dentin-pulp complex

Question 1

pulp in the crown

Answer 1

pulp chamber

Question 2

pulp in the roots

Answer 2

root canal

Question 3

pulp at the cusps

Answer 3

pulp horns

Question 4

pulp and PDL meet

Answer 4

apex

Question 5

first PDL fibers begin at

Answer 5

the dentino-cemental junction (DCJ)

Question 6

the apical foramen may not be at the

Answer 6

anatomical apex

Question 7

composition of dentin

Answer 7

• inorganic (70%)
• organic (20%)
• water (10%)

Question 8

main inorganic component

Answer 8

hydroxyapetite

Question 9

main organic component

Answer 9

collagen (type I and 5)

Question 10

predentin

Answer 10

• unmineralized matrix (collagen)

- mineralized into dentine

Question 11

primary dentin

Answer 11

• forms majority of tooth

- surrounds pulp

Question 12

dentin in contact with enamel or cementum

Answer 12

mantle dentin

Question 13

secondary dentin

Answer 13

• develops after root formation has been completed

- near roof and floor of chamber

Question 14

tertiary dentin

Answer 14

-produced in reaction to stimuli (caries, attrition, resto)

Question 15

dentin formation begins during which stage

Answer 15

bell stage

Question 16

onset of root formation

Answer 16

tooth eruption

Question 17

how much dentin if formed when tooth reaches functional position

Answer 17

2/3

Question 18

final completion of root is __ after eruption

Answer 18

18 months

Question 19

root dentin requires which cells

Answer 19

hertwig’s epithelial root sheath

Question 20

pulp size ___ over lifetime

Answer 20

decreases

Question 21

which cells form dentin

Answer 21

odontoblasts

Question 22

odontoblasts differentiate from

Answer 22

ectomesenchymal cells of dental papilla

Question 23

dentinal tubules are lined by ___ dentin and connected through a mesh of ___ dentin

Answer 23

lined by peritubular dentin, connected by a mesh of intertubular dentin

Question 24

hypomineralized dentin where zones of mineralization (calcospherites) have failed to fuse

Answer 24

interglobular dentin

Question 25

odontoblast processes follow __ shape path

Answer 25

S

Question 26

what happens to dentin near the surface of the pulp chamber

Answer 26

converges due to smaller area => increase permeability

Question 27

bacteria filling dentin tubules

Answer 27

dead track

Question 28

dentinal tubules that become occlude with calcified material

Answer 28

sclerotic dentin (translucent dentin)

Question 29

4 zones of pulp

Answer 29

1) odontoblastic zone (pulp perifery) 2) cell-free zone of weil 3) cell rich zone 4) pulp core

Question 30

differentiation of odontoblasts occur during __ stage

Answer 30

bell stage

Question 31

stages of life cycle of odontoblasts

Answer 31

differentiating stage, formation stage, quiescent stage

Question 32

when odontoblasts differentiate, they (preodontoblasts) align along

Answer 32

basement membrane (separating dental papill ana IEE)

Question 33

assume a columnar shape (basal nuclei and apical projections) and align along BM

Answer 33

formation stage

Question 34

odontoblasts produce collagen fibers, which accumulate and cause

Answer 34

the basal lamina to disappear

Question 35

dentin tubules are formed around

Answer 35

odontoblast processes