Most people have had a an intraoral dental x-ray at one time or another. Intraoral x-rays are the ones in which the x-ray film is placed inside the mouth – the ones you bite down on , they are sometimes not the most comfortable dental x-rays. Advances in dental imaging technology have brought Orthopantomogram (OPG) dental x-ray machines into many dental offices.
Unlike intraoral x-rays the OPG x-ray machine takes a scan of the entire upper and lower jaw at the same time scanning the teeth and jaw bone from ear to ear. It takes about a minute and there is no x-ray film holders to bite down on. An OPG x-ray can show facial bones, teeth and sinuses all in one image 2D image.
For evaluating All-on-Four and other dental implant treatments, implant dentists rely on either OPG x-rays or 3D CT Scans to get a good look at the underlying bone where the implants will be placed. Implant dentists use OPG or 3D CT Scan to see if a patient is a candidate for dental implants, create treatment plans, cost estimates and quotes. From the images, the implant dentist can also see if bone or sinus grafting is needed as part of the dental implant treatment.
There are Film OPGs and Digital OPGs. Film OPGs provide one original. Digital OPGs can be copied and emailed, digital OPGs are simply uploaded to computer or emailed like a regular picture.
While scanning Film OPG x-rays onto a computer does work, the scanned Film OPG often turns out too dark to be evaluated. Special x-ray scanning machines are needed to properly digitize Film OPGs – home of office scanners will not work. For this reason, film OPG x-rays will probably be phased out over the next decade as more dentists increasingly use the more convenient, digital OPG format.
For more on OPGs, please see the OPG X-ray Reference Page on Wikipedia