Caries

Question 1

dental caries

Answer 1

• pain
• ugly
• reduce function
• can be prevented
  restorations but does not cure
  a disease including dental plaque bacteria.

Question 2

what is enamel tooth structure made up of ?

Answer 2

• inorganic - calcium hydroxyapatite - 95%
• organic - amelogenins &enamelins
• water

Question 3

what is dentine made up of?

Answer 3

• inorganic - calcium hydroxyapatite - 50%

- organic - collagen

Question 4

what is calcium hydroxyapatite?

Answer 4

inorganic compound composed of calcium, phosphate and hydroxide.
found in teeth and bones
give teeth a crystallised lattice like form that give rigidity

Question 5

the disease process of caries

Answer 5

• ongoing - dynamic - cycles of demineralisation and remineralisation.

Question 6

when does caries become a disease?

Answer 6

when the demineralisation happens more than demineralisation and the net outcome if mineral loss.

Question 7

caries needs - 4

Answer 7

• plaque
• time
• carbohydrate - fermentable sugars
• tooth surface

Question 8

initial colonisers of plaque bacteria - most are aerobic don’t like oxygen

Answer 8

streptococcus mutants

Question 9

plaque hypothesis

Miller 1890

Answer 9

caries is caused by bacteria plaque

Question 10

plaque hypothesis

Specific - 1960

Answer 10

caries is caused by a specific plaque bacteria

Question 11

plaque hypothesis
Ecological plaque hypothesis
Marsh, 1994 states:

Answer 11

caries is caused by specific pathogenic plaque bacteria who’s activity depend upon their environment.

Question 12

late/ secondary colonisers

Answer 12

• prophayromarlus gingivalis - perio

- actinomiyces

Question 13

sugar is turned into acid

Answer 13

acid is made by microorganisms that metabolise carbohydrates on the tooth

Question 14

acid affects plaque ph.

explain normal and critical Ph

Answer 14

resting ph 6.4

acid affects ph turning into 5.5 and minerals is lost from the tooth surface. demineralisation occurs

Question 15

critical ph of enamel

Answer 15

5.5

Question 16

in acidic conditions what occurs ?

Answer 16

demineralisation
how?
streptococcus mutant and lactobacillus increase hydrogen concentration causing the loss of
calcium and phosphate. leading to caries

Question 17

explain reminerlisation?

Answer 17

no carbohydrates = inactive bacteria
ph increases above 5.5.
= low hydrogen concentration leads to calcium and other minerals o remineralise into the lesion/ tooth

Question 18

heathy plaque bacteria 2

Answer 18

s. sanguinis

s. oralis

Question 19

streptococci

Answer 19

streptococci mutants 
round in shape 
early colonisers
produce energy by anaerobic glycolysis
operates at ph 5.5 
makes it good at metabolising sugars under acidic conditions. 
dominant in cariogenic plaque formation

Question 20

lactobacilli

Answer 20

lactobacillus acidophilus
rod like structures
secondary coloniser

Question 21

acinomyces

Answer 21

small long thin shape

Question 22

saliva

Answer 22

is saturated with calcium and phosphate ions

Question 23

other factors affection plaque ph

Answer 23

bicarbonate buffering
- high saliva flow = increase bicarbonate concentration. increasing ph 7.5-7.8.

Saliva neutralisation
- alkalinity of saliva functions as a base to neutralise acid.