Eruption and Shedding

Question 1

what is eruption

Answer 1

The movements of a tooth from its formative stages within the jaws to its functional stage in the oral cavity

Question 2

why does a tooth move physiologically

Answer 2

moves in all directions except apically and continues to move throughout its existence in the oral cavity

Question 3

Stages of Eruption

Answer 3

Preemergences
Prefunctional
Functional

Question 4

Main direction of movement in the Preemergence phase

Answer 4

Facially

Question 5

Main direction of movement in the prefunctional stage

Answer 5

Occlusially

Question 6

Main direction of movement during the functional stage

Answer 6

Mesially

Question 7

when does the tooth move into the functional stage

Answer 7

Once it reaches the occlusal plane

Question 8

what is the early bone that surrounds the tooth

Answer 8

Boney Crypt

Question 9

what occures priot to root dentin formation

Answer 9

Appearance of dental lamina and continues to the appearances of reduced enamel epitheliuma nd Hertwig’s root sheath

Question 10

what is the main movement in the Preemergeces stages

Answer 10

Facially

Question 11

what does the 4 layesr of the enamel organ become after enamel formation is complete

Answer 11

Reduced enamel epithelium

Question 12

where is the cervical loop

Answer 12

Outer and inner layers of enamel organ come together

Question 13

where the outer and inner layers of the enamel organ come together

Answer 13

Hertwig’s epithelial root sheath

Question 14

what does the reduced enamel epithelium attach to

Answer 14

Attached to completed enamel surface via a basal lamina

Question 15

what is the last secretion of the ameloblasts

Answer 15

Basal lamina

Question 16

what is enamel made out of if it stains well

Answer 16

out of mostly organic matterial

Question 17

what are the functions of Hertwig’s epithelial root sheath

Answer 17

Determines root detnin outline

Determines number of root canals of the tooth

Question 18

does the roots form during the preemergences stages

Answer 18

Preemergences is before the start of root formation

Question 19

when does Hertwig’s root sheath determines number of root canals

Answer 19

Before the start of root dentin formation

Question 20

when does Hertwig’s root sheath determine root dentin outline

Answer 20

At the start of root dentin formation

Question 21

during what stage does Odonotogenesis begin

Answer 21

During the preemergences stage

Question 22

what cells differenciate during preemergence stage

Answer 22

Ameloblasts, odontoblasts, and fibroblasts

Question 23

what parts of the tooth form during preemergence

Answer 23

Apearance of crown dentin
Enamel formation begins
Appearances of pulp change
DEJ forms
Reduced enamel epithelium forms
Formation of HErtwigs epithelial root sheath
Root canal number forms
Bone crypt remodelled

Question 24

what parts of tooth formation occure in the preemergence stage

Answer 24

Epithelial stages and tooth germ apearances

Question 25

How does the Prefunction stages begin

Answer 25

with root dentin formation

Question 26

when does the prefunctional stage end

Answer 26

when the tooth reaches the occlusial plane

Question 27

Parts of the prefunctional stages

Answer 27

Root formation Merger Emergence

Question 28

how is Reduced enamel epithelium attached to the enamel surface

Answer 28

Via a basal lamina

Question 29

How does Cementum begin to form around the tooth

Answer 29

The Hertwig's epithelial root sheath begins to break up below the enamel to form the cementum

Question 30

what are the apical ends of HERS

Answer 30

area of diaphragm part during prefunctional stage of reuption

Question 31

what covers the Root dentin along the prefunctional stage

Answer 31

Hertwig's sheath over the root dentin surface

Question 32

what happens to the root sheath during the diafragm stage

Answer 32

number of root canal determines and the tooth erupts occlusially from this level

Question 33

what happens as the Root sheath elongates

Answer 33

Determines the root dentin outline | diaphragm remains at relatively the same level

Question 34

what happens to the root sheath as root dentin forms

Answer 34

Sheath breaks up | Cementum forms on exposed dentin

Question 35

how long does the process of Root dentin forming, sheath breaking up and cememntum forming occure for

Answer 35

Continues apically until root dentin outline is completed

Question 36

what are epthelial rest of Malassez

Answer 36

Remanents of epithelial cells from Hertwigs root sheath in the periodontal ligament

Question 37

when does Epithelial rest of Malassez

Answer 37

During prefunctional stage of eruption

Question 38

what happens to the tooth right before eruption

Answer 38

The merged oral epithelium and reduced enamel epithelium undergo cell death (then the most coronal part emerges into the oral cavity)

Question 39

why does a baby cry during teething

Answer 39

Not cut the tooth is moving through the oral epithelium, but because food can get caught and infect ( cells die on their own)

Question 40

What does the Reduced enamel epithelium become

Answer 40

The junctional epithelium

Question 41

where does the junctional epithelium exist

Answer 41

Between the enamel and the gingiva

Question 42

how does the Junctional epithelium attach to the enamel and the lamina propria of the free gingiva

Answer 42

the basal lamina

Question 43

what begins being formed in the prefunctional stage

Answer 43

Root dentin Epithelial rest of Malassex Cementoblasts and cementum Periodontal ligament site (collagen fibers bunfle) changing of reudced enamel epithelium to junction epithelium of free jingiva

Question 44

what breaks up during the prefuctional stage

Answer 44

Hertwig's epithelial root sheath

Question 45

How are collagen fiber bundles of the PDL arranged in the prefunctional stage

Answer 45

Not functionall (arranged obliquely

Question 46

How is the junctional epithelium attached to the tooth during the prefunctional stage

Answer 46

Via the basal lamina

Question 47

why does the tooth move mesially during the functional stage of eruption

Answer 47

Physiologic mesial drift

Question 48

when does the functional stage of eruption end

Answer 48

continues throughout life

Question 49

how does the junctional epithelium change during functional eruption

Answer 49

attached to enamel attached to enamel and cementum attached to cementum

Question 50

what happens to the principle fibers bundles of the PDL during the functional stage of eruptions

Answer 50

Functional arrangement of principle fibers

Question 51

what changes occur during funcation eruption

Answer 51

``` attrition Dead tracts reparative (teritary) dentin continued dentin formation reduced pulp tissue volume ectopic mineralizion ```

Question 52

what happens to the alveolar process during the functional stage

Answer 52

Maintenance (preservation) of alveolar process (remodeled bone crypt

Question 53

where does reciprocal induction occur during the functional stage

Answer 53

between the junctional epithelium and adjacent connective tissue (lamina propria

Question 54

what is shedding

Answer 54

The phsiologic elimination of primary teeth caused by the resorptive action of odontoblasts

Question 55

what causes shedding

Answer 55

physiologic odontoblastic activity

Question 56

where does the odonotoclast originate

Answer 56

in the bone marrow

Question 57

how does the odontoclast get to the site of activty

Answer 57

by blood vessels

Question 58

What do Odontoclasts do

Answer 58

Resorb the 3 mineralized tissues of the tooth

Question 59

what do odontoclasts look like

Answer 59

like osteoclasts (multinucleated giant cell made in the bone marrow)

Question 60

what side does the permanat dentition come from under the tooth

Answer 60

Via the lingual side

Question 61

what happens if the reduced enamel epithelium breaks down

Answer 61

the enamel is subject to damage

Question 62

the openings in the bone located lingual to the primary anterior teeth

Answer 62

Gubernaculum canals

Question 63

what passes through the gubernaculum canal

Answer 63

A gubernaculum ligament

Question 64

what is the roll of the gubernaculum ligmanet

Answer 64

passes through the canal to the dental follicle of a succeedaneous tooth and guide it to the oral cavity