The Facial Bones

Learning outcomes
  • Assess skeletal radiographs using a systematic approach
  • Use common lines which are helpful in interpreting the image
  • Understand the different radiographic projections and how the anatomy changes with position
  • Describe facial anatomy
  • Understand mechanisms of injury and the likely fractures which may result
  • Search for subtle injuries and understand their clinical significance
  • Recognise potential soft tissue injuries
Facial Bones Projections

Occipito-mental View

  • The PA occipito-mental view provides excellent demonstration of the upper and middle thirds of the face including the orbital margins, frontal sinuses, zygomatic arches and maxillary antra:

Normal facial bones

Occipito-mental 30 View

  • With 30 degrees of caudal angulation, the orbits are demonstrated less well. However, the zygomatic arches and the walls of the maxillary antra are seen clearly:

Normal facial bones
Three lines for inspecting the OM views
Normal lines   Normal lines
Line 1:
  • Look for widening of the zygomatico-frontal sutures
  • Fractures of the superior rim of the orbits
  • "Black-Eyebrow" sign due to orbital emphysema
  • Opacification / air-fluid level in the frontal sinuses

Line 2:
  • Look for fractures of the superior aspect of the zygomatic arch
  • Fractures of the inferior rim of the orbits
  • Soft tissue shadow in the superior maxillary antrum
  • Fractures of the nasoethmoid bones and medial orbits

Line 3:
  • Look for fractures of the inferior aspect of the zygomatic arch
  • Fractures of the lateral maxillary antrum
  • Opacification / air-fluid level in the maxillary sinuses
  • Fractures of the alveolar ridge
Compare the injured side with the uninjured side.

Fractures of the Facial Skeleton
Fractures of the Orbits
Blowout fracture - left
Orbital emphysema - right   Orbital emphysema - right
Fractures of the Zygoma
Tripod fracture - left   Tripod fracture - left
Zygomatic arch fracture - left
Fractures of the Maxilla
Mandibular Projections
Orthopantomogram (OPG)
  • This is an excellent method of demonstrating virtually all mandibular fractures, including the coronoid and condylar processes. Be aware however; occasionally symphysis menti fractures may not be seen.
Normal OPG

Posteroanterior (PA) Mandible
  • The OPG must be supplemented with a PA mandible to establish displacement of fractures. This will demonstrate the body and symphysis menti, and also provide tangential views of the rami and the necks of the condyles:
Normal PA mandible
Lateral obliques
  • In the absence of an OPG, the lateral obliques will demonstrate the body and ramus on each side. The articulation at the temporomandibular joint may also be assessed:
Normal lateral oblique - paediatric   Normal lateral oblique - paediatric
Anatomy of the mandible
Mandibular anatomy   Mandibular anatomy
Fractures of the mandible
Coronoid process
Symphysis menti
Alveolar ridge

Fracture right angle and left body
Bilateral condyle fractures
Fracture right body, left coronoid and ramus   Fracture right body, left coronoid and ramus

- return to top -