- Is the
panoramic radiography intraoral, extraoral or something else?
Panoramic radiography is an extraoral radiographic technique that is used
to examine maxilla and mandible.
parts move and which are stationary when using panoramic technique?
Both the tube head and the film rotate around the patient who is stationary.
X-ray tube goes in one direction, while the film in the opposite.
- How do
exposure times with panoramic technique compare with those such as periapical
radiography using paralleling technique?
Exposure time in
panoramic radiographic units is fixed and cannot be changed, while in intraoral
radiography it can be changed.
three uses for panoramic radiography?
1. To evaluate impacted teeth
2. To evaluate eruption patterns, growth and development
3. To detect diseases, lesions and conditions of jaws
- How useful
are panoramic radiographs for evaluation of caries?
Now quite useful. Pan is not recommended for evaluation and diagnosis of
does the word “tomo” mean?
Tomo is a Greek
word that means section.
term describes the three dimensional curved zone in which structures are
clearly demonstrated on a panoramic radiograph?
The focal through,
also known as the image layer.
- How is
panoramic tube head collimator different than ordinary intraoral collimator?
used in the intraoral x-ray units is lead plate with a small round or rectangular
opening in the middle, whereas the collimator used in the panoramic units
is lead plate with an opening in the shape of a narrow vertical slit.
kind of film is used in panoramic radiography?
Screen film is
used in panoramic radiography. It is available in two sizes: 5x12 inch and
- Why is
a thyroid collar not recommended during panoramic radiography?
Because it blocks
part of the beam and obscures important diagnostic information.
is the imaginary plane that passes through the top of the ear canal through
the bottom of the eye socket called?
special instructions are given the patient to be followed during actual
exposure using the panoramic unit?
- To elevate the
tongue so it touches the palate and keep the tongue in that position during
- to close the lips around the bite-block
is a ghost image?
A ghost image is
radiopaque artifact seen on a panoramic film that is produced when a radiodense
object is penetrated twice by the x-ray beam.
causes lead apron artifacts on panoramic images?
lead apron, or lead apron with thyroid collar.
radiograph effect occurs when the patient’s chin is tipped up during panoramic
- reverse smile
- hard palate is superimposed over the maxillary roots
- maxillary incisors appear blurred and magnified
causes an “exaggerated smile” on panoramic radiographs?
Frankfort plane downward (chin tipped down).
some advantages of using panoramic radiography technique?
1. Field size
3. Patient cooperation
4. Minimal exposure
some disadvantages of using panoramic radiography technique?
1. Image quality
2. Focal trough limitations
4. Equipment cost.