Ex 1- Amelogenesis

Question 1

Enamel is a composite _______ mineral with apatite crystals oriented in a complex 3D pattern

Answer 1

biological

Question 2

Amelogenesis occurs _______ dentinogenesis during the crown stage of odontogenesis

Answer 2

after

Question 3

Although dentin must be present for enamel to form, it is also true that _________ must be present in order for dentinogenesis to occur

Answer 3

ameloblasts

Question 4

_______ _____ occurs between epithelial cells of the enamel organ and mesenchymal cells of the dental papilla ie ameloblasts must be present for dentinogensis to occur

Answer 4

reciprocal induction

Question 5

Unlike the other 3 mineralized tissues, enamel does not have an __________ preenamel phase

Answer 5

unmineralized

Question 6

The structurally indentifying majority part of enamel (rod, rod sheath, and interrod substance) is formed as a _____ step process

Answer 6

two

Question 7

The _____ step of amelogensis is secretion of an immature or partially mineralized (___ % inorganic, ____% organic and H2O) enamel

Answer 7

first
30
70

Question 8

Once the width of this type of enamel has been deposited in an area, the ____ step of amelogensis occurs. It involves significant influx of additional mineral coincident with the removal of _____ material and _____. This area of enamel is described as having _______ and ______ phases

Answer 8

second
organic
H2O
secretory
maturative

Question 9

What are the 3 things that are required for enamel (all 3 mineralized tissues) to be formed?

Answer 9

1. specialized cell
2. alkaline phosphatase
3. rich blood supply

Question 10

The specialized cell of enamel is the ______ a differentiated _____ cell of the enamel organ

Answer 10

ameloblast

inner

Question 11

Alkaline phosphatase is located in the _______ _______ layer of the enamel organ

Answer 11

stratum intermedium

Question 12

Rich blood supply is located in the ______ ______ part of the tooth germ

Answer 12

dental follicle

Question 13

Cells at the _____ most area of the inner layer of the enamel organ are the first to differentiate into ________. The process continues apical toward the ______ _____ of the enamel organ

Answer 13

coronal
ameloblasts
coronal loops

Question 14

The acellular or clear layer of dental papilla is the future site of the ______

Answer 14

DEJ

Question 15

What are the 3 main stages of amelogenesis?

Answer 15

1. Presecretory
2. Secretory
3. Postsecretory

Question 16

What are the 2 phases of the presecretory stage?

Answer 16

1. Morphogenetic

2. Histodifferentiation of ameloblasts

Question 17

Ameloblasts differentiate _____ odontoblasts but dentin is mineralized _______ enamel

Answer 17

before

before

Question 18

What are the 6 phases of the secretory stage?

Answer 18

1. Inner immediately mineralized secretrion
2. Interrod substance secretion
3. Rod secretion
4. Maturation phase
5. Outer immediately mineralized secretion
6. Final ameloblast secretion phase

Question 19

What is the phase of the postsecretory stage?

Answer 19

Protective phase; reduced

Question 20

During the presecretory stage _______ phase a clear or _______ layer is seen between the inner cells of the enamel organ and peripheral cells of the dental papilla

Answer 20

morphogenetic

acelllular

Question 21

During the presecretory stage _________ phase an area of inner cells where differentiation begins from here it proceeds _______

Answer 21

histodifferentiation

cervically

Question 22

During the presecretory stage histodifferentation phase seen along the acellular layer of the tooth germ are forming _______,_______ (columnar epithelial cells)

Answer 22

odontoblasts

ameloblasts

Question 23

During the secretory stage _______ _________ phase an ultra-thin layer of inner ______ or structureless enamels that is ________ mineralized upon secretion is formed. The distal ends of ameloblasts are _______ or even here

Answer 23

inner mineralized
rodless
immediately
smooth

Question 24

During the secretory stage Phase 2 _____ ______ ______ the distal end of the ameloblast changes from a smooth to a _______ process

Answer 24

Interrod substance secretion

Tomes’

Question 25

Tomes' processes of adjacent ameloblasts secrete the _____ substance that encircles _____ processes

Answer 25

Interrod | Tomes'

Question 26

______ _____ is the space initially occupied by Tomes' process

Answer 26

Tomes' pit

Question 27

Interrod substance is _____ mineralized (immature enamel) ____% organic and water and ____% inorganic. Walls of the pits are surrounded by the ______ substance of enamel

Answer 27

partially 70 30 interrod

Question 28

The structural unit of enamel is _____

Answer 28

rod

Question 29

1 ameloblast forms __ rod

Answer 29

1

Question 30

2 or more ameloblasts from ________ substance

Answer 30

interrod

Question 31

During the secretory stage rod secretion phase, Tome's processes move out of the pit as the ________ move toward the future enamel surface.

Answer 31

ameloblasts

Question 32

As the Tomes' process withdraws it secretes a _____ ____ ____ into the pit. This continues until the length of the immature interrod substance and rod is reached

Answer 32

partially mineralized rod

Question 33

Tome's processes are at the______ end of the ameloblats next to partially mineralized (immature) enamel which indicate we are in the _____ _____ phase

Answer 33

distal | rod secretory

Question 34

Before maturation phase beings, the rod and interrod enamel is ______ ______ having a _____ percentage of organic substance and H2O ___% and inorganic ____% and Tomes' process is the _____ end of the ameloblast

Answer 34

``` partially mineralized (immature) higher 70 30 distal ```

Question 35

During the secretory stage maturation phase the distal end of the ameloblast alternates between an even or _____ edge and ______ or ruffled edge

Answer 35

smooth | uneven

Question 36

When the edge is _____ or ____ the ameloblast is resorbing or removing organic material and water

Answer 36

even | smooth

Question 37

When the edge is _____ or _____ the ameloblast is secreting; mineral salts (inorganic) into the partially mineralized enamel

Answer 37

uneven | ruffled

Question 38

Maturation is complete when the percentages are ___% inorganic, ___% organic, ___% H2O

Answer 38

96 1 3

Question 39

______, the early stages and phases are occurring

Answer 39

Apically

Question 40

During the secretory stage maturation phase the distal end of the ameloblast alternates btw an even configuration to an uneven or ruffled border. This means that the Tomes' process is ____ ______ present

Answer 40

no longer

Question 41

During the secretory stage _____ mineralized phase the outer rodless enamel is formed. This enamel is mineralized ______

Answer 41

outer | immediately

Question 42

Rodless enamel is NOT secreted by tomes' processes bc they do NOT contain ______ ____

Answer 42

enamel rods

Question 43

The _____ _____enamel is the last mineralized secretion of ameloblasts but NOT its _____ secretion

Answer 43

outer rodless | final

Question 44

During the secretory stage final ameloblast secretion phase the ____ _____ is formed

Answer 44

basal lamina

Question 45

The basal lamina is the final secretion of ______ and is a non-mineralized strcuture

Answer 45

ameloblasts

Question 46

Outer rodless enamel is the final _______ secretion of the ______

Answer 46

mineralized | ameloblasts

Question 47

During the postsecretory stage _____ phase _____ ______ epithelium is formed as a remnant of enamel organ and is the protector of enamel until the tooth enters the _____ _____

Answer 47

protective reduced enamel oral cavity

Question 48

The ___ cell layers of enamel organ come together to form the ____ _____ _____ cavity

Answer 48

4 | reduced enamel epithelium

Question 49

The reduced enamel epithelium is the protective layer of the enamel that becomes the _______ ______ during emergence of tooth into oral

Answer 49

junctional epithelium

Question 50

The reduced enamel epithelium is attached to the enamel surface by the _____ ______ the final secretion of the ameloblast

Answer 50

basal lamina

Question 51

The maturation phase, for each permanent tooth, from initiation to completion takes approximately ___ years

Answer 51

5

Question 52

Mature enamel: __% inorganic __% organic ___% H2O

Answer 52

96 1 3

Question 53

Immature or partially mineralized enamel: __% inorganic __% organic + H2O

Answer 53

30 | 70

Question 54

The initial mineralizaton of primary teeth is ___ - ____ wks IU

Answer 54

15-19 wks IU

Question 55

The completed mineralization of primary teeth is __-__ months PN

Answer 55

2-11 months

Question 56

The initial mineralization of permanent teeth is from ____ - _____ years

Answer 56

Birth-9 years

Question 57

The completed mineralization of permanent teeth is from ___ - ____ years

Answer 57

5-14 years

Question 58

_____ ______ _____ is a remnant of the enamel organ in the crown area and protector of enamel

Answer 58

reduced enamel epithelium

Question 59

______ ______ is the final secretion from ameloblasts

Answer 59

basal lamina

Question 60

_____ ______ enamel is the last mineralized secretion of ameloblasts

Answer 60

outer rodless

Question 61

_____ ______ enamel is the initial mineralized secretion of ameloblasts

Answer 61

inner rodless