Do mandibular third molars alter the risk of angle fracture?

PURPOSE: In this study, we measured the relationship between the presence of mandibular third molars (M3s) and angle fractures. In addition, the study examined the relationship between M3 impaction level and angle fracture susceptibility. PATIENTS AND METHODS: We used a multicenter retrospective cohort study design and a sample composed of patients treated for mandibular fractures. The predictor variables were 1) the presence of an M3 and 2) the position of an M3 classified according to the Pell and Gregory system. The outcome variable was the presence or absence of an angle fracture. RESULTS: The study sample was composed of 1,210 patients. Patients with M3s present had a 2.1 times greater chance of an angle fracture than did patients without M3s (P <.001). There was a statistically significant variation in the risk for an angle fracture depending on M3 position (P <.001). CONCLUSIONS: In patients who sustain a mandible fracture, the presence of M3s significantly increases the likelihood of an angle fracture. In addition, the risk for an angle fracture depends on M3 position.