Define dental caries

Question 1

Define dental caries
What is it instigated by?
Leads to?

Answer 1

reversible (early stages) but progressive disease of dental hard tissues
instigated by bacteria from fermentable carbohydrates in the plaque biofilm
leading to demineralisation

Question 2

Define caries process
Where does it originate?
How is it formed…
What does it create?

Answer 2

originates as metabolic activity in the plaque biofilm
biofilm begins to form few mins after brushing teeth
is then absorbed as the acquired pellicle - containing salivary proteins + glycoproteins
In a short time - bacteria colonise the pellicle - extracellular polysaccharides and salivary proteins
increase density of developing biofilm, changing bacterial population, pH and oxygen tension all combine to create a cariogenic environment

Question 3

Define carious lesion
Result of….
Requires certain factors….

Answer 3

Result of metabolic activity in the plaque biofilm
If factors such as plaque, diet, saliva, mineral ions, time tip balance towards demineralisation
histological stages of progressive lesion formation lead to cavitation

Question 4

4 factors of caries process

Answer 4

bacteria
tooth surface
fermentable carbohydrates
time

Question 5

Bacterias role in caries process
What is the primary causative bacteria
two other types of bacteria known to interact and allow lesion to progress

Answer 5

colonisation within the plaque biofilm
several hundreds of diff types
primary - streptococcus mutans
lactobacillus and bifidobacterium

Question 6

Fermentable carbohydrates role in carious lesion
What metabolises and produces?
Which causes?

Answer 6

plaque bacteria metabolises certain dietary carbohydrates (sucrose + glucose)
producing organic acids (lactic, acetic, propionic) on tooth surface
causes the pH to fall in 1-3 mins and initiate demineralisation

Question 7

What occurs @ demineralisation and remineralisation of the tooth surface
What protects the teeth

Answer 7

plaque pH can fall in 1-3 mins
pH can take up to 60 mins to get back to norm levels - by protective buffering capacity of saliva
demineralisation/remineralization cycle occurs continuously on the tooth surface

Question 8

critical pH of enamel and dentine

Answer 8

5. 5

6. 2

Question 9

How does the present of saliva help to remineralise

Answer 9

With its capacity to buffer plaque acids, provide a source of remineralising calcium and phosphate ions to the tooth surface
remove food debris
lubricate/protect tooth surfaces

Question 10

What occurs to lesion whilst still in enamel

Answer 10

can be arrested and possible reversed in early stages

Question 11

What occurs to lesion once into dentine

Answer 11

Can become inactive, but if destruction of organic collagen matrix has occurred extensively this cannot be reversed