Enamel Caries

Question 1

what is dental caries

Answer 1

progressive destruction of tooth structure

Question 2

how is dental caries initiated

Answer 2

by microbial activity at tooth surface

crown or exp root

Question 3

what does the enviro do dental caries

Answer 3

dept on enviro
can progress unhindered to pulp
can remineralise

Question 4

what does dental plaque dept on

Answer 4

plaque bac
time
substrate
susceptible tooth

Question 5

what is erosion

Answer 5

acid demin/dissolving teeth away not same as caries as source acid of this erosion is dietary acid, saliva buffers this

Question 6

what is abrasion

Answer 6

mechanical wear with other materials

cervical notches worn away due to tooth brush abrasion something else from enviro wearing tooth

Question 7

what is attrition

Answer 7

mechanical tooth on tooth wear
occlusally and ncisally
grinding teeth wear
happen naturally also have approximal attrition shorten arch

Question 8

what is abfraction

Answer 8

bite tooth slightly flexes, not flexible cause micro cracks which wear and weaken

Question 9

what is the acidogenic theory

Answer 9

many organisms can produce acid from fermentation of sugar

many oral bac prod lactic acid

Question 10

what is the prism unit

Answer 10

prism core - centre

prism sheath - periphery

Question 11

what is the prism core

Answer 11

centre
tightly packed hydroxyapatite
little inter crystalline spaces

Question 12

what is the prism sheath

Answer 12

less well packed crystals

space contains water and inorganic mat - enamelling

Question 13

where does demineralisation start

Answer 13

prism sheath periphery

Question 14

what is the clinical appearance of enamel caries

Answer 14

white spot lesion
clean teeth and dry teeth
matt appearance

Question 15

what does the histology depend on appearance

Answer 15

refractive index of mounting medium

penetration of medium

Question 16

what is the RI air

Answer 16

1

Question 17

what is the RI enamel

Answer 17

1.62

Question 18

what is the RI water

Answer 18

1.33

Question 19

what is the RI of Quinoline

Answer 19

1.62 lare molecule

Question 20

what are the lesion zones from the advancing front

Answer 20

translucent
dark
body lesion
surface zone

Question 21

what is the translucent zone

Answer 21

1st carious change 
loss 1-2% mineral 
50% cases 
few large pores due to loss of prism periphery 
penetrated byquinolone 
- appears structure less/translucent
- quinolone fills prism periphery

Question 22

what is the dark zone

Answer 22

dark brown with quinolone 
90-95% lesions
porosity 5-10%
consists of large or small pores 
demineralisation and remineralisation occurring

Question 23

what is the body of lesion

Answer 23

largest part and centre of lesion
25-50% porosity
enamel relatively translucent
strait retzius obis

Question 24

what is the surface zone

Answer 24

relatively intact 
thick
highly mineralised high F 
porous
protected
redeposit of mineral dissolved from deeper layers

Question 25

should u probe a carious lesion

Answer 25

no

Question 26

what is arrested caries

Answer 26

remineralised changes in enviro - plaque control F, altered diet can be brown - stain

Question 27

hat are some of dentine defence mechanisms ag caries

Answer 27

reactionary tertiary dentine | sclerotic blocking tubules

Question 28

if there is rapid progression of dentine caries what is seen

Answer 28

no sclerosis odontoblasts die possibly reparative tertiary dentin

Question 29

wat is the advancing front of dentine caries

Answer 29

some of demineralised dentine acid demineralisation no bacteria

Question 30

what si the zone of bacterial penetration

Answer 30

bac in tubules lateral spread via branched tubules lactobacilli

Question 31

what is the zone of destruction

Answer 31

mixed bac pop proteolytic enzymes destroys organic matrix

Question 32

dentine can also be describe in a simpler 2 zones method

Answer 32

outer superficial zone inner deeper zone

Question 33

what is the outer superficial zone

Answer 33

highly infected irreversible demin dentine proteolytic degradation of collagen matrix

Question 34

what si the inner deeper zone

Answer 34

dentine reversibly attacked collagen matrix not severely damaged minimally infected potential to repair

Question 35

what are some points on occlusal caries

Answer 35

fissures 2 lesions hard to detect widening lesion