CON02-2001 Caries 1 & 2 Flashcards
What are dental caries?
A reversible disease process of dental hard tissue, that is instigated by the action of bacteria upon fermentable carbohydrates in the plaque biofilm at tooth surfaces, leading to proteolytic destruction of the organic component of dental tissue
What is a carious process?
The histopathological metabolic interactions occurring in the plaque biofilm, causing disease.
This encompasses the biofilm, the bacteria in the biofilm and what the bacteria are doing
What is a carious lesion?
The signs of disease on hard dental tissue (early lesions, discolouration)
What are the causative factors of caries?
Time
Carbohydrates
Susceptible tooth surface
Bacteria
How does pH affect formation of caries?
Low pH causes caries, whereas higher pH maintains sound enamel
What is high pH maintained by?
Saliva, oral hygiene, diet and fluoride
What causes low pH?
Plaque, carbohydrates and time
Define critical pH?
The pH at which saliva and plaque fluid do not become further saturated by calcium and phosphate, causing dissolution of hydroxyapatite in enamel
It is the highest pH at which there is a net loss of the dental tissue
What visual detection aids are needed to diagnose caries?
Good, sharp eyes with magnification
Loupes (with LED light)- good illumination
Clean, dryable tooth surface
What is enamel made up of?
95% is made up of hydroxyapatite
Less than 5% consist of organic matrix- ameolgenins, enamelins and water
How are enamel crystals arranged?
Prisms
What appearance does carious enamel have?
A frosty white appearance
The surface goes from smooth to rough and cavitated
What is the frosty white appearance of the tooth called?
Incipient white spot lesion
What is the appearance of longer present carious lesions?
Brown spot lesion, which is inactive and a scar of the white spot lesion
What is demineralisation of dentine due to?
Build up of lactate, acetate and proprionate
