Dentinogenesis - hard tissue development

Question 1

Dentine is formed by ? derived from ?? of the ??

Answer 1

odontoblasts
ectomesenchymal cells
dental papilla

Question 2

remember

Question 3

Dentinogenesis begins at the end of the ? stage and starts at the ?

Answer 3

bell
cusps

Question 4

what are the 3 stages of dentinogenesis?

Answer 4

Cytodifferentiation
- Epithelial cells tell the ectomesenchymal cells to become odontoblasts

Matrix formation - predentine

Mineralisation - to form dentine

Question 5

Dentinogenesis -> dentine formation steps

1. ??send signals for ?? to divide, grow and migrate lining up on the ??
2. Cells ? and cross ?? forming two layers
   - Layer closest to basal lamina become ?
   - Layer further from dental lamina are for ???? (on the bench)
3. Increase in secretory and synthetic ? so they can make things
   
   • The number of organelles reflects the ? of the cells
     
     • RER
     • Golgi
     • Etc.
4. ?? secreted -> ?
5. Retreat ? as they lay predentine
   
   • Gives rise to the ??
   • ?? act as epitactic heterogeneous nucleators
   • ?? burst and release factors for crystal growth
6. Predentine ? forming dentine and the basal lamina ? (signalling ??)

Answer 5

epithelial cells
dental papilla
basal lamina

enlarge
acellular space
odontoblasts
reparitive tertiary dentine formation

organelles
activity

organic matrix
predentine

inwards
odontoblast process
collagen fibres
matrix vesicles

mineralises
disintegrates
enamel formation

Question 6

overview of dentinogenesis

Question 7

Mineralisation of dentine

hydroxyapatite crystals grow in spheres, called ?, which eventually fuse

Failure of ? to fuse results in ?? -> less mineralised sections

Answer 7

calcospherites

calcospherites
interglobular dentine

Question 8

mineralisation of dentine

Question 9

name the two types of dentine

Answer 9

mantle dentine
circumpulpal dentine

Question 10

what is mantle dentine?

Answer 10

The first formed dentine

Adjacent to enamel

Collagen fibrils at 90* to ADJ

Matrix vesicles involved in formation

Question 11

what is circumpulpal dentine?

Answer 11

Rest of the dentine not adjacent to the ADJ

Collagen fibrils parallel to ADJ

No matrix vesicles in formation as crystals are already established

Question 12

Odontoblast migration

Migrate in ? shape leaving an ?? in a tubule

Answer 12

S
odontoblast process