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Flashcards in Lecture #1 Deck (32):
1

When Does Ionizing radiation occur on the radiation spectrum?

10^15 or Ultraviolet light

2

What are the Natural Sources of Radiation?

Cosmic 5%
Terrestrial 3%
Radon 37%
Internal 5%

3

What are the man made sources of radiation?

X-rays 12%
CT Scans 24%
Nuclear 12%
Consumer Products 2%
other <1%

4

Gamma rays and X rays are what type of radiation?

Electromagnectic radiation

5

What is not a form of ionizing radiation?

microwaves

6

What is Becquerel (Bq)?

Si unit to messure the radioacctivity of a material

7

1 Bq=2.7X10^-11 Ci

just a fact you might want to know

8

How is exposure measured?

Coulombs/Kg
or Roentgen (R)

9

How is Absorbed dose measured?

Gray (Gy)
Rad
1Gy=100rad

10

How is equivalent dose measured?

Sievert (Sv)
or Rem
1Sv= 100 rem

11

What has higher Linear Energy Transfer (LET) than photons?

Particulate radiation

12

What is Effective dose

measure the estimated risk to humans in different tissues

13

What is Equivalent dose

The amount of radiation needed to be harmful... measures different types of radiation

14

what is Absorbed dose

Energy deposited in a kg of a substance by the radiation

15

how is effective dose measured?

Sievert (Sv)

16

Define direct Effect

Photon or secondary e- ionizes biologic macromolecules

17

Radiolysis of Water... What is it?

Photon that ionizes water causes free radicals

18

Define Indirect effect

intermediate step to mess up macromolecules... photon hits something then that something hits the organism

19

How much does Direct and Indirct effects occur from x-rays?

1/3 and 2/3 of the damages respectfully

20

What is the primary cause of radiation induced cell death?

Damaged to the DNA

21

What is Deterministic Effect?

Greater the Dose the Greater the Damage
There is an exposure threshold meaning below this there might not be any damage

22

What cells have the Highest sensitivity to radiation?

Divide regularly
Undergo little/no differentiation

23

What are some organs that have high sensitivity to radiation?

Testies
Bone
Lymphoid organs
Breasts
GI Tract
Mucous Membranes

24

Define Stochastic Effect

There is no threshold and there will always be radiation effect... you will die

25

What are 3 guiding principles to reduce dental exposure?

Justification
ALARA
Dose Limitation

26

ALARA stands for what

as low as reasonably achievable

27

dentists need what in place? (2)

Radiation protection program
good radiation safety practices

28

When should a dentist prescribe a x-ray?

after
Health History Review
Clinical assessment
Examination
susceptibility to dental diseases

29

What films should we use?

E or F speed film

30

By how much does rectangular collimators reduce exposure?

60%

31

What are the 2 types of Ionizing Radiation?

1.) Particulate Radiation
2.) Electromagnetic Radiation

32

Which radiation have a higher LET... Particulate Radiation or photons?

Particulate Radiation