A dental panoramic radiograph, showing the maxilla and mandible, all the teeth including the “wisdom teeth,” the frontal and maxillary sinuses, the nasal cavity and the temporomandibular joint and other near by head and essentials of dental radiography and radiology pdf anatomy. A panoramic radiograph is a panoramic scanning dental X-ray of the upper and lower jaw. It shows a two-dimensional view of a half-circle from ear to ear. The patient’s skull sits between the X-ray generator and the film.
The X-ray source is collimated toward the film, to give a beam shaped as a vertical blade having a width of 4-7mm when arriving on the film, after crossing the patient’s skull. Also the height of that beam covers the mandibles and the maxilla regions. The arm moves and its movement may be described as a rotation around an instant center which shifts on a dedicated trajectory.
The manufacturers propose different solutions for moving the arm, trying to maintain constant distance between the teeth to the film and generator. Also those moving solutions try to project the teeth arch as orthogonally as possible. It is impossible to select an ideal movement as the anatomy varies very much from person to person. The patient positioning is very critical in regard to both sharpness and distortions.
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. X-ray dosage on it compared to the bigger size. X-ray technology, which is based on electronic sensors and computers. One of the principal advantages compared to film based systems is the much greater exposure latitude.
This means many fewer repeated scans, which reduces costs and also reduces patient exposure to radiation. Lost X-rays can also be reprinted if the digital file is saved. X-ray exposure, that no darkroom is required, and that no chemicals are used.