Dental Radiography

Unit 8 & 9

17 cards·by mwoehler

Resolution

Quality of recording separate images of small object

Sharpness/definition

ability of the receptor to define or reproduce the distinct outlines of an object

fog

overall gray appearance on file, light exposure or film left in room

Photoelectric effect

x-ray photon collides with an electron and gives up its energy

comptom effect

x-ray photon collides with an electron and gives off only part of its energy

dental x-rays

produce both compton and photoelectric effects

leakage radiation

misdirected electrons in the coolidge tube, contained within the tube head

secondary radiation

scattered, source is struck, not target

half value layer

thinkness of the filtering material that will decrease the x-ray beam by half

characteristic radiation

not a direct hit, orbiting electron is hit

tube housing

absorbs stray radiation, protects the coolidge tube from damage, provides grounding, prevents overheating

thermonic emission - electrons

electrons are released from the filament

electron cloud

outer electrons acquire enough energy to move away from the filament the cloud is formed

centered focal spot

best quality x-rays are produced

focusing cup

focuses electrons into a narrow beam towards the target

electrons strike the target

energy is convered to xrays

what is needed to produce xrays

electrons, high voltage, target to stop electrons