The document identifies common errors that can occur when taking panoramic dental x-rays. These include the teeth being positioned too far anterior or posterior to the focal trough, the patient's head being turned or tipped in various directions, issues with the placement of the lead apron, and other errors like patient movement, double exposures, or using incorrect exposure settings. Proper patient positioning and technique are necessary to avoid these errors and ensure diagnostic quality panoramic dental x-rays.

1. Panoramic Technique Errors
The following slides identify common panoramic
technique errors.

2. Teeth Too Anterior
If the teeth are positioned in front of the notches in the
bitestick (see diagram below left), the anterior teeth
will appear narrower and will be blurred (less sharp
than normal). If the teeth are in front of the notches,
they are closer to the film, resulting in less
magnification horizontally (narrowing). Being out of
the focal trough makes the images less sharp.

3. Teeth Too Anterior
This film shows the blurring and narrowing of
the anterior teeth.
R L

4. Teeth Too Anterior
R L
R L

5. Teeth Too Posterior
If the teeth are positioned behind the notches in the
bitestick (see diagram below left), the anterior teeth
will appear wider and will be blurred (less sharp than
normal). If the teeth are behind the notches, they are
farther from the film, resulting in more magnification
horizontally (widening). Being out of the focal trough
makes the images less sharp.

6. Teeth Too Posterior
R L

7. Teeth Too Posterior
R L

8. Head Turned
If the head is turned slightly to the side (not
centered on the bitestick), the structures on
one side will be closer to the film and the
structures on the other side will be farther
from the film. In the diagram below, the head
was turned to the right and the teeth are
closer to the film on that side.

9. Head Turned
The teeth are smaller on the side to which the
head is turned. (When the teeth are closer to the
film, there is less magnification horizontally).
The teeth that are farther from the film are wider
because there is increased magnification
horizontally.

10. Head Turned
In this patient, the molars on the patient’s right side
are noticeably wider than the molars on the
patient’s left. Which way was the head turned?
To the left. Left side closer to film, less magnification.
R L

11. Head Turned
On this film, not only are the teeth wider on one side,
but the ramus is also wider on that side. (The black
arrows are the same length on both sides). Which side
was farthest from the film?
The patient’s right side; farther from the film, more
magnification.
R L

12. Head Turned
In this film, the patient’s head was turned to the
right, resulting in a widening of the teeth and
ramus on the patient’s left side.
R

13. Head Tipped Down
If the head is positioned so that the Frankfort Plane
is inclined downward (see diagram below left), the
mandibular incisors will appear shortened and the
mandible will be V-shaped (Exaggerated smile).

14. Head Tipped Down
Notice how short the mandibular incisors appear.
The rest of the teeth are relatively normal.
R L

15. Head Tipped Down
Again we see shortened mandibular incisors, V-
shaped mandible.
R

16. Head Tipped Up
If the Frankfort Plane is angled upward, the mandible
will be “squared-off” (angle of the mandible
approximately 90 degrees) and the hard palate will be
superimposed over the roots of the maxillary teeth.
May have the appearance of a “reverse” smile.

17. Head Tipped Up
In the film below, the hard palate (red arrows) is
covering the roots of the maxillary teeth. Note
the reverse smile.
R L

18. Head Tipped Up
This film shows the reverse smile and it is
difficult to see the root areas of the maxillary
teeth.

19. Lead Apron
If the lead apron is improperly positioned so that it
is located high on the back of the patient’s neck, it
may block part of the beam and result in a clear
(appears white on the viewbox) area on the film.
Lead apron shadow

20. Lead Apron
The two completely radiopaque areas on the film
below were caused by the lead apron. You can’t
see any anatomy in these areas due to complete
blockage of the x-ray beam by the apron.
R L

21. Lead Apron
The film below shows an extensive white area
caused by the lead apron. Note the black dots
(arrows) that represent the stitching on the
apron. The thyroid collar should never be used
for panoramic radiography since it would
routinely cause this same problem.
R L

22. Cervical Vertebrae (Spine)
If the patient is not standing straight, the cervical
vertebrae may block the x-ray beam as the tubehead
travels behind the patient at an upward angle. This
results in a radiopaque area that extends up through
the middle of the film (arrows below). The teeth/bone
are faintly visible in the radiopaque area (not
completely blocked out as with the lead apron).

23. Cervical Vertebrae (Spine)
This film shows the radiopaque “shadow” caused by
the cervical vertebrae in a patient that is not standing
straight. Note that the edges of this radiopaque area
are not as sharp as those produced by the lead apron;
here the radiopacity blends in with the surrounding
bone.

24. Palatoglossal Air Space
The Palatoglossal Air Space (black area below) is
caused by failure to keep the tongue against the palate
during exposure. This makes it difficult to diagnose
periapical pathology, which also is dark, in the maxillary
area. Many patients have difficulty complying with the
instructions to keep the tongue against the palate
during exposure and this space is often seen. As long
as you instruct the patient, this would not be considered
an error.

25. Palatoglossal Air Space
The arrows in the film below identify the
palatoglossal air space.
R

26. Static Electricity
Static electricity appears as black lines or dots on
the film, often having a tree-branch appearance. It is
caused by removing the film from the box or
cassette too quickly, creating static discharge.

27. Static Electricity
This film shows two major errors, one of which is the
interesting aliigator-like static electricity at the top of
the film. The small black circles at the bottom of the
film are also caused by static. What is the other error
seen on this film?
The film is extremely underexposed. This was
probably caused by placing the film outside the
intensifying screens (not between them) in a flexible
cassette.
R L

28. Failure to Remove Appliances
As part of patient preparation, appliances should be
removed from the mouth. In this patient, the complete
upper denture was left in the mouth. This would not
require a retake, since the acrylic of the denture base
allows x-rays to pass through and the bone is clearly
visible.
R L

29. Failure to Remove Appliances
In this patient, both upper and lower removable partial
dentures were left in the mouth. In this case the metal
frameworks obscure large areas of the teeth and the
film should be retaken.
R L

30. Failure to Remove Tongue Ring
Anything removable in the mouth should be taken out
before exposing a panoramic film. In this patient, a
tongue “ring” was left in place and blocks a couple of
teeth. Does the tongue ring need to be removed for
periapical films?
No. The tongue ring would be behind the film and would
not cause a problem, assuming normal film placement.
R L

31. Glasses
Glasses should routinely be removed for panoramic
exposures. The bottom part of the frame/lenses may
obscure the periapical area of the maxillary anterior
teeth. What other error is evident on this film?
The head is tipped up too much. Notice the reverse
smile and the proximity of the hard palate to the roots
of the maxillary teeth.
R L

32. Patient Movement
It is important for the patient to remain still during
a panoramic exposure. This film shows excessive
patient movement (unknown cause) and must be
retaken.
R L

33. Patient Movement
This film shows much more subtle movement
(arrow), resulting in an uneven inferior border of
the mandible. This might be misinterpreted as
being the result of a fracture.
R

34. Double Exposure
It is preferable to process films immediately after
exposure. If cassettes are laid aside for later
processing, the operator may inadvertently pick up a
cassette that has already been exposed and use it
again. This results in a double exposure as seen below.
What other error is evident on this film?
Static electricity at the bottom of the film.
R

35. Incorrect Exposure Settings
If incorrect exposure factors are selected for a
patient (kVp, mA), a film that is too light
(underexposed) or too dark (over-exposed) may
result. The film would normally be retaken.
overexposure underexposure