Radiation is the emission and propogation of energy through space or a substance in the form of waves or particles. Radioactivity can be defined as the process by which certain unstable atoms or elements undergo spontaneous disintegration of decay in an effort to attain a more balanced neuclear state
true false
false true
true true
true and true
Which component of the tubehead aims and shapes the x-ray beam
the PID (position indicating device)
Within the x-ray tube electrons are generated by what:
your tungsten filament in the cathode
No filament in the anode just a tungsten target
The purpose of the anode is to what
our electrons start over in the cathode they shoot over to the anode and the tungsten target converts those electrons into photons
Which form of the x-ray beam is most detrimental to the patient and operator:
scatter radiation
Which of the following four possibilities that can occur when an x-ray photon interacts with matter is responsible for producing densities on film that make dental radiography possible
no interaction that x-ray photon is going straight through hitting that film and that’s what is causing the densities on the film.
When kVp is increased what happens
we get a higher energy x-ray beam and we have an increased pentrating ability
A film with low contrast is what
has lots of shades of grey we as hygiensts like this. High contrast means there’s lots of
white and lots of dark and that’s what dentists like. It detects periodontal disease and has lots of shades of grey (low contrast this is the answer)
mA regulates the what
quantity of electrons
using 12 mA with the exposure of 1 second will result in 12 mA if the mA is decrease to 8 the time must be increased by how much to maintain the same density on the radiograph
1.5 - 12mA * 1sec = 12 mA how are going to still maintain the 12 mA if 12/8 = 1.5 so 1.5 is how much increased to keep same 12mA
a dental hygienst changes the mA and maintains the kVp and impulses of the x-ray machine at the same setting which of following image characterists will be effected
density (density is the overall blackness we know if we increase our mA it will cause our film to be more dark and so it’s going to have increased density
Approximately what percentage of electron energy in the tubehead is converted to x-rays
one percent
Collimation of the x-ray beam serves to do what
reduces the diameter of the primary x-ray beam and (actually 70% reduction in radiation to our patient)
Radiographic intensifying screens are used to what
reduces exposure time on patient
Protection from excessive exposure to radiation is aided by the use of aluminum filters and lead diaphram. The filters reduce the amount of soft radiation reaching the patientsface and the diaphram controls the area exposed
B) true true
Increasing the mA while maintaining the kVp exposure time and film speed will result in what
increased quantity of generated x-rays
For x-ray timers calibrated in impulses how many of those impulses are in one second
60
If a source to film distance were increased without changing the mA exposure time what would happen to our radiograph
it would be lighter because those photons have a longer distance to travel
Secondary, or scatter radiation, originates when what happens
x-rays strike matter (that’s why we protect our patients and hide around a wall for ourselves)
Use of which of the following results in the greatest reduction of radiation to the patient