study this second questions Flashcards
source of electrons
negative cathode
low voltage energy source goes to
filament
phosphor plates size
0, 1, 2, 4
what is correct for film
larger focal length (want small focus length for digital)
constant potential CD
acute radiation syndrome is
ionization
why is tungsten good
it has low cost, thermionic radiation, heat conductivity
laser beam and light scintillation
PSPP
what does film badge do
xray exposure of the operator
dental staff max dose
50mSv 5 rem
2012 recall patient with no disease but high caries risk
bitewing radiograph and selective PA
most susceptible
nerve
muscle
bone
hematopoetic
hematopoetic
aluminum filter for 70KeV
1.5mm
filtration removes
low keV
when do we treat pregnant patient
emergency pain
what leads to image distortion the most
horizontal angulation
skin from therapeutic radiation
direct (think erythema)
caries
indirect radiation
relative biological harm
equivalent dose
compare biological effects of different types of radiation
energy absorbed by tissue
absorpted
Calculate risks of radiation to human tissues on common scale
Used to assess risk of non-uniform radiation to localized part of body and degree to which this would increase a person’s “whole body” risk
effective dose
measurement of energy for threshold ion pairs
exposure
cotton roll placement
between biteblock and opposing teeth
(NOT between bitebock and imaging teeth)
what acute is most lethal
CNS/CVS
factors enhancing effects of xradiation
a. increased oxygen tension
b. decrease dose
c. older patient
d. decreased mitotic rate
e. specialized cells/mature cells
a
effect of radiation in the oral cavity
a. loss of taste
b. excess saliva
c. excess fluid
a and xerostomia
osteoradionecrosis question about damage
disruption in the vasculature of osseous structures
coronal damage is due to
indirect effects
largest source of man made
xrays
