Revision 3 for 'Temporomandibular joint trauma'

The TMJ can be affected by trauma in a number of ways:

• Condylar process fractures
• TMJ dislocation
• Fracture of the mandibular fossa

Condylar process fractures

The condylar process of the mandible is involved in around 30% of mandibular fractures. 

Classification

Classification of condylar fractures is (as for other fractures) by location and displacement.

Location

Fractures are either through the condylar neck or through the head.

• Head
  • Intracapsular
  • Extracapsular (similar to high neck fracture)
• Neck
  • High (similar to extracapsular head fracture)
  • Mid
  • Low

Displacement

Fractures can be either displaced or non-displaced. When displacement is present it is most frequently medial (i.e. direction of condyle relative to ramus) due to the action of the lateral pterygoid muscle. 

Additionally, and important in deciding treatment, is the degree of contraction (in verticle plane)

Imaging

Traditionally OPGs and plain films have been the main stay of imaging, although facial CT is increasingly being used. The role of MRI in the acute setting is unclear, but is likely to become more prevalent if and when early intervention on disc and capsule injury is shown to be beneficial.

Treatment

• Conservative
• Closed reduction
  • +/- intermaxillary fixation
  • +/- splints
• Open reduction

TMJ dislocation

content pending - please feel free to contribute.

Fracture of the mandibular fossa

content pending - please feel free to contribute.