lecture 4 - radiation protection

Question 1

is x-radiation harmful

Answer 1

yes, all radiation is harmful and causes change in living cells

Question 2

who is responsible for prescribing dental images

Answer 2

the dentist

Question 3

recall adult patient with high caries risk

Answer 3

BWX every 6-18 months

Question 4

recall child patient with low caries risk

Answer 4

BWX 12-24 months

Question 5

recall adult perio patient

Answer 5

as needed

Question 6

protection equipment for tubehead

Answer 6

filters
collimators
PID

Question 7

inherent filtration

Answer 7

primary beam passes through glass window, insulating oil, and tube head seal
0.5-1.0 mm of aluminum

Question 8

added filtration

Answer 8

aluminum disks between tube head seal and collimator
0.5 mm increments

Question 9

collimation

Answer 9

restricts beam size and shape, reduce patient exposure

Question 10

how big should a beam be after exiting PID

Answer 10

no more than 2.75 inches

Question 11

position-indicating device (PID)

Answer 11

directs x-ray beam
short (8 inches) or long (16 inches)

Question 12

what size PID is perferred

Answer 12

long

Question 13

protection equipment for patient

Answer 13

lead apron
thyroid collar
digital sensor/fast film
aiming rings

Question 14

lead apron

Answer 14

protects reproductive and blood-forming tissues from scatter radiation

Question 15

thyroid collar

Answer 15

protects thyroid gland from scatter radiation
only for intra-oral exposures

Question 16

inverse square law

Answer 16

adequate distance: at least 6 feet away from tube head
perpendicular to beam (90-135 degrees)

Question 17

which unit of measurement measures the effect of absorbed radiation of tissue

Answer 17

rem or sievert

Question 18

maximum permissible dose (MPD)

Answer 18

maximum dose equivalent that a body is permitted to receive within a specific period of time with little to no injury

Question 19

occupationally exposed persons

Answer 19

50 mSv/year (0.5 Sv or 5 rem/year)

Question 20

non-occupationally exposed persons

Answer 20

1 mSv/year (0.01 Sv or 0.1 rem/year)

Question 21

pregnant persons

Answer 21

0.5 mSv/month of pregnancy

Question 22

maximum accumulated does (MAD)

Answer 22

occupationally exposed workers must not exceed an accumulated lifetime radiation dose
lifetime does shouldn’t exceed the worker’s age multiplied by 10

Question 23

how much radiation should a 45 year old no exceed?

Answer 23

450 mSv
45 x 10 mSv = 450 mSv

Question 24

ALARA

Answer 24

as low as reasonably achievable

Question 25

informed consent

Answer 25

insuring the patient has all information necessary to make an educated decision for themselves