CSA chemistry of enamel caries Flashcards
(41 cards)
When do ionic materials precipitate?
if surrounding solution is above saturation
when do ionic materials dissolve?
if surround solution is below saturation
what is Solubility product for apatite Ca10(PO4)6(OH)2?
o Ksp = [Ca]10 x [PO4]6 x [OH]2
what must occur for salt to precipitate>
solubility product must be exceeded
what increases solubility of apatite>
carbonate/magneisum
What decreases solubility of apatite?
fluoride so less prone to dissolve
what if there is more fluoride in HAP?
less HAP need to be in solution before dissolution occurs
what form should phosphate in saliva be in?
soluble form to be available for HAP
WHAT Happens to Phosphate in higher pH?
less soluble
what happens when below critical ph
ENAMEL WILL DISSOLVE
What happens above pH 5 to dominant phosphate ion?
has one proton, HPO42-
What happens BELOW pH 5 to dominant phosphate ion?
phosphate= H2PO4-1
what happens when enamel dissolves?
ionicn bonding between Ca2+ ions weakened and ions move into solution
in a lesion radiograph what is the translucent zone?
leading front of lesion
in a WS lesion radiograph what is the body zone?
where bulk material has been lost from
in a WS lesion radiograph what is the surface zone?
surface of lesion
What is pore structure of a carious lesion of enamel like in translucent zone?
reasonable size
What is pore structure of a carious lesion of enamel like in dark zone?
smaller pores
What is pore structure of a carious lesion of enamel like in body of lesion?
large holes
What is 30% of material coming out of translucent zone?
Calcium
what is the amount of caarbonate and magnesium lost in translucent zone?
10 times more concentrated and being lost than there is present
What is 35% of material coming out of dark zone?
Calcium
Is more magnesium or carbonate lost in dark zone?
Magnesium
What is calcium being lost like in body of lesion?
similar to amount present but amount lost is low, same with Mg
