Production of X-rays Flashcards
What is the random change in direction after hitting something?
Scattering
What is the deposition of energy in tissues?
Absorption
What is the number of X-rays photons in a defined area of beam?
Intensity
What is the reduction in intensity of beam due to scattering and absorption?
Attenuation
What is the removal of electron from neutral atom to give negative electrons and positive ions?
Ionisation
What is the ability of photons to pass through or into tissues/ materials?
Penetration
What are the 4 X-ray interactions?
Completely scattered with no loss of energy
Absorbed with total loss of energy
Scattered with some absorption and loss of energy
Transmitted unchanged
What is the amount of radiation absorbed by the patient?
Radiation dose
Order the electromagnetic spectrum
Gamma ray
X-ray
Ultraviolet
Visible
Infrared
Microwave
Radio
What are the 2 types of image receptors?
Film
Digital
What are the 2 types of film receptors?
Direct action film
Indirect action film
What are the 2 types of digital films?
Solid state sensor
Photo-stimulable phosphor
What type of image receptors are intra oral X-rays?
Direct film
How do direct film receptors work?
X-rays act directly on silver halide crystals in film emulsion
What type of image receptors are extra oral radiographs?
Indirect film
How do indirect film receptors work?
Light from intensifying screens act on silver halide crystals in film emulsion
How do digital PSP receptors work?
Latent image produced by interaction of X-rays with phosphor layer on plate
What type of digital receptor is better tolerated?
PSP
In PSP, what is produced when x-ray energy is stored in the electrons of the phosphor crystals?
latent image
In PSP, what is stored energy released as?
blue light
How is the image on the plate erased after scanning?
exposing phosphor to bright light
what are 2 types of solid state?
CCD and CMOS
What do x-rays hit within the sensor of CCD?
scintillator
what differs CCD to CMOS?
CCD - each pixel is connected
CMOS - each photocell is electrically isolated
what type of solid state uses less power?
CMOS
What is exposure?
the amount of x-rays to produce an image
What is PACS?
Picture archiving and communicating system - image storing
What are the sizes of digital receptors -PSP?
0, 1, 2, 4
What are PSP sizes 0, 1, 2 used for?
periapical and bitewings
what are PSP sizes 0, 1 used for?
periapical anterior mouth of adult and all regions for children
what are PSP size 2 used for?
posterior mouth of adults
what is PSP size 4 used for?
occlusal
what are the sizes of solid state receptors?
size 2
