Trauma X-ray - Axial skeleton
Mandible

Key points

  • Whenever one fracture is seen - check for a second fracture or dislocation at the temporomandibular joint

Mandible fractures

The mandible can be considered as an anatomical ring of bone, stabilised at each end at the temporomandibular joints. A break of the ring in one place will usually be accompanied by further break in the ring elsewhere. If you see one fracture, look for a second fracture, or a dislocation of the temporomandibular joint.

Standard views

Orthopantomogram (OPG) and Mandible views.

Both views are necessary because fractures are often only seen on one image. The OPG is a panoramic view acquired with the camera panning around the patient.

Normal mandible - Orthopantomogram (OPG)

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Normal mandible - Orthopantomogram (OPG)

  • Follow the cortical edge all the way around the mandible
  • Check the temporomandibular joints
  • Asterisks = Inferior alveolar canal - the course of the inferior alveolar nerve

Normal temporomandibular joint - OPG (detail)

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OPG detail - Normal temporomandibular joint

  • The condyle of the mandible meets the glenoid fossa of the temporal bone to form the temporomandibular joint (TMJ)

Normal mandible - Mandibular view

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Normal mandible - Mandibular view

  • Follow the cortical edge all the way around the mandible

Mandible fracture - OPG

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Mandible fracture - OPG

  • (Same patient as image below)
  • A fracture of the left mandible body is easy to see
  • On the right the cortical outline is difficult to follow at the base of the condyle (?) - but no second fracture is readily seen

Mandible fracture - Mandibular view

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Mandible fracture - Mandibular view

  • (Same patient as image above)
  • On this view the right condylar fracture is more easily seen