Published online by Cambridge University Press: 05 July 2015
‘This is an OM/OPG/PA view x-ray of the face/mandible.’
• Occipitomental (OM) view at 0°: frontal sinuses, orbits, maxillary antra, nasal bones and ethmoid air cells
• Occipitomental (OM) view at 30°: additional features – zygoma, mandible, infraorbital foramina, odontoid peg
• Orthopantomogram (OPG): mandible, maxilla, teeth, TMJ and inferior alveolar canal
• PA mandible: mandibular fractures
• Frontal bones and sinuses
• Orbits and orbital floor
• Maxilla: medial and lateral walls of maxillary antra
• Zygomatic arch
• Mandible: symphysis, body, angle, ramus, condyle and coronoid process
• Temporomandibular joint (TMJ)
Circles: broken circle indicates a possible fracture
• Frontal sinuses
• Maxillary sinuses
• Nasal and ethmoid spaces
Lines: broken line indicates a possible fracture
• Lines of Dolan (OM30)
• McGrigor's lines
• Elephant trunks of Rogers (zygomatic arch fractures): formed from lines of Dolan
• Maxillary fractures: alveolar process; lateral and medial walls of maxillary antra.
• Zygomatic arch fracture: look at ‘elephant trunks’.
• Tripod fractures: zygoma detachment (complex zygomaticomaxillary fracture). Suture lines involved are: 1. zygomaticofrontal suture; 2. orbital floor; 3. infraorbital rim; 4. lateral wall of maxillary sinus.
• Inferior orbital margin fracture.
• Orbital floor ‘blow-out’ fracture.
• ‘black eyebrow’ sign: surgical emphysema in the upper orbital rim area
• ‘teardrop sign’: herniation of orbital soft tissues in the maxillary antrum
• fluid level in antrum of maxilla
• Mandibular fractures.
• Bone: lytic lesions and cysts
• Soft tissues: contour changes
• Sinusitis (OPG and OM): opacity of maxillary and frontal sinuses
• Osteomyelitis (OPG and OM): opacity of mandible and maxilla
• TMJ (OPG).
• Fractures and caries.
To complete the examination…
• If suspecting a complex fracture or inadequate views, ask for CT face/skull to determine.
• Facial trauma is associated with C-spine and head injuries, so consider CT head and C-spine imaging.