Trauma Flashcards
Facial buttress system
- Frontal bone
- Sphenoid bone
- Zygomatic bone
- Maxillary bone
Vertical buttress
* Nasomaxillary
* Zygomaticomaxillary
* Pterygomaxillary
* Vertical mandible
Horizontal buttress
* Frontal bar
* Inferiro orbital rim
* Hard palate
When to do imaging of the face
When the patient is clinically stable (airway, breathing, circulation)
For cervical spine clearance
Identify any brain injuries (Glasgow Coma Scale)
Post traumatic seizures
Suspected open skull fracture
Signs of fracture at skull base (panda eyes, cerebospinal fluid leakage from ears and nose, Battle’s sign)
Plain film radiography
Plain film is a 2D image of a 3D object
Facial series
Water’s view (PA view with angulation)
Caldwell view (PA view)
Towne’s view
Lateral view
Base view
Mandible series
Orthopanthogram
Oblique view
PA mandible
Towne’s view
The most consistently helpful view in facial trauma is
**The Waters view
**
It tends to show all of the major facial structures at least as well and often
better than other radiographic views of the face
Water’s view (occipitomental view)
Chin
Chin touches the image receptor with the head tilted forming an angle of 37 degrees with the canthomeatal line
Helpful in viewing Maxillar, Maxillary sinus, Zygoma, Zygomatic arch, Oribtal rims and nasal floor
McGrigor & Campbell lines
Line 1- Supraorbital
Line 2- Infraorbital
Line 3- Maxillary sinus
Line 4- Occlusal plane
Line 5- Lower body of the mandible
Caldwell view (Posterior-Anterior view)
Occipito-frontal view
Nose
Canthomeatal line forms a 10 degree angle with the horizontal plane and the Frankfort plane is perpendicular to the image receptor
Orbit and ethmoid sinuses can be viewed
Towne’s view
Occiput
Canthomeatal line is perpendicular to the film
Posterolateral wall of Maxillary sinus and Zygomatic arch
Submentovertex view
(Jug handle view)
Beam is directed below the mandible to the vertex of the skull so it is 2 cm anterior to the condyle
Useful for viewing zygomatic arches
Lateral Oblique
Coronoid process
**Mandible **
Head tilted, Image receptor is placed on patient’s cheek of interest around the premolar-molar area so that the image receptor (cassette) is 2 cm below the inferior border of the mandible
Indications:
Mandibular body , angle , ramus condyle ,coronoid
fractures
Ramus
Patient head is tilted such that the angle of the opposite side and the condyle of the side that needs to be viewed are in the same plane. Image receptor is placed over the ramus and the beam is directed 2 cm below the angle
Reverse Towne’s
forehead, open mouth
Canthomeatal line form an agle of 30 degrees with the image receptor
Condylar fractures
five key structures that must be
evaluated in radiographic evaluation of plain films
Zygoma
Orbits
Nasal structures
Paranasal sinus
Mandible
Three types of Lefort fractures
These fractures involve separation of all or a
portion of the maxilla from the skull base
*** LeFort I fracture **(transmaxillary fracture)
Fractures pass through the inferior
portions of the medial and lateral maxillary buttresses
only one that involves the anterolateral margin of the nasal fossa just above the maxillary alveolar process
* LeFort II fracture
Le Fort II fracture involves fractures through the
zygomaticomaxillary and frontomaxillary sutures
only one that involves the inferior orbital rim
* LeFort III fracture
Le Fort II fracture involves fractures through the
zygomaticomaxillary and frontomaxillary sutures. The Le Fort II fracture is the only one that involves
the inferior orbital rim and the zygomatic arch
Imaging recommendation for mandibular fractures
Plain film mandible series (PA, lateral, Towne’s and bilateral oblique)
Panoramic radiography (orthopantogram)
CT
Panoramic film
Impacted teeth and its relation with the mandibular canal
To evaluate eruption patterns
To detect diseases, lesions, conditions of the jaws and the extent of large lesions
To evaluate trauma
Retained teeth or root tips in edentulous patients
Post-operative examination and patient education
Implants
CENTER OF ROTATION
The pivotal point or axis around which the cassette
carrier and X-ray tubehead rotate, is termed a ROTATION CENTER
Focal trough
The focal trough (also known as the Image layer) is defined as a 3-D curved zone in which structures are clearly demonstrated on a panoramic radiograph
DRAWBACKS OF EXTRA ORAL
TECHNIQUES
Magnification occurs due to the greater object
to film distance used.
Details are not well defined.
Contrast is reduced as the secondary
radiation produced by the soft tissues is
more.
It is a 2- D image of 3- D structure.
