Mandible fracture

February 8, 2013

CT, Face, Facial, Trauma

We’ve all seen it…the dude that had two beers after church and got jumped by a couple guys while he was minding his own business.

Mandible fx 1Mandible fx 2Mandible fx 3Mandible fx 4

This Facial CT demonstrates several comminuted fracture lines through the mandible.  CT imaging is highly sensitive and specific for mandible fractures and is the imaging-of-choice in most emergency departments.  Plain films can also be obtained but subtle fractures can be missed; the extent and characterization of the fractures is much better identified on CT.

Its always difficult in the minor facial trauma to know when to pull the trigger and order a CT of the face…especially in the current environment of questioning CT utilization.  Some clinical exam findings that would increase your suspicion of mandibular fracture include (1):

1.  The patient having subjective feeling that their “teeth don’t fit.”

2.  Malocclusion.

3.  Anesthesia of the upper lip or chin (mental nerve distribution).

4.  Pain or tenderness near the anterior ear, especially with mandibular range-of-motion.  This is concerning for mandibular condyle fracture but also could represent TMJ strain, sprain, or dislocation.

An obvious deformity, laceration of the gingival area (indicating an open fracture), or severe mechanism are high concerns for mandibular fracture and CT imaging should be considered.  The “tongue blade test” (have the patient bite down on a tongue blade with their molars on both sides.  Negative test if the patient is able to break the tongue blade) has a 95% sensitivity in excluding injury in a patient with mild jaw pain and no obvious injury or instability (1).

Author:  Russell Jones, MD


1.  Bailitz J.  Trauma to the Face.  In:  Tintinalli JE, Stapczynski JS, et al.  Tintinalli’s Emergency Medicine:  A Comprehensive Study Guide.  7ed.

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  1. The LITFL Review 094 - Life in the Fast Lane medical education blog - October 2, 2013

    […] Mandible fracture – a nice guide to reading facial CT scans. […]

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