complete the process
stomadeum –> –>
stomadeum –> oral epithelium –> dental lamina
what are epithileal-mesenchymal interactions?
- dental lamina secretes growth factor
- induces expression of TF
- leads to differentiation of mesenchyme
what signifies the start of odontogenesis?
appearance of dental lamina
the tooth is formed from the combo of? (2)
which arch?
- NC cells
- mandibular epithelium
1st arch
finish the process
oral epithelium –> –> –> –>
oral epithelium –> dental lamina –> bud –> cap –> stage
the differentiation of _____ _____ occurs in the bud stage
when does the bud form?
what tethers the bud?
- dental lamina
- bud forms after epithileal incursion into mesenchyme
- lateral lamina (part of dental lamina) tethers the bud
describe asynchronous tooth development
1st: anterior mandible
2nd: anterior maxilla
moves anterior to posterior in both jaws
what are the abnormalities in the bud stage?
- microdontia
- macrodontia
what are the 3 enamel layers in the cap stage
- outer enamel epithelium
- stellate reticulum
- inner enamel reticulum
tooth germ consists of? (3)
- enamel organ
- dental papilla
- dental follicle
dental follicle consists of?
- cementum
- PDL
- alveolar bone
dental follicle is formed by
dental papilla
what makes up the cervical loop?
- outer enamel epithelium
- inner enamel epithelium
finish:***
IEE –> –>
IEE –> ameloblasts –> enamel
where is enamel laid down? what direction does it move?
where is dentin made? where does it move?
enamel
- laid down on cusp
- moves away from the DEJ
dentin
- made ar crown
- moves inward
finish
dental papilla –> –>
dental papilla –> odontoblasts –> dentin
what do the peripheal cells of the dental papilla face? what do the inner cells form?
periphreal: face the IEE
inner cells: form the pulp
inner cells of dental follicle form?
outer cells form?
inner –> cementoblasts –> cementum
outer –> PDL
- contribute to alveolar bone formation
what are the abnormalities in the cap stage?
- dens in dente
- fusion
- gemination
what is morphodifferentiation? histodifferentiation?
morpho: enamel organ takes shape of incisor, canine, molar
histo: ameloblasts and odontoblasts acquire phenotype
what happens in HERS?
- joining of IEE and OEE
- initiates root formation
what is the 1st important thing that happens in the bell stage?
- dental lamina disintegrates, separating tooth from oral epithelium
- tooth continues development
- before tooth can function, it reestablishes a connection with the oral epithelium by formation of the junctional epithelium
- posteriormost extent of dental lamina does not disintegrate, but elongates posteriorly. gives rise to 12 buds, the precursors to permanent molars
2nd important thing that happens in bell stage?>
crown pattern and number of cusps on tooth is established following folding of IEE
all tooth structures are _____ in origin except ____
all tooth structures are neural crest cell in origin except enamel
