Dentinogenesis Flashcards
1
Q
describe pre-dentine
A
- first bit of dentine
- organic matrix only
- beside pulp
2
Q
what is dentine composed of?
A
- 70% mineral - hydroxyapatite
- 20% organic matrix:
- collagen (mainly type I)
- Extracellular matrix/ground substance:
- dentine phosphoproteins
- proteoglycans
- lipids
- 10% water
3
Q
describe dental papilla
A
contains blood vessels
4
Q
describe enamel organ
A
no blood vessels in it, get nutrition from connection tissue
5
Q
A
1) dental papilla cells divide
2) cells enlarge and cross acellular space
3) increased synthetic/secretory organelles
4) organic matrix secreted = predentine
5) odontoblasts retreat secreting predentine
6) predentine mineralises forming dentine
6
Q
describe initial mineralisation
A
- matrix vesicles involved
- crystals grow and aggregate obscuring collagen
- basal lamina disintegrates
signals start of enamel formation
7
Q
describe mineralisation of dentine
A
- once hydroxyapatite crystals formed
- hydroxyapatite grows in a spherical form - globular
- calcospherites - these eventually fuse (mineralizes in spheres)
8
Q
what are the different types of dentine?
A
- mantle dentine
- circumpulpal dentine
9
Q
A
10
Q
A
11
Q
A
12
Q
A
13
Q
A
14
Q
A
15
Q
A
16
Q
A
22
Q
A
