Title: Concepts of Panoramic Radiography Introduction
1Concepts of Panoramic RadiographyIntroduction
- DHY 202 Clinical Radiology I
- Dental Hygiene Department
- William Rainey Harper College
2Introduction to Panoramic Radiography
- Commonplace in dental practice
- Considered essential in radiographic diagnosis
- 30 of dental units sold are panoramic
3Introduction to Panoramic Radiography
- Panorama means unobstructed view of a region in
any direction - Panoramic radiograph show greater coverage than
periapical and bitewing radiographs
4Introduction to Panoramic Radiography
- New technique
- Introduced in 1959
- Employs scanography (slit beam) curved surface
rotational tomography
5Client 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
6Indications for Panoramic
- Pathology-cysts, tumors
- Trauma-fractures
- Growth development
- Client management
- Edentulous
- Localization anatomy, objects, implant placement
- Carotid artery condition
7Advantages of Panoramic Radiography
- Field size
- Quality control
- Simplicity
- Time rapidity of the procedure
- Client cooperation
- Dose
- Minimal infection control
- Gross anatomy pathology visible
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8Disadvantages of Panoramic Radiography
- Image quality
- Focal trough limitations
- Equipment costs
- Overuse
9Disadvantages of Panoramic Radiography
- Image quality
- Magnification
- Distortion
- Poor definition compared to intraoral
- Overlap
- Superimposition ghost images
10Disadvantages of Panoramic Radiography
- Poor image quality due to
- Tomographic process
- Increased object-film distance
- Use of intensifying screens
- Faster film with larger crystals
11Disadvantages 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 clients
arches image equally well
12Disadvantages of Panoramic Radiography
- Distortion
- Vertical horizontal distortion with variations
causes uneven magnification
13Disadvantages 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)
- Frommer 2001
14Disadvantages of Panoramic Radiography
- Superimposition Other Imaging Quirks
- Ghost images may hide pathosis
- Soft tissue shadows may mimic pathosis