomy, forces exerted by the muscles of mastication, occlusal loading patterns, and anatomic structures. These factors can influence the presence of a fracture in this area. Our research aimed to investigate a potential correlation between the risk of angle fractures and age, gender, fracture etiology, gonial angle size, presence of mandibular third molars, or presence of occlusal support.

This retrospective cohort study was composed of patients treated for mandibular fractures between 2007 and 2018. The primary predictor variable was the gonial angle, and the primary outcome variable was the fracture site. Other study variables included demographic data, fracture etiology, third molar status, and presence of occlusal support. Appropriate univariate, bivariate, and multivariate statistics were applied, and statistical significance was set at P < .05.

Of 332 isolated mandibular fractures included, 109 were angle fractures; 165, condylar; and 58, body or symphysis. The mean age of patients with angle fractures was 25.5 years, compared with 31.3 years and 32.7 years for those with condylar fractures and body or symphysis fractures, respectively. The mean gonial angle was 125.4° in patients with angle fractures compared with 120.9° and 120.2° in those with condylar fractures and body or symphysis fractures, respectively. The variables that were found predictive of angle fractures were a wider gonial angle and the presence of third molars.

Third molars and the gonial angle are predictors of the location of mandibular fractures. Wide gonial angles and the presence of third molars are predictors of mandibular angle fractures.