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Plain Films - Mandible

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  • AP with baseline at 90 deg and central ray 15 deg caudally
  • Right & Left oblique mandibles
  • Slit Townes to show condyles

Trauma mandible

If patient unable to move head you still need both obliques, a lateral and AP or PA


  • Patient supine
  • Place cassette in holder beside patient's head as for lat skull
  • Horizontal ray, tube angled about 30 deg cranially (cephalically, to head)
  • Centre : about 2cm below angle of jaw on side closest to tube
  • Shoulder must be well down out of the way or, if patient can move head you can tilt head slightly toward film 5-10 deg

Alternative oblique method: (if patient able to move)

  • Roll patient 45 deg from supine to affected side
  • Head in lateral position, raise chin slightly
  • Tube: 30deg cranial angulation
  • Exposure: equivalent to lateral exposure


  • Horizontal ray as for lat skull to include symphysis menti (chin)

TMJ (supine)

  • Patient prone
  • Head lateral
  • Angle caudally 15 deg
  • Centre to TMJ closest to film eg 2cm above and 2cm behind EAM on side facing up
  • Cone tightly. Make two exposures - one with mouth open, one mouth closed

Or  if patient is old/co-operative  enough:OPG/Cone beam CT  (ACH L2 emergency dept) 

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Document Control

  • Date last published: 28 October 2017
  • Document type: Imaging Protocol
  • Services responsible: Paediatric Radiology

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