This document discusses panoramic x-rays and their use in dental practice. It describes how panoramic x-rays provide a wider view than traditional dental x-rays and allow visualization of gross anatomy and pathology. The document outlines advantages like field size and lower radiation dose compared to full mouth x-rays. Disadvantages discussed include potential image quality issues from distortion and superimposition. Proper patient positioning within the focal trough is emphasized as important for diagnostic image quality.

1. Panoramic x-ray
Islam Kassem
Level 6
ikassem@dr.com

2. ikassem@dr.com
2D panoramic imaging

3. High Quality Images, Effortlessly
•
ikassem@dr.com

4. Concepts of Panoramic Radiography
Introduction
Dr.walaa
ikassem@dr.com

5. Introduction to Panoramic
Radiography
• Commonplace in dental practice
• Considered essential in radiographic
diagnosis
• 30% of dental units sold are
panoramic
ikassem@dr.com

6. Introduction to Panoramic
Radiography
• “Panorama” means unobstructed
view of a region in any direction
• Panoramic radiograph show greater
coverage than periapical and
bitewing radiographs
ikassem@dr.com

7. Introduction to Panoramic
Radiography
• New technique
• Introduced in 1959
• Employs scanography (slit beam) &
curved surface rotational
tomography
ikassem@dr.com

8. Client Dose from Panoramic
Radiography
• 10 times less radiation than a
complete intraoral survey using long,
round PID & E+ film
• 4 time less radiation than a bitewing
survey using long, round PID and E+
film
ikassem@dr.com

9. Indications for Panoramic
• Pathology-cysts, tumors
• Trauma-fractures
• Growth & development
• Client management
• Edentulous
• Localization: anatomy, objects,
implant placement
• Carotid artery condition
ikassem@dr.com

10. Advantages of Panoramic
Radiography
• Field size
• Quality control
• Simplicity
• Time & rapidity of the procedure
• Client cooperation
• Dose
• Minimal infection control
• Gross anatomy & pathology visible
ikassem@dr.com

11. Disadvantages of Panoramic
Radiography
• Image quality
• Focal trough limitations
• Equipment costs
• Overuse
ikassem@dr.com

12. Disadvantages of Panoramic
Radiography
• Image quality
– Magnification
– Distortion
– Poor definition compared to intraoral
– Overlap
– Superimposition & ghost images
ikassem@dr.com

13. Disadvantages of Panoramic
Radiography
• Poor image quality due to
– Tomographic process
– Increased object-film distance
– Use of intensifying screens
– Faster film with larger crystals
ikassem@dr.com

14. Disadvantages of Panoramic
Radiography
• Focal Trough (Image Layer)
– Areas outside are not visible
– Size & shape limits imagery to those
structures which “fit” into the image
layer
– Size & shape not adjustable so not all
client’s arches image equally well
ikassem@dr.com

15. Disadvantages of Panoramic
Radiography
• Distortion
– Vertical & horizontal distortion with
variations causes uneven magnification
ikassem@dr.com

16. Disadvantages of Panoramic
Radiography
• Superimposition & Ghost Images
– All objects in the field of the beam, even
those outside of the image layer are
projected onto the film but most are not
seen.
– Objects with the greatest density are
projected in two places on the film
• Intended (useable image)
• Ghost image (reversed, higher, blurred)
ikassem@dr.com

17. Disadvantages of Panoramic
Radiography
• Superimposition & Other Imaging
Quirks
– Ghost images may hide pathosis
– Soft tissue shadows may mimic
pathosis
ikassem@dr.com

18. ikassem@dr.com

19. Focal Trough
• An imaginary, three-dimensional curved area
that is horseshoe shaped.
• This is a very important concept because
many technique errors are caused by
improper positioning of the patient’s jaws
within the focal trough.
• When the jaws are positioned within this area,
the radiograph will be clear.
• When the jaws are positioned outside of this
area, the images on the radiograph will
appear blurred or indistinct.
ikassem@dr.com

20. ikassem@dr.com

21. Components of the Panoramic Unit
• Panoramic x-ray tubehead
• Head positioner
• Exposure controls
ikassem@dr.com

22. ikassem@dr.com

23. The Head Positioner
• Each panoramic unit has a head positioner used
to align the patient’s teeth as accurately as
possible.
• Each head positioner consists of a chin rest,
notched bite-block, forehead rest, and lateral
head supports or guides.
• Each panoramic unit is different, and the operator
must follow the manufacturer’s instructions on
how to position the patient in the focal trough.
ikassem@dr.com

24. .
ikassem@dr.com

25. ikassem@dr.com

26. ikassem@dr.com

27. Positioning of the Teeth
• Posterior to focal trough
• If the patient’s anterior teeth are not positioned in
the groove on the bite-block and are either too far
back on the bite-block or posterior to the focal
trough, the anterior teeth appear “fat” and out of
focus on the radiograph.
• Anterior to focal trough
• If the patient’s anterior teeth are not positioned in
the groove on the bite-block and are either too far
forward or anterior to the focal trough, the teeth
will appear “skinny” and out of focus.
ikassem@dr.com

28. ikassem@dr.com

29. .
ikassem@dr.com

30. .
ikassem@dr.com

31. ikassem@dr.com

32. Positioning of the Spine
 If the patient’s spine is not straight, the cervical
spine will appear as a radiopaque artifact in the
center of the film and obscure diagnostic
information.
ikassem@dr.com

33. ikassem@dr.com

34. ikassem@dr.com

35. ikassem@dr.com

36. ikassem@dr.com

37. ikassem@dr.com

38. ikassem@dr.com

39. ikassem@dr.com

40. ikassem@dr.com

41. ikassem@dr.com

42. ikassem@dr.com

43. Common Errors
• Patient preparation errors
• Ghost images: A ghost image looks like the real object
except that it appears on the opposite side of the film.
• Lead apron artifact: If the lead apron is placed too
high, or if a lead apron with a thyroid collar is used, a
cone-shaped radiopaque artifact results.
• Patient seating errors
• Chin too high
• Chin too low
ikassem@dr.com

44. .
ikassem@dr.com

45. ikassem@dr.com

46. Thank you
ikassem@dr.com