An OPG (Orthopantomagram) is a panoramic scanning dental X-ray of the upper and lower jaw. It is also sometimes called by the proprietary name Orthopantomagraph or Panorex. It shows a flattened two-dimensional view of a half-circle from ear to ear. Panoramic x-rays allow images of multiple angles to be taken to make up the composite panoramic image, where the maxilla (upper jaw) and mandible (lower jaw) are in the viewed area. The structures that are outside the viewed area are blurred. At some stage in your dental treatment, your dentist will likely take an OPG.
The principal advantage of panoramic images/OPGs:
Broad coverage of facial bones and teeth including the TMJ (temperomandibular joint)
Low patient radiation dose
Convenience of examination for the patient
Ability to be used in patients who are restricted in opening their mouth
Short time required for producing the image
Useful visual aid in patient education and case presentation
Your dentist will ask you to remove any jewellery or metallic items from around the head and neck area as it can interfere with the image, blocking the x-ray. The OPG usually takes about 3 mins to complete, only 20 seconds of this are the image being taken.