development of tooth and its supporting tissues

Question 1

at what day of development the primary epithelial band develops?

Answer 1

37 days of development

Question 2

what does the primary epithelial band does?

Answer 2

it gives rise to two subdivisions that ingrow into the ectomesenchyme which are the dental lamina and vestibule lamina.

Question 3

what are the three stages of tooth development?

Answer 3

cap stage, bud stage and bell stage

Question 4

important growth factor/ genes names of oral epithelium ?

Answer 4

BMP ( bone morphogenic protein) 
SHH ( sonic hedgehog) 
FGF (fibroblast growth factor ) 
WNT ( wigless related integration) 
TNF ( tumorous necrosis factor )

Question 5

genes of ectomesenchyme?

Answer 5

BMP ( Bome morphogenic protein

ACTIVIN

Question 6

what does the vestibule lamina makes?

Answer 6

the vestibule

Question 7

what is the bud stage?

Answer 7

the first epithelial incursion into the ectomesenchymec ells

Question 8

what happens in the cap stage of development ?

Answer 8

at this stage u can see the formative tissues of the tooth which are 
the enamel organ ( the cap part) 
dental papilla 
dental follicle 
lateral

Question 9

the rudimentary things in cap stage are ?

Answer 9

enamel cord
enamel niche
enamel knot

Question 10

what does enamel knot makes?

Answer 10

cusp tip of the teeth

Question 11

tell the formation of stellate reticulum ?

Answer 11

the cells of the enamel organ have abundant glycosaminoglycans in the extracellular compartment between the epithelial cells
the glycosaminoglycans are hydrophilic and attarct water which increase the volume of extracellular compartment of enamel organ, the cells are forced apart but are still intact through the desmosomes and thus are star shaped and called stellate reticulum.

Question 12

what happens at bell stage?

Answer 12

by the start of this stage shape of the tooth has already been decided
the cells bordering the dental lamina are columnar and makes up the inner enamel epithelium

Question 13

the point at which the inner and outer enamel epithelium meet at the rim of the enamel organ is called

Answer 13

zone of reflection

Question 14

what makes the stratum intermediate ?

Answer 14

the cells between inner enamel epithelium and stellate reticulum differentiate to make the stratum intermediate.

Question 15

the two other important things happening in the bell stage are?

Answer 15

the dental lamina joins the tooth germ to 4.the oral epithelium fragments eventually separating the tooth from the oral epithelium
and then the inner enamel epithelium completes its folding to allow us to recognize the shape of the future crown

Question 16

the fragments of dental lamina (series/ seres ) that presist can cause what diseases in the tooth?

Answer 16

1. eruption cyst
2. delay eruption
3. odontome
4. supernumeray teeth

Question 17

first the dentin and enamel deposits where?

Answer 17

the cusp tip of the teeth

Question 18

from what part the permanent teeth are made

Answer 18

dental lamina

Question 19

how are the molars made?

Answer 19

the dental lamina extends posteriorly into the ectomesenchyme into the oral epithelium, this backwards extension makes epithelium outgrowths that associated with ectomesenchyme makes the first second and third molars

Question 20

the entire primary dentition is initiated between?

Answer 20

6-8 weeks

Question 21

permnanent teeth are made between?

Answer 21

20 in utero and 10 months after birth

Question 22

the permanent molars?

Answer 22

20 in utero and 5 years (third molar)

Question 23

what is the origin of tooth germ?

Answer 23

ectoderm (ectomesenchyme)

Question 24

the tooth germ makes up the?

Answer 24

1. dental papilla
2. enamel organ
3. dental follicle

Question 25

what type of cells the dental papilla makes up?

Answer 25

odontoblast

undifferntiated mesenchymal fibroblast

Question 26

what does the enamel organ makes up?

Answer 26

1. cervical loop
2. outer enamel epithelium
3. stellate reticulum
4. startum intermedium
5. inner enamel epithelium

Question 27

what cells the dental follicle makes up?

Answer 27

1. cementoblast
2. fibroblast
3. osteoblast

Question 28

cervical loop makes up what?

Answer 28

HERS hertwigs rooth sheath

Question 29

inner enamel epithelium makes up?

Answer 29

ameloblasts

Question 30

hers make up?

Answer 30

root form