Amelogenesis

Question 1

What is amelogenesis

Answer 1

the process of the formation of enamel

Question 2

It starts with..

followeded by….

Answer 2

ameloblst laying down enamel matrix and protein

mineralisation

Question 3

organic matrix contists of

which are mainly

called

Answer 3

organic material

2 proteins

Amelogenins and non-amelogenins

Question 4

non-amelogenins proteins consist of

Answer 4

Enamelin

Tuftelin

Ameloblastin

Question 5

what is the ratio of proteins in amelogenins and non-amelogenins

Answer 5

90% Amelogenins

10% non-amelogenins

Question 6

once enamel is fully formed enamel proteins make up …% of enamel

Answer 6

4

Question 7

inorganic portion of enamel of composed of

Answer 7

hydroxyapetite

Question 8

Amelogenesis is divided into 3 stages:

Answer 8

pre secretory

secretory

maturation

Question 9

what happens in the presecretory stage

Answer 9

inner enamel epithelium differitate into ameloblast

Question 10

what happens at the secrectory stage

Answer 10

ameloblasts secrect enamel matrix/proteins forming the enitire enamel thickness

Question 11

what happens at the maturation

Answer 11

Ameloblast carry out activities that help, degradation of enamel matrix and placement of minerals/inorganic material

Question 12

preesecretory stage is further divided into 2 stages

Answer 12

morphogenetic phase/ differentiation phase

Question 13

The morphogenetic phase occurs….. stage of tooth development, when…

IEE are…..

Organelle facts….

Answer 13

bell, shape of crown is established

low columnar/cuboidal

central nucelous/ golgi apparatus located at proximal part of cell (towards stratum intermedium)

other organelles are scattered

Question 14

What happens during differentitaion phase…

What happens to the cell

Organells of the cells

Answer 14

IEE become ameloblast

elongates and becomes tall and columnar

nucelus shifts proximal (towards stratum intermedium)

Golig complex shifts distal (towards dental papilla)

mitochrondia which was scattered clusters proximally

Question 15

What happens when IEE is going through changes??

Answer 15

While the changes is happening there are symentiously changes to the dental papilla cells, to change into odontoblasts, these send signalling molecules to the differentiated ameloblast. Odontoblast start to lay dentine at the end of the differentiation phase

Question 16

Ameloblast are attched to each other with the help of

located…

Answer 16

junctional complex

proximally and distally

Question 17

once the pre lyer of dentiin is formed..

T/F dentine is needed for enamel formation

Answer 17

it stimulates the ameloblasts to begin enmel formation

True just like the IEE helps in the diffention of dental papilla cells into odontoblasts, the inital layer of dentin is needed to stimulate ameloblast to lay down the enamel matrix

Question 18

in the secretory stage ameloblasts develop a ….. called the……..

Once fully devleoped it is a ………

consisting of a …..

Intialy ameloblasts only have

Answer 18

structure / tomes process

distal extension

proximal and distal portion

proximal tomes

Question 19

in the secretory stage ribosomes help

which are packeages into

These contain

and are then secrected via

the inital layer is laid down on the..

and is minerlised

meaning that this layer of enamel does not contain

Answer 19

synthesis proteins

secrectory granules in the Golgicomplex

enamel proteins

tomes process

mantel dentin (initial dentin)

immediately

enamel rods

Question 20

As more enamel matrix is layed down ameloblasts move

The tomes process develops

This extention is….

and it keeps…

The tomes process resposible for

Answer 20

Away from the enamel

And extention from the proximal portion

distal tomes process

elongating as more enamel matrix is secrected

Rod and interrod enamel

Question 21

enamel matrix is sectrected from two sites of the tomes process

The enamel matrix sectrected by the proximal portion……. the enamel matrix sectrected by the distal portion of the tomes process

The enamel matrix secrected by the distal of the tomes process forms

That which surrounds the rod is called

as the enamel matrix contiues to be sectrected , the distal portion of the tomes process…..but gradually becomes….and get ….. out of existance

Once this happens there is a thin space at this junction between the….. filed with

Answer 21

the proximal portion of the tomes process and the distal portion of the tomes process

surrounds/ encircles

Enamel rod

Interrod enamel

Elongates/ thinner/ squeezed

Rod and interod / inorganic material

Question 22

The distal portion of the tomes process helps form….

Once the tomes process has disappeared the ameloblasts

meaning the last bit of enamel formed has

So the final enamel is composed of

Answer 22

enamel sheath between the enal rods and interenamel rods

assembles how it was initally

No enamel rods

enamel with rods and interods squeezed between two layers of enamel without rods

Question 23

Maturation phase of amelogenesis consitis of

Answer 23

Transitionl phase and mauration prop

Question 24

Tr