The effect of a blast on the mandible and teeth: transverse fractures and their management.

Transverse mandibular fractures caused by blast waves have given us a better understanding of the physical and pathophysiological effects on this anatomical region. The external contour of the mandible, being rounded in parts (en face) and flat in others (lateral) will experience different effects of the blast. Impact of a spherical blast wave will inflict transverse lines of fractures on the mandibular body, and may be associated with transverse shearing of teeth at the cementoenamel junction. Fractures of the mandible caused by blast are different from those in the same region caused by any type of civilian trauma; these are the vertical to the longitudinal axis unlike comminuted fractures caused by shrapnel or bullet injuries. Fractures of the mandibular body by blasts are single or multiple parallel fractures in the lower border, between the apices of the roots and the mandibular lower border. Fractures are broken off by acceleration or deceleration of the blast wave.