3. Fluoride And Dental Caries Flashcards
Aims of lecture
What is hydroxyapatite? Formula?
When does fluoride get incorporated into teeth?
Pre-eruptive enamel structure
Oral retention of fluoride
1.
Fluoride may be firmly bound and incorporated into the crystals directly into the structure within the tooth
↳ form fluorohydroxyapatite
- fluorohydroxyapatite = lower solubility than hydroxyapatite so a lower ph is needed to cause demineralisation
↳ incorporated into crystals directly into structure
2.
- it may be loosely bound as calcium fluoride
OR
-some loosely bound as fluoride absorbed onto apatite surface as opposed to being intrinsic within its structure
3.
- Might be held in calcium fluoride compounds within the plaque biofilm on the tooth surface
- within plaque it is found at concentrations Of 5-10 ppm
- it is reversibly bound to free calcium & dispersed as CaF2
- it is 95% bound
Enamel demineralisation
- Critical pH
- What is critical pH mean
- What reaction occurs at critical pH
Demineralisation Vs remineralisation
Demineralisation, remineralisation cycle
(what happens?)
Hydroxyapatite → fluoride incorporation equation
Is fluoroapatite or hydroxyapatite more soluble?
fluorohydroxyapatite has a lower solubility than hydroxyapatite
Effect of fluoride on apatite solubility?
Calcium fluoride
Mechanism of loosely bound fluoride in remineralisation
Mechanism of remineralisation
Antibacterial effects of fluoride
How does fluoride get into bacteria?
Effect of fluoride on bacteria
Effect of fluoride on plaque?
Fluorosis?
