Oral Environment 3

Question 1

Is the film of saliva in the mouth in motion or static?

Answer 1

in motion

Question 2

What is the average volume of saliva in the mouth?

Answer 2

1.1ml

Question 3

Where is salivary flow highest in the mouth?

Answer 3

in lingual, lower regions

Question 4

Where is salivary flow lowest in the mouth?

Answer 4

labial, buccal regions

Question 5

Where are cariogenic substances retained longest?

Answer 5

where flow is lowest (labial, buccal regions)

Question 6

What does cariogenic mean?

Answer 6

causing tooth decay

Question 7

What is meant by clearance?

Answer 7

Refers to the rate at which substances are removed from the mouth

Question 8

What are the important oral health aspects of clearance?

Answer 8

• Removal of ‘harmful’ materials
• Retention of ‘beneficial’ materials

Question 9

What is rapid clearance?

Answer 9

high salivary flow rates

Question 10

How do plaque micro-organisms generate acid?

Answer 10

by metabolising sugars such as sucrose

Question 11

What is a graph of the plaque pH change over time called?

Answer 11

a stephan curve

Question 12

What does below 5.5 on the Stephan curve indicate?

Answer 12

demineralisation

Question 13

What does chewing gum increase in saliva?

Answer 13

clearance
buffering

Question 14

What is the biggest advantage in chewing gum?

Answer 14

increased buffering capacity decreasing caries

Question 15

Is increased flow rate effective with chewing gum?

Answer 15

yes but not after a while as it subsides to just above normal unstimulated rate

Question 16

What are examples of bulk caloric (cariogenic) sweeteners?

Answer 16

sucrose, fructose, glucose, lactose

Question 17

What are non-caloric/high intensity sweeteners (non-cariogenic)?

Answer 17

• Aspartame
• Cyclamates
• Saccharin
• Sucralose

Question 18

What are low caloric sweeteners?

Answer 18

• Mannitol
• Sorbitol
• Xylitol

Question 19

At what value is xerostomia classified?

Answer 19

50% of normal flow rate

Question 20

What is the condition in which calculous stones block salivary ducts?

Answer 20

sialolithiasis

Question 21

What are the causes of decreased salivary flow?

Answer 21

side effect of drugs
radiotherapy
diseases

Question 22

What is the most common cause of xerostomia?

Answer 22

drugs

Question 23

What does radiotherapy damage?

Answer 23

glands, epithelia

Question 24

What can be done to avoid radiotherapy damage?

Answer 24

stimuli salivary glands through drug before e.g. propranolol

Question 25

What is a autoimmune condition that can affect salivary glands?

Answer 25

sjogens syndrome - autoimmune disease which attacks tear and salivary glands

Question 26

What position of caries is associated with reduced salivary flow?

Answer 26

cervical

Question 27

What are the consequences of reduced salivary flow?

Answer 27

increased caries
increased oral disease e.g. stomatitis
reduced taste and sensation
dysaesthesia (burning mouth)
loss of protective proteins and enzymes

Question 28

How can you treat Xerostomia?

Answer 28

drugs
saliva substitutes (mucin based, cellulose based)

Question 29

What is the critical pH at below which demineralisation occurs?

Answer 29

5.5

Question 30

What increases in saliva after prolonged period of chewing gum (apart from buffering capacity)?

Answer 30

salivary pH as bicarbonate concentrations are high and bicarbonate is alkaline

Question 31

Why does flow rate of saliva decrease after a prolonged period of chewing gum?

Answer 31

gum loses taste (gustation)
gum becomes soft (mechanical