Source:http://linkedlifedata.com/resource/umls/id/C0180020
SPN: A dental X-ray exposure alignment device is a device intended to position X-ray film and to align the examination site with the X-ray beam.,SPN: A dental X-ray position indicating device is a device, such as a collimator, cone, or aperture, that is used in dental radiographic examination. The device is intended to align the examination site with the X-ray beam and to restrict the dimensions of the dental X-ray field by limiting the size of the primary X-ray beam.,UMD: Collimators designed to define the dimensions and direction of a beam of x-ray radiation, usually by eliminating the peripheral, more divergent part of the x-ray beam. These collimators typically consist of tubes, cones, and diaphragms or systems of diaphragms made of radiation-absorbing materials and interposed in the pass of the beam. Radiographic collimators are widely used in radiographic and fluoroscopic units and systems.