An investigation into the relationship between mandibular third molars and angle fractures in Nigerians.

We examined the relationship between the presence or absence of mandibular third molars and angle fractures in Nigerians between January 1976 and July 1997. Information was obtained from patients' case records and radiographs.A total of 490 patients were seen during the study period, 408 of whom (83%) had their third molars present, and 76 of whom had angle fractures. Road traffic accidents (n =304, 62%) were the main cause of the fractures. Of these, 44 (14%) had angle fractures compared with 14/75 (19%) patients in whom the mechanism of injury was a fight or assault.Sixty-five of the 408 patients whose third molars were present (16%) had angle fractures, as did 11/82 (13%) who did not have third molars (p =0.57). Of the 77 patients whose lower third molars were not erupted, 24 (31%) had angle fractures compared with 52/331 (16%) in whom the lower third molars were erupted (p =0.002). These findings suggest that angle fractures are uncommon in this population because of their particular mechanism of injury. In addition, the presence of a lower third molar does not necessarily predispose to fractures of the angle of the mandible. However, angle fractures are more likely to occur in people with unerupted lower third molars than in those in whom they have erupted.