Latest technology digital opg (orthopantomogram) machine has been started

An Orthopantomogram (OPG), also known as an "orthopantogram" or "panorex", 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.
Dental 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. 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. Finally a compromise
is selected by each manufacturer and results in magnification factors which vary strongly along the film (15%-30%). 
The patient positioning is very critical in regard to both sharpness and distortions.
The result is an image showing sharply the section along the mandible arch and blurred the rest. For example, the more
radio-opaque anatomical region, the cervical vertebras (neck), shows as a wide and blurred vertical pillar overlapping
the front teeth. The path where the anatomical elements are recorded sharply is called "focal path".Dental 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. 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. Finally a compromise is
selected by each manufacturer and results in magnification factors which vary strongly along the film (15%-30%). The
patient positioning is very critical in regard to both sharpness and distortions.
The result is an image showing sharply the section along the mandible arch and blurred the rest. For example, the more
radio-opaque anatomical region, the cervical vertebras (neck), shows as a wide and blurred vertical pillar overlapping
the front teeth. The path where the anatomical elements are recorded sharply is called "focal path".

Latest technology digital opg(orthopantomogram)machine has been started in hospital setup itself

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