10/7: Radiation Risks/Benefits

Question 1

Deterministic effects of radiation have a

Answer 1

Threshold and severity is proportional to dose

Question 2

This is a side-effect of head and neck cancer treatment

Answer 2

Radiation erythema

Question 3

Stochastic effects of radiation have

Answer 3

No dose threshold
probability of occurrence is proportional to dose
severity of effects does not depend on dose

Question 4

1 day of background radiation is how much exposure?

Answer 4

8.5 microSv

Question 5

Stochastic effects to somatic cells cause what?

Answer 5

malignancies

Question 6

Stochastic effects to germ cells cause what?

Answer 6

Genetic mutations that are inheritable

Question 7

This effect is only seen in the person affected, NOT future generations

Answer 7

Somatic mutations/effects

Question 8

This effect is not seen in the person affected, ONLY in future generations

Answer 8

Genetic effects/mutations

Question 9

What is the sequence of radiation injury?

Answer 9

Latent period
Period of injury
Period of recovery

Question 10

How can you have a shorter latent period?

Answer 10

Larger dose

Question 11

What factors modify effects on radiation?

Answer 11

Total dose
Dose rate
Oxygen
Area exposed
Cell type and function
Age

Question 12

Who is at risk for radiation in terms of age?

Answer 12

Pediatric patients

Question 13

This is the amount of radiation which in light of present knowledge will not produce any harmful effects

Answer 13

Maximum permissible dose

Question 14

What are the occupational limits? (dental people)

Answer 14

5 rem or 50 mSv

Question 15

What are the non-occupational limits?

Answer 15

.5 rem or 5 mSv

Question 16

What are the pregnant occupational limits?

Answer 16

0.5 rem or 500 eRem

Question 17

What is an example of external background radiation?

Answer 17

Cosmic

Question 18

What is an example of natural internal background radiation?

Answer 18

Radon

Question 19

The least radiosensitive organ is the

Answer 19

Muscle

Question 20

Medicine radiation exposure is how much?

Answer 20

⅙ total exposure

Question 21

What cancer has the highest risk for dental radiographic exposure?

Answer 21

Leukemia
Thyroid

Question 22

Patients who are fearful of the risks of radiographs should be made aware of what 3 things?

Answer 22

Magnitude of risk (small)
What we can do to minimize risk
Benefits of radiographs

Question 23

What are the benefits of radiographs?

Answer 23

Interproximal caries diagnosis
Severity and depth of caries
Periodontal bone loss
Root configuration
Periradicular pathology
Basal bone pathology in jaws
Location of 3rd molars
Anatomy assessment for implants

Question 24

Compared to visual assessment, how many times more likely are you to identify caries?

Answer 24

3x

Question 25

What kinds of bone loss can you have?

Answer 25

Generalized
Localized
Horizontal
Vertical

Question 26

Lingual (Li) root canal on the mandibular 1st molars are common in which populations?

Answer 26

Asian
Native americans