37 - Physiology of saliva + Role of GCF Flashcards
Saliva
A complex fluid that continually bathes part of the tooth exposed within oral cavity
Produced by ⇢ Parotid, Submandibular + sublingual glands ⇢ secreted into mouth
Functions:
- Moistens the mouth
- Facilitates speech
- Lubricates food
- Contains digestive enzymes
Organic components
Amylase ⇢ Starch ⇢ fructose + glucose
Lysozymes ⇢ prevent bacterial infections in the mouth
Histatins ⇢ prevents fungal infections
Secretory IgA ⇢ immunity mediator
Major enzymes
a-Amylase ⇢ secreted by acinar cells of parotid + submandibular glands
- Starts digestion before swallowing
- Optimum PH of 7.4
Lingual lipase ⇢ secreted by acinar cells of sublingual gland
- NOT active until stomach PH reaches acidic level
- Optimum PH of 4
Kallikrein
- Vasodilator secreted by acinar cell of ALL major salivary glands
Functions of saliva:
Protection
Washing action against non-adherent bacteria + debris
Clearance of sugars
Mucins provide lubrication to avoid attrition
Lubrication
Coat food
Soft + Hard tissues allow food to travel w/minimal infection
MG1 + MG2 provide fluid layers w/high film strength around surfaces + food
Tissue repair
Active constituents of saliva promotes tissue growth + differentiation
Antimicrobial activity
Active constituents of saliva acts as a physical barrier
Associated w/immune + non-immune defences
Proteins include:
Lysosome Lactoferrin Peroxidase
These have anti-microbial activity as they disrupt cellular/mitochondrial functions
Aggregation
Inhibit bacterial attachment + adherance of carcinogenic organisms
Anti-Viral activity
Secretory IgA can directly neutralise viruses
Buffering capacity
Resistance against PH changes at an arbitrary point
Phosphate Protein Carbonic acid + bicarbonate
Function is to maintain PH + acid neutralisation
Tooth integrity
Active constituents present at tooth surface:
Calcium, phosphate, fluoride:
- Post-eruptive maturation + reparation of enamel
- ⇡ hardness
- ⇡ Resistance of demineralisation
Original pellicle of enamel is replaced w/a constantly replenished salivary film
Digestion
Solubilisation of food by action of amylase + lipase ⇢ begins digestive process
Saliva allows formation + swallowing of food bolus
Taste
Saliva solubilises food substances ⇢ they can be detected by taste receptors on taste buds
Saliva produced by minor salivary glands around circumvallate papillae ⇢ binds these substances + presents them to taste receptors
Oral hygeine
Saliva washes away food debris + non-adhering MOs from mouth
