It is similar to the film process because it involves the same image support handling and differs because the chemical development process is replaced by the scanning process. This method is in between old film based technology and the current direct digital imaging technology. The digitized images are stored and displayed on the computer screen. After X-ray exposure the plate (sheet) is placed in a special scanner where the latent formed image is retrieved point by point and digitized, using a laser light scanning.
#PANORAMA X PSP#
One particular type of digital system uses a photostimulable phosphor plate (aka PSP - Phosphor Plate) in place of the film. Other significant advantages include instantly viewable images, the ability to enhance images, the ability to email images to practitioners and clients (without needing to digitize them first), easy and reliable document handling, reduced X-ray exposure, that no darkroom is required, and that no chemicals are used. Lost X-rays can also be reprinted if the digital file is saved. This means many fewer repeated scans, which reduces costs and also reduces patient exposure to radiation. One of the principal advantages compared to film based systems is the much greater exposure latitude. The smaller size film receives 8% less X-ray dosage on it compared to the bigger size.ĭental X-rays' radiology is moving from film technology (involving a chemical developing process) to digital X-ray technology, which is based on electronic sensors and computers. There are two standard sizes for dental panoramic films: 30 cm × 12 cm (12″ × 5″) and 30 cm x 15 cm (12″ × 6″).
There are two kinds of film moving mechanisms, one using a sliding flat cassette which holds the film, and another using a rotating cylinder around which the film is wound. The patient positioning is very critical in regard to both sharpness and distortions. Finally a compromise is selected by each manufacturer and results in magnification factors which vary strongly along the film (15%-30%). It is impossible to select an ideal movement as the anatomy varies very much from person to person. Also those moving solutions try to project the teeth arch as orthogonally as possible. The manufacturers propose different solutions for moving the arm, trying to maintain constant distance between the teeth to the film and generator. The arm moves and its movement may be described as a rotation around an instant center which shifts on a dedicated trajectory. Also the height of that beam covers the mandibles and the maxilla regions. The X-ray source is rectangular collimated beam.
#PANORAMA X GENERATOR#
The patient's skull sits between the X-ray generator and the film. 7.2 Dental infection and atherosclerosisĭental panoramic radiography equipment consists of a horizontal rotating arm which holds an X-ray source and a moving film mechanism (carrying a film) arranged at opposed extremities.
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