EX2; Eruption and Shedding Flashcards Preview

May14 Oral Histology > EX2; Eruption and Shedding > Flashcards

Flashcards in EX2; Eruption and Shedding Deck (35):
1

What are the three stages of eruptions

preemergence
prefunctional
functional

2

What is the main direction of movement in the preemergence stage

facially

3

What is the main direction of movement in the prefunctional stage

occlusially

4

What is the main direction of movement in the functional stage

mesially

5

This stage starts with the appearance of dental lamina and continues to the appearance of reduced enamel epithelium and Hertwig's root sheath, just prior to the start of root dentin formation

preemergence stage

6

This is the movements a tooth makes to attain and maintain its position in the jaw

eruption

7

Which is the only direction in which the tooth will not move

apically

8

The movements of eruption are a cellular activity involving different cell types of the periodontal ligament; which are

cementoblasts
osteoblast
osteoclast
fibroblast

9

This is the most numerous cell type of the PDL, involved in the secretion(blast) and lysis(coast) of the extracellular substance, and may become a contracting cell

fibroblast/clast/myocyte (myofibroblast)

10

What is the main direction of movement of the primary and secondary tooth germ

facially

11

What is the reduced enamel epithelium attached to the enamel surface by

basal lamina

12

What are the two main functions of Hertwig's root sheath

determines the number of root canals and the root dentin outline

13

What is the bone crypt

become the alveolar process

14

This stage starts with root dentin formation and ends when tooth reached the occlusal plane

prefunctional stage of eruption

15

What is the main direction of movement of the pre functional stage

occlusially

16

What does the apical end of Hertwigs epithelial sheath continue as

the diaphragm; determining the number of root canals

17

Where is the reduced enamel epithelium in relation to Hertwig's root sheath

it is over/above it

18

During the root sheath diagram stage, what happens

the number of root canals is determined
tooth erupts occlusially from this level

19

During the root sheath elongating, what happens

determines root dentin outline
diaphragm remains at the relatively same level

20

What happens upon the root dentin forming

the sheath breaks up; cementum forms on exposed dentin

21

These are remnants of epithelial cells from Hertwig's root sheath in the periodontal ligament, appearing during the pre functional stage of eruption

Epithelial rest of Malassez

22

During the pre functional stage, what happens to the merged oral epithelium and the reduced enamel epithelium

they undergo cell death

23

What does the reduced enamel epithelium become

junctional epithelium

24

The basal lamina is considered this type of basement membrane

"double" basement membrane
it extended around the entire junctional epithelium

25

True or False
the basal lamina can attach to dentin

False; this also affects implants

26

What is the arrangement of collagen fiber bundles of the PDL

onliquely

27

This stage starts at the occlusal plane and physiologically continues throughout life

functional stage

28

What is the main movement in the functional stage

mesially

29

What are the changes to the junctional epithelium during functional eruption

attached to enamel
attached to enamel and cementum
attached to cementum

30

Functional arrangement of the principal fiber bundles of PDL occurs during which stage

functional stage

31

During the functional stage, what changes occur to dentin

attrition
dead tracts
reparative (tertiary) dentin

32

What are the changes during the functional stage of eruption

continued dentin formation
reduced pulp tissue volume
ectopic mineralization

33

This is the physiologic elimination of primary teeth caused by the resportive action of osteoclasts

shedding

34

Where does the odontoclast originate

in the bone marrow

35

If the reduced enamel epithelium comes in close contact to the osteoclast cells, what could occur

it could break down and cause the enamel to damage