Introduction to Local Anesthesia/Neurophysiology

Question 1

Words associated with dentistry:

Answer 1

1. pain
2. fear
3. anxiety

Question 2

Going to the dentist is the most common fear of _____% of adults

Answer 2

21%

Question 3

In the U.S. approximately ____ of the population avoids dental care due to fear

Answer 3

10%

Question 4

The 10% of individuals in the U.S. that avoid the dentist due to fear comprise about _____ potential patietns

Answer 4

30 million

Question 5

The top 10 fear-evoking dental situations includes:

Answer 5

1. Dentist is pulling your tooth
2. Dentist is drilling your tooth
3. Dentist tells you your teeth are bad
4. Dentist holds the needle in front of you
5. Dentist is giving you a shot
6. Dentist places probe in a cavity
7. Dentist laughs as he looks in your mouth
8. Dentist squirts air into a cavity
9. Sitting in the waiting room
10. Dentist laying out instruments

Question 6

What are the ten desirable properties of local anesthesia?

Answer 6

1. no irritation to tissue
2. no permanent alteration
3. low systemic toxicity
4. effective if injected into tissue or mucous membranes
5. short onset
6. long enough duration of action for the procedure
7. potent yet not harmfully concentrated
8. no elicit allergic reaction
9. readily undergo biotransformation
10. sterile or capable of being sterilized by heat without deterioration

Question 7

List the spectrums of pain and anxiety control in dentistry:

Answer 7

1. local anesthesia
2. oral sedation
3. I.M. sedation
4. Nitrous oxide sedation
5. I.V. sedation
6. General anesthesia

Question 8

What is the function/purpose of local anesthesia?

Answer 8

Prevent generation and/or conduction of a nerve impulse

Question 9

Describe the pain pathway (1-4):

Answer 9

1. pain receptors
2. sensory nerve fiber
3. nerve pathways
4. response modulators

Question 10

What are the response modulators in the pain pathway?

Answer 10

-cortex
-thalmus
-limbic system

Question 11

The least experience of pain which a subject can recognize:

Answer 11

Pain threshold

Question 12

The greatest level of pain which a subject is prepared to tolerate:

Answer 12

Pain tolerance

Question 13

Pain tolerance is lowest at around what times?

Answer 13

4pm & midnight

Question 14

Pain tolerance is highest around what times?

Answer 14

In the morning

Question 15

When does the pain threshold change throughout the day?

Answer 15

It remains constant

Question 16

Label the following image:

Answer 16

a) CNS
b) Trigeminal ganglion
c) Foramen
d) Nerve fiber
e) pain receptors

Question 17

Label the following image:

Answer 17

a) terminal aborization
b) schwann cell
c) nodes of ranvier
d) free nerve endings
e) dendritic zone
f) axon
g) cell body

Question 18

Label the following image:

Answer 18

a) shwann cell
b) nodes of ranvier
c) myelin
d) axon
e) axoplasm
f) axolemma

Question 19

Label the following image:

Answer 19

a) axoplasma
b) axolemma

Question 20

Label the following image:

Answer 20

a) extracellular fluid
b) axolemma
c) pore
d) axoplasm

Question 21

Label whether the following ions are higher intracellularly or extracellularly:

1. K+
2. Na+
3. Pr-
4. Cl-
5. HCO3-

Answer 21

1. intracellular
2. extracellular
3. intracellular
4. extracellular
5. extracellular

Question 22

Based on the concentration gradient, K+ flows from:

Answer 22

Intracellular —> extracellular

Question 23

Based on the electrical gradient, K+ flows from:

Answer 23

Extracellular —> intracellular

Question 24

Based on the concentration gradient, Na+ flows from:

Answer 24

Extracellular —> intracellular

Question 25

Based on the electrical gradient, Na+ flows from:

Answer 25

Extracellular —> intracellular

Question 26

During the resting phase of nerve impulse transmission, the Na+ gate is:

Answer 26

Closed

Question 27

What value represents the resting phase of nerve impulse transmission?

Answer 27

-70 mV

Question 28

What happens to the Na+ gate when the fiber is stimulated?

Answer 28

Na+ gate opens, sodium enters

Question 29

What happens to the Na+ gate when the cell is depolarized?

Answer 29

Na+ gate closes

Question 30

What value represents a depolarized cell during nerve impulse transmission?

Answer 30

+20 mV