Orthopantomograhm OPG

OPG The orthopantomogram (also known as an orthopantomograph, panotomogram or an OPG) is a panoramic single image radiograph of the mandible, maxilla and teeth. It is often


OPG

encountered in dental practice and occasionally in the emergency department; providing a convenient, inexpensive and rapid way to evaluate the gross anatomy of the jaws and related pathology.

Patient position

During an OPG the patient remains in a stationary position (seated or standing) while both the x-ray source and film rotate in combination around the patient. The x-ray source rotates from one side of the jaw, around the front of the patient, and then to the other side of the jaw. The film rotates opposite to the x-ray source behind the patient. It takes a few seconds during which the patient must remain completely still.

Technical factors

panoramic projection
paused respiration (departmentally dependent)
centering point
- Frankfort's horizontal line is perpendicular to the floor
- laser lights will be vendor specific however
  - central laser light in the midsaggital plane
  - axial laser light at the IOML
  - lateral laser light at the lateral incisor
orientation
- lanscape
detector size
- OPG specific detector
exposure
- 70-80 kVp
- 8-15 mA over a number of seconds
grid
- yes

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