Saliva

Question 1

Facts

Answer 1

• 99% water, it moistens + lubricates all parts of mouth
• helps movement of tongue, lips + cheeks
• contains substances help neutralise acid responsible for tooth decay
• antiacid function called buffer action
• digestive action is caused by enzyme called ptyalin
• this starts digestion of carbohydrates

Question 2

Functions

Answer 2

Lubrication, cleansing, digestion, antacid, antibacterial

saliva contains many component which differ between the glands - each component having its own role or function

Question 3

Minerals - sodium, calcium, potassium, + their electrolytes - such as phosphates

Answer 3

neutralise dietary acids + buffering to maintain stable PH in oral cavity
allow mineralisation of plaque to form supra gingival calculus

Question 4

2. Salivary amylase

Answer 4

digestive enzyme that begins starch digestion, before food is swallowed, also called ptyalin

Question 5

3. Antibodies

Answer 5

immunoglobulins (especially IgA) present to fight infection such as periodontal disease + promote wound healing
IgA is the most common antibody of the immune system

Question 6

4. Leucocytes

Answer 6

white blood cells, defence mechanisms against oral infection + disease

Question 7

5. Mucus

Answer 7

from the mucous secretory cells,

aids lubrication - allows speech + swallowing to occur

Question 8

6. Other enzymes

Answer 8

aids defence of oral cavity + promotes wound healing

Question 9

7. Water

Answer 9

carrying agent for other components - aids lubrication - dissolves food particles to allow taste sensation - cleansing action by dislodging food from around teeth

Question 10

Mucous secretory cells

Answer 10

produce thick, mucus like secretion which aids lubrication in the oral cavity, + contains minerals + enzymes

Question 11

Serous secretory cells

Answer 11

produce a thin, serum like secretion containing antibodies + electrolytes

Question 12

Patients with low mineral content

Answer 12

mainly watery saliva tend to develop little calculus but have a higher caries incidence than pts with high mineral content saliva.

Question 13

Those with high mineral content

Answer 13

tend to have thick, stringy saliva + develop calculus more readily, in the absence of adequate oral hygiene. they also tend to have lower incidence of caries, often despise inadequate dietary sugar control

Question 14

The position of the salivary ducts

Answer 14

against the upper molars + lower incisors allow dental calculus to build up easily in these areas

Question 15

Saliva is slightly alkaline

Answer 15

due to its electrolyte components, but maintains the oral cavity at a neutral PH of 7 between meals. when PH falls below 7 following intake of food, the mineral content of saliva acts to neutralise the acidic environment + raise PH again
If PH level falls to critical level of 5.5, enamel demineralisation will occur