early tooth development

Question 1

which Branchial arch gives rise to the maxillary and mandibular process and hence your teeth?

Answer 1

1st branchial arch

Question 2

what 2 tissues to dental tissues originate from? and what are THEIR origins?

Answer 2

epithelium-ectoderm orignin and mesenchyme-from cranial neural crest cells

Question 3

what dental tissue comes from the ectoderm epithelia and what comes from the mesencyme cells

Answer 3

epithelium= only enamel 
mesenchyme= dental pulp,dentin, periodontal ligament =alveolar bone socket, cementum

Question 4

what happens to cranial neural crest cells developed in the brain region?

Answer 4

they migrate in ‘streams’ down the sides of the embryo into the pharyngeal arches

Question 5

what does the fronto-nasal process develop into on your face?

Answer 5

the forehead

Question 6

Neural crest cells transition from epithelial cells to ______? known as EMT

Answer 6

to mesenchyme = ectomesenchyme

EMT= epithelial to mesenchyme transition

Question 7

cranial neural crest cells CNCCs are what type of stem cells?

Answer 7

multipotent stem cells

Question 8

list the cells that arise from ectomesenchymal cells?

Answer 8

fibroblasts, chondroblasts, odontoblasts, cementoblasts, osteoblasts

Question 9

what cells secrete dentin?

Answer 9

odontoblasts

Question 10

what cells secrete cementum?

Answer 10

cementoblasts

Question 11

CNCCs give rise to melanoblasts, schwann cells and neuroblasts. what do neuroblasts give rise to ?

Answer 11

sensory neurone, motor neurone and sympathetic neurone

Question 12

what is Treacher-Collins syndrome due to? and what is the general effect of it?

Answer 12

due to lack of NCCs

leads to defects in structures that develop from the first 2 branchial arches ie teeth and ears

Question 13

all upper teeth except _____ develop from oral side of maxilla. where do these develop from?

Answer 13

upper incisors

develop from oral side of fronto-nasal process, FNP

Question 14

what does the ‘initiation’ phase of early tooth development consist of?

Answer 14

a primary epithelial band forms along the oral side of the maxilla/mandible= thickened band of epi

Question 15

what 2 subdivisions does the epithelial band give rise to ?

Answer 15

lingual-dental lamina and buccal-vestibular lamina(space bet. teeth and lips or cheek)

Question 16

what happens to the dental lamina after it forms from the primary epithelial band?

Answer 16

it grows and a series of swellings develop on it to mark position of teeth ‘dental placodes’

Question 17

the disease from a PAX-9 mutation has what effect on tooth develpment?

Answer 17

tooth dev. fails at bud stage as mesenchyme cant condense.
cap stage cant be reached
leads to lots of teeth missing