Role of Saliva in Caries Process (Amaechi 3) Flashcards
Salivary glands
- Submandibular
- Parotid
- Sublingual
- Minor mucous
Types of saliva
- Ductal saliva
- Whole (mixed) saliva
Salivary composition
- Inorganic components
- Organic components
List the inorganic components
Na+, Cl-, HCO3, K+, Ca2+, Mg, PO4—, F-
Inorganic components are factors that affect the ________ of both the cations and anions in saliva.
Concentrations
Salivary ______ determines the concentration of ions in saliva.
Flow rate
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
- rise
- fall
- independent
_____ is the most potent stimulus for salivary secretion.
Acid
Other factors that affect salivary secretion
- Chewing gum
- Duration of stimulus
- Circadian rhythms
- Medications
___% of prescribed drugs cause xerostomia
80%
What affect does the buffering action of bicarbonate have?
Raises pH of saliva and plaque
______ 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.
Phosphate
At high salivary flow rate with its associated increase in salivary pH:
- The ______ conc. increases
- The fraction of total phosphate present as _____ increases markedly
- The ______ conc. in saliva also incresases
- Calcium ion
- PO4—
- Hydroxyl ion
Saliva promotes remineralization by overall _____ in Ip of saliva. When Ip > Ksp, the saliva is supersaturated with respect to HA.
Increase
Proteins in saliva function to maintain tooth integrity (protect against _____) and control cariogenic microflora (______ function).
- Demineralization
- Antimicrobial
Saliva maintains tooth integrity by binding _____ and releasing it as necessary.
Calcium
Saliva maintains tooth integrity by maintaining high concentrations of ____ at or near the tooth surface, thereby preventing loss of mineral from the tooth tissue.
Calcium
Saliva maintains tooth integrity by preventing the precipitation of ______ from saliva.
Hydroxyapatite
Saliva maintains tooth integrity by forming a semi-permeable membrane called a ______ which covers the tooth.
Pellicle