Oucod Oral Histology Lecture 1 Development

Front 1

______________ cells induce epithelial cells to migrate downwards.

Back 1

neural crest

Front 2

At what week in development does downward growth of the epithelium begin?

Back 2

Week 5 or 6

Front 3

Dental and vestibular lamina form during what stage of growth?

Back 3

bud stage

Front 4

what are the three morphological stages of tooth growth?

Back 4

bud, cap and bell stage

Front 5

basal cells of the tooth bud, continuous with basal cells of the oral epithelium, will become what layers later on?

Back 5

inner and outer enamel epithelial layers

Front 6

Name the four layers of the enamel organ from outside to inside.

Back 6

Outer enamel epithelium, stellate reticulum, stratum intermedium, inner enamel epithelium

Front 7

the dental papilla is located adjacent to the (inner/outer) enamel epithelium?

Back 7

inner

Front 8

the dental sac is located adjacent to the (inner/outer) enamel epithelium?

Back 8

outer

Front 9

the inner enamel epithelium will become what cells?

Back 9

ameloblasts

Front 10

the dental sac will become _____________?

Back 10

peridontium

Front 11

the dental papilla will become ____________?

Back 11

dentin and pulp

Front 12

cells at the top of the dental papilla will differentiate into _____________?

Back 12

odontoblasts

Front 13

at the end of the cap stage, the dental lamina becomes ____________?

Back 13

perforated

Front 14

What is the function of the stratum intermedium?

Back 14

to nourish ameloblasts

Front 15

at what stage does the dental lamina begin to disintegrate?

Back 15

bell stage

Front 16

the cervical loop is the junction of what two layers?

Back 16

inner and outer enamel epithelia

Front 17

the cervical loop is present until the completion of the _________?

Back 17

crown

Front 18

What begins deposition in the appositional stage?

Back 18

dentin and enamel

Front 19

T or F: capillaries surround the enamel organ during the appositional stage?

Back 19

True

Front 20

the successional lamina will help to form what structure?

Back 20

permanent or secondary tooth

Front 21

to what side of the primary tooth bud does the successional lamina form?

Back 21

lingual

Front 22

Name the four causes of congenitally missing teeth.

Back 22

1. physical disruption of obstruction of the dental lamina
2. space limitation
3. functional abnormalities of the dental epithelium
4. failure of initiation of the underlying mesenchyme

Front 23

____________ is the absence of 6 or fewer teeth.

Back 23

hypodontia

Front 24

_____________ is the absence of more than 6 teeth.

Back 24

oligodontia

Front 25

gene mutations can be responsible for (oligodontia/hypodontia)

Back 25

oligodontia

Front 26

what are the 5 functional stages in cytodifferentiation?

Back 26

formative, maturative, protective, organizing, morphogenic

Front 27

during what functional stage does the tome's process form?

Back 27

formative stage

Front 28

the ruffled border of the ameloblast forms during which funtional stage?

Back 28

maturative

Front 29

List the functional stages of ameloblast cytodifferentiation in order.

Back 29

Morphogenic, organizing, formative, maturative, protective

Front 30

Both ameloblasts and odontoblasts are (polarized/non-polarized).

Back 30

polarized

Front 31

What does it mean that a cell is polarized?

Back 31

The nucleus is at one end of the cell

Front 32

The secretory ends of odontoblasts and ameloblasts are both located at the ______________?

Back 32

basal lamina

Front 33

Odontoblasts and ameloblasts both communicate via _____________?

Back 33

gap junctions

Front 34

Ameloblasts communicate with each in order to produce a ________________? (odontoblasts do this also)

Back 34

5um of product per day

Front 35

Product formation from ameloblasts and odontoblasts starts in (fissures/cusps)?

Back 35

cusps

Front 36

Predentin is made from (epithelial/connective tissue) cells?

Back 36

connective tissue

Front 37

Dentin resembles bone because it is _____________ in a proteoglycan/glycoprotein rich ___________________.

Back 37

collagen fibers, ground substance

Front 38

Ameloblasts produce two glycoproteins. What are they?

Back 38

amelogenin, enamelin

Front 39

Dentin mineralizes (before/after) deposition?

Back 39

after

Front 40

T or F: enamel contains hydroxyapatite at deposition?

Back 40

True

Front 41

Maturation of enamel involves the (enlargement/addition of) hydroxyapatite crystals at the expense of the matrix?

Back 41

enlargement

Front 42

Odontoblastic processes became encased by _______________?

Back 42

the dentinal tubule

Front 43

_____________ cells stay vital after eruption while ____________ cells are lost.

Back 43

odontoblast, ameloblast

Front 44

Which is capable of repair when damaged, enamel or dentin?

Back 44

dentin

Front 45

When does root formation begin?

Back 45

1. When the crown is completed
2. the tooth begins erupting
3. when the cervical loops grows down to become the epithelial root sheath and epithelial diaphragm
4. ERS induces odontoblast formation

Front 46

What encloses the pulp cavity at the apical end?

Back 46

epithelial diaphragm

Front 47

The opening in the epithelial diaphragm is called ____________?

Back 47

the apical foramen

Front 48

the epithelial root sheath grows (apically/coronally)?

Back 48

apically

Front 49

name two functions of the epithelial root sheath.

Back 49

1. shapes root and induces odontoblasts
2. shapes DCJ (dentino-cemental)

Front 50

the epithelial root sheath grows at the (same/slower/faster) rate as eruption of the crown?

Back 50

same

Front 51

Cytodifferentiation in the root begins where?

Back 51

at the cervix of the tooth

Front 52

Does the inner enamel epithelium differentiate in the root?

Back 52

No (no enamel)

Front 53

Basement membrane on (inside/outside/both sides) of epithelial root sheath breaks down?

Back 53

both sides

Front 54

The parts of the epithelial root sheath that are left behind when it disintegrates are called _________________?

Back 54

epithelial rests

Front 55

epithelial rests are also known as ______________?

Back 55

Islands of Malassez

Front 56

What must disintegrate before cementoblast cytodifferentiation can occur?

Back 56

epithelial root sheath

Front 57

What cells are the precursors of cemtoblasts?

Back 57

fibroblasts

Front 58

What must be calcified before cementum can form?

Back 58

predentin

Front 59

Cementum is laid down as _________________?

Back 59

cementoid

Front 60

Which type of cementum is layed down first, acellular or cellular?

Back 60

acellular

Front 61

secretion of cementum traps fibers of the ______?

Back 61

PDL

Front 62

Most cementum is deposited (before/after) eruption and occlusion?

Back 62

after

Front 63

What is the difference between a cementoblast and a cemetocyte?

Back 63

A cementocyte is a cementoblast which has been trapped in cementum

Front 64

What structure is embedded in the PDL?

Back 64

epithelial rests

Front 65

(Cementum/enamel/dentin) most resembles bone?

Back 65

cementum

Front 66

T or F: deposition of cementum stops shortly after occlusion?

Back 66

False, deposition continues throughout life

Front 67

What enters through the apical foramen?

Back 67

nerves, aterioles and venules

Front 68

What determines the diameter of the apical foramen?

Back 68

the epithelial diaphragm

Front 69

Multiple roots are formed by fusion of the (epithelial root sheath/epithelial diaphragm)?

Back 69

epithelial diaphragm

Front 70

Growth of multirooted teeth is the (same/different) than single rooted teeth?

Back 70

same

Front 71

Primary teeth are anchored in a __________ while permanent teeth are anchored in a _____________?

Back 71

bony trough, bony socket

Front 72

T or F: permanent teeth have interdental bone while primary teeth do not.

Back 72

True