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Flashcards in eruption and shedding Deck (22):
1

define eruption

movements a tooth takes to attain and maintain its postion in the jaw

2

tooth will move in all directions except

apically

3

cell types of the PDL involved in eruption

fibroblasts, cementoblasts, osteoblasts, and osteoclasts

4

fibroblast

most numerous cell in the PDL. many fns:
1. secretes ec substance
2. lysis of ec substance
3. contracting cell=fibromyocyte (connected to collagen fibers and when contracts, pulls on the collagen fibers to move the tooth)

5

stages of eruption

1. preemergence
2. prefunctional
3. functional

6

preemergence stage main direction of movement

facially

7

preemergence stage starts with

appearance of dental lamina-->bud-->cap-->tooth germ-->REE and HERS. prior to root dentin formation

8

function of HERS

1. determines root dentin outline
2. determine number of root canals

9

number of root canals is determined..

in preemergence stage via the diaphragm of HERS. 1,2,or3 openings

10

the bone crypt undergoes remodeling into the alveolar process in what stage

preemergence

11

prefunctional stage of eruption main direction of movement

occlusally

12

prefunctional stage of eruption

starts with root dentin formation and ends when tooth reaches the occlusal plane. merger (of oral epithelium and REE?)-->emergence (merged tissues undergo cell death). HERS elongates (to determine root outline), root dentin forms, HERS starts to break up at the CEJ, cementoblasts move in to form cementum on exposed dentin...this continues apically.

13

what are epithelial rests of malassez

remanents of epi cells from HERS in the PDL. appear during the pre-fn stage of eruption

14

during the pre-fn stage of eruption, REE becomes the

junctional epithelium (attached to the enamel and the cementum). has 2 basal lamina (1 connects to enamel and cementum, 2 connects to the c.t)

15

formation of the PDL and alveolar process occurs in which stage of eruption

preemergence

16

in the preemergence stage, how are PDL collagen fiber bundles arranged

obliquely..not functionally

17

functional stage of eruption direction of movement

mesially...physiologic mesial drift

18

functional stage of eruption

starts at the occlusal plane and physiologically continues throughout life. JE attachment position changes (e-->e&c-->c). functional arrangement of fiber bundles of PDL occurs.

19

changes during fn eruption

attrition, dead tracts, reparative dentin, continued dentin formation, reduced pulp, ectopic mineralization

20

reciprocal induction occurs b/w what two tissues in the fn stage of eruption

JE and the lamina propria/c.t

21

define shedding

physiologic elimination of primary teeth caused by the resorptive action of odontoclasts

22

odontoclasts originate in the

bone marrow