Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

saliva > inorganic components of saliva > Flashcards

inorganic components of saliva Flashcards

1
Q

typical salivary pH

A

6-7.4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

why is pH important in mouth?

A

-mantaining ionic product for hydroxyapatite
-isoelectric point for salivary protein precipitation on tooth surfaces
-optimal pH for salivary enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Explain Stephan’s curve

A

-pH decreases to 4.5 due to fermentation of carbohydrates by plaque microorgs generating acids
-hydroxyapatite dissolves below 5.5, some demineralisation occurs
-pH restored to neutrality due to salivary buffering, new mineral precipitated
-for remineralisation, pH must be above critical pH (5.5), takes 20-40mins to happen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what does data on wax chewing graph show

A

-if pH below 5.5, hydroxyapatite dissolves, the longer it stays below this value the more tooth mineral will be lost
-greater amount of sucrose given, the lower the plaque pH
-stimulating saliva increases buffering capacity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

rate of ph with flow rate

A

higher flow rates increases salivary buffering (increases pH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

effect of flow rate on pH of saliva

A

Higher the flow rate higher the pH
-more buffering/alkaline species
-this is due to bicarbonate ions competent (most important buffer)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are bicarbonate ions

A

important buffer at high flow rates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how are bicarbonate ions produced?

A

-by striated epithelium of secretory ducts and parotid glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does conc of bicarbonate vary?

A

-bicarbonate content of saliva increases with metabolic activity of salivary glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

range of bicarb

A

1mM-60mM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

how much bicarb in mechanically stimulated saliva

A

15mM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Effect of flow rate on bicarbonate conc in saliva

A

Increased salivary flow results in increased bicarb concs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is pka of bicarbonate

A

At pH 6.1 equal conc of carbonic acids and bicarbonate ions
-as pH falls, forward reaction will be favoured

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

bicarbonate formula

A

HCO3-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

where is bicarbonate produced

A

Bicarbonate derived partly from plasma and partly from metabolic activity of salivary glands
-Carbonic acid conc in plasma is stable at 1.3milimolar and is equiliburm with alveolar carbon dioxide conc in lungs
-conc in gland increases with increased salivary flow due to increased metabolic activity
H2O + CO2–H2CO3–HCO3- + H+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are sodium and potassium ions used for

A

-counter ions to preserve electrical neutrality
-sodium counter ion for bicarbonate
-potassium counter ion for phosphate

17
Q

conc range of sodium

A

6-26mM

18
Q

conc range of potassium

A

14-32mM

19
Q

effect of increase in flow rate on Na and K ions

A

increases Na+, K+ stays same

20
Q

what is role of Mg ions in saliva?

A

role unclear
possible: cellular degradation, early carious attack

21
Q

conc range of Mg

A

0.2-0.5mM

22
Q

effect of increase in flow rate on Mg ion

A

decreases

23
Q

what is Ca++ secreted by

A

major salivary glands

24
Q

what does Ca bind with

A

complexes with calcium-binding salivary proteins

25
Q

role of Ca ions

A

-mantainance of ionic product for hydroxyapatite

26
Q

conc range for Ca

A

1-2 mM

27
Q

effect of flow rate increase on Ca +

A

stays same

28
Q

effect of flow rate on protein in saliva

A

-some proteins bind to calcium
-increases protein

29
Q

What are phosphate ions role

A

-acts as buffer esp in unstimulated saliva
-important in mantanaince of ionic product for hydroxyapatite

30
Q

conc range of phosphate ions

A

2-13mM

31
Q

effect of increase flow rate on phosphate ions

A

decrease, increased flow rate produces more alkaline pH due to increased bicarbonate

32
Q

Diff phosphate species

A

-changes the proportions of diff ionic phosphate species. H2PO4- decreases and HPO42- and PO43- increase–these less protonated phosphate ions important to solubility of tooth mineral

33
Q

What can increasing Ca and phosphate ions do

A

-increasing ca and phosphate ions in saliva will encourage reprecipitation of mineral BUT too much ca and po4 will lead precipitation of minerals at other sites leading to tartar

34
Q

What is saturated/supersaturated

A

-when sufficient ions of salt, solution is saturated
-above threshold is supersaturated
-saliva is supersaturated with hydroxyapatites at neutral pH

35
Q

Conc of fluoride ion in saliva

A

0.001-0.005mM

36
Q

where is fluoride ions found

A

porous enamel, including caries (higher conc in plaque)

37
Q

what is role of fluoride

A

replaces OH in HAP lattice structure, increasing its stability
-facilitates HAP precipitation and promotes remineralisation

38
Q

read 3 slides on HAP

A

one note

saliva (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions