Role of Saliva in Caries Process (Amaechi 3)

Question 1

Salivary glands

Answer 1

• Submandibular
• Parotid
• Sublingual
• Minor mucous

Question 2

Types of saliva

Answer 2

• Ductal saliva

- Whole (mixed) saliva

Question 3

Salivary composition

Answer 3

• Inorganic components

- Organic components

Question 4

List the inorganic components

Answer 4

Na+, Cl-, HCO3, K+, Ca2+, Mg, PO4—, F-

Question 5

Inorganic components are factors that affect the ________ of both the cations and anions in saliva.

Answer 5

Concentrations

Question 6

Salivary ______ determines the concentration of ions in saliva.

Answer 6

Flow rate

Question 7

As the saliva flow rate increases, the pH and concentrations of proteins, Na+, Cl- & HCO3 ____ while the concentration of Mg & phosphate ____. The F concentration in saliva (≈ 0.019 ppm) is relatively _______ of flow rate

Answer 7

• rise
• fall
• independent

Question 8

_____ is the most potent stimulus for salivary secretion.

Answer 8

Acid

Question 9

Other factors that affect salivary secretion

Answer 9

• Chewing gum
• Duration of stimulus
• Circadian rhythms
• Medications

Question 10

___% of prescribed drugs cause xerostomia

Answer 10

80%

Question 11

What affect does the buffering action of bicarbonate have?

Answer 11

Raises pH of saliva and plaque

Question 12

______ in saliva will bind and buffer hydrogen ions, neutralizing the acid produced by the bacteria in the plaque. This buffering action will reduce the dissolution rate up to the point when pH is at 5. At pH 5, all _______ has been protonated and the ______ has no further capacity to bind hydrogen ions.

Answer 12

Phosphate

Question 13

At high salivary flow rate with its associated increase in salivary pH:

1. The ______ conc. increases
2. The fraction of total phosphate present as _____ increases markedly
3. The ______ conc. in saliva also incresases

Answer 13

1. Calcium ion
2. PO4—
3. Hydroxyl ion

Question 14

Saliva promotes remineralization by overall _____ in Ip of saliva. When Ip > Ksp, the saliva is supersaturated with respect to HA.

Answer 14

Increase

Question 15

Proteins in saliva function to maintain tooth integrity (protect against _____) and control cariogenic microflora (______ function).

Answer 15

• Demineralization

- Antimicrobial

Question 16

Saliva maintains tooth integrity by binding _____ and releasing it as necessary.

Answer 16

Calcium

Question 17

Saliva maintains tooth integrity by maintaining high concentrations of ____ at or near the tooth surface, thereby preventing loss of mineral from the tooth tissue.

Answer 17

Calcium

Question 18

Saliva maintains tooth integrity by preventing the precipitation of ______ from saliva.

Answer 18

Hydroxyapatite

Question 19

Saliva maintains tooth integrity by forming a semi-permeable membrane called a ______ which covers the tooth.

Answer 19

Pellicle

Question 20

The pellicle prevents _____ of the tooth from rapidly dissipating into saliva and blocks the sits of ______ deposition at the tooth surface.

Answer 20

• Calcium

- Hydroxyapatite

Question 21

Salivary proteins and derivatives involved in the maintenance of the integrity of the tooth

Answer 21

• Statherin
• Acidic proline-rich proteins
• Acquired salivary pellicle

Question 22

Statherin allows saliva to be super-saturated with _______ by adsorbing to the crystal growth sites and thus preventing the formation of crystals.

Answer 22

calcium phosphate salts

Question 23

Statherin creates an environment, at the surface of the tooth, that is supersaturated with respect to ______ and ______, thus preventing diffusion of these ions out of tooth tissue.

Answer 23

calcium and phosphate

Question 24

Statherin adsorbs to the tooth surface and blocks the site of
mineral deposition, thereby inhibits additional deposition
of _______ at the tooth surface.

Answer 24

hydroxyapatite

Question 25

Acidic proline-rich proteins bind calcium in such a manner that: 1. at low calcium ionic strength, calcium can be ______. 2. at high calcium concentrations, calcium is ______. 3. at low pH, calcium binding is _____.

Answer 25

1. released 2. bound 3. reduced

Question 26

Acidic proline-rich proteins inhibits hydroxyapatite deposition at the tooth surface as it selectively adsorbs on tooth surface and blocks the sites of _________ growth, and thus prevents unwanted mineral accumulation on the tooth surface.

Answer 26

hydroxyapatite crystal

Question 27

Composition of acquired salivary pellicle

Answer 27

``` Acidic proline-rich proteins Statherin Immunoglobulins Amylase Lysozyme Salivary peroxidase Glycoproteins Serum proteins Mucins ```

Question 28

The acquired salivary pellicle is semipermeable to charged ions, thus it reduces the mobility of ___ and ____ to and from the tooth surface into the saliva and reduces the diffusion of ____ to the tooth surface during demineralization either by caries or erosion process.

Answer 28

- Ca and PO4 | - acid

Question 29

Proteins involved in control of cariogenic microflora

Answer 29

``` LACTOFERRIN LYSOZYME SALIVARY PEROXIDASE (lactoperoxidase) GLYCOPROTEINS SALIVARY AGGLUTININS HISTIDINE-RICH PROTEINS ACIDIC PROLINE-RICH PROTEINS ```

Question 30

Control of Oral Microflora occurs by causing direct lysis of the cell membrane of the microorganism (i.e., ______).

Answer 30

lysozyme

Question 31

Control of Oral Microflora occurs by interferring with growth (i.e., _________).

Answer 31

histidine-rich proteins

Question 32

Control of Oral Microflora occurs by removing nutrients from the environment (i.e., ______)

Answer 32

lactoferrin

Question 33

Control of Oral Microflora occurs by Causing aggregation of bacteria so they can be cleared by swallowing (i.e., ____, ______)

Answer 33

agglutinins, basic proline-rich glycoprotein

Question 34

Control of Oral Microflora occurs by Making products which interfere with bacterial systems (i.e., _______)

Answer 34

salivary peroxidase

Question 35

Control of Oral Microflora occurs by providing sites of attachment for micro-organisms which are organism/strain specific (i.e., ______)

Answer 35

acidic PRP

Question 36

Lactoferrin binds____, an essential bacterial nutrient, thereby making it unavailable for microbial survival and growth.

Answer 36

iron

Question 37

_____ causes lysis of the bacteria cells by enzymatic hydrolysis of the N-glycosidic linkages in microbial cell membrane.

Answer 37

Lysozyme

Question 38

Mechanism of salivary peroxidase

Answer 38

H2O2 + Thiocyanate ion --salivary peroxidase--> Hypothionate --> Inactivation of glycolytic and carbohydrate transport enzyme in bacteria (Efficacy against S. mutans is pH-dependent and is more efficient below pH 6)

Question 39

______ are proteins having a polypeptide core and | linked side chains of carbohydrate.

Answer 39

Glycoproteins

Question 40

Glycoproteins are classified into...

Answer 40

- Serous (immunoglobulins and proline-rich glycoproteins) | - Mucinous

Question 41

Immunoglobulins (secretory IgA) functions include: 1. block _____ determinants of bacteria 2. induce _______ of bacteria 3. interfere with _________

Answer 41

1. adherence 2. aggregation 3. colonization-associated enzymes

Question 42

Proline-rich glycoproteins, unlike acidic proline-rich proteins, are ______ and ______. They function to Bind to _____ and _____, a property that may interfere with attachment to the tooth surface, or may inhibit growth.

Answer 42

- glycosylated and basic | - S. mitis and S. sanguis

Question 43

Mucinous glycoproteins are very viscous and hydrophilic and function to: 1. Interact with specific ______. 2. cause _______, and hence enhance the clearance of micro-organisms since they can then be removed by swallowing

Answer 43

- micro-organisms | - bacterial aggregation

Question 44

Salivary agglutinins exhibit selective agglutinating characteristics. It specifically agglutinates ____, but not other species of Streps.

Answer 44

S. mutans

Question 45

Salivary agglutinins, if free in saliva, may cause ______ of the micro-organisms so that they can be cleared by swallowing.

Answer 45

aggregation

Question 46

Salivary agglutinins, if adsorbed to the tooth surface, may allow ______ of that organism by providing a site for attachment.

Answer 46

colonization

Question 47

Histidine-rich proteins are growth inhibitory and bactericidal for ______.

Answer 47

S. mutans

Question 48

Saliva increases clearing effect, such as clearance of: 1. ______ 2. _______

Answer 48

1. Acid from plaque | 2. Fermentable carbohydrate from oral cavity

Question 49

Saliva is a risk indicator for dental caries. Unstimulated flow rate ____ ml/min and Stimulated flow rate ____ ml/min places the individual at high caries risk.

Answer 49

- <0.2 ml/min | - <0.7 ml/min