Retrospective Analysis of the Correlation Between Mandibular Gonial Angle and Incidence of Mandibular Angle Fracture-A Radiomorphometric Study

Purpose The aim of this study was to analyse the association between mandibular gonial angle and the risk of mandibular angle fracture in North Indian population. Materials & Methods A retrospective study was conducted on digital panoramic radiographs of 80 patients with isolated mandibular fractures. The patients were categorized into mandibular angle and non-angle fracture groups. The primary predictor variable was the presence or absence of a high gonial angle, while the primary outcome variable was angle fracture. Secondary predictors were the presence of third molar and mandibular height. Other study variables included demographic data and fracture displacement. The mandibular gonial angle and mandibular height were measured using the MicroDicom DICOM viewer. Data obtained was analysed using statistical software S.P.S.S. version 23.0 (IBM Inc.) Results Mean gonial angle of patients in the angle fracture group was 127.85 +/- 6.90 degrees which was 5.22 degrees more than the non-angle group (mean = 122.63 +/- 6.55 degrees, p = 0.001). Patients with high gonial angles were also statistically associated with an 11.76 times increased chance for angle fracture (Adjusted odds ratio 11.76, 95% confidence interval 3.95-35.05, p < 0.001) when compared with subjects without high gonial angles. The data also demonstrated that there was a reduction in mean mandibular height with increase in gonial angle (P = - .609). Also the relationship between the presence of impacted third molar and mandibular angle fracture was statistically significant (p < 0.001). Conclusion Individuals with high gonial angle, shorter mandibular height and impacted mandibular third molars are at an increased risk for mandibular angle fractures.