tooth development Flashcards
(24 cards)
where does the ectomesenchyme come from?
neural crest
what is the first stage of the ectoderm portion of teeth?
the dental lamina
what germ layer(s) is/are teeth derived from?
ectoderm and ectomesenchyme (neural crest)
where do the buds of permanent teeth grow relative to primary teeth?
ligually, although permanent molars are posterior
what is the name for the buds of permanent teeth?
successional lamina
What other lamina grow besides the dental and successional lamina?
vestibular lamina; forms the vestibule
what is the bud stage?
the initial proliferation between the oral epithelium and the surrounding mesenchyme occurs
between the mesenchyme and the epithelium, which is shaped like a bud?
the oral epithelium
what does the oral epithelial layer become?
the enamel
when does the bud stage become the cap stage?
when the epithelial bud becomes concave
the mesenchymal layer that surrounds the epithelial bud layer is called?
the dental papilla
what layer surrounds the dental papilla?
the dental follicle?
what structures are seen in the cap stage?
dental papilla
enamel organ
dental follicle
the dental papilla is a precursor what what tooth structure?
the dentin and pulp
the dental follicle is a precursor what what tooth structure?
cementum, PDL and surrounding alveolar bone
which are formed from the neural crest mesenchyme?
enamel
dentin
cementum
dentin and cementum,
both the dental papilla and follicle are from the neural crest
what are two characteristics of the bell stage?
1) morphodifferentiation: the tooth structure is defined by the inner enamel epithelium and dental
2) the differentiation of the inner epithelial layer into ameloblasts
(cytodifferentiation also occurs)
what structure lies above the ameloblasts?
stratum intermedium, plays a role in the mineralization of enamel
in the bell stage, what makes up the enamel organ from out to in?
outer enamel epithelium
stellate reticulum (kinda all over the place)
stratum intermedium
inner enamel epithelium
what is the cervical loop?
the place where the inner and outer enamel epithelium meet, will eventually become the cervix
what is cytodifferentiation
the differentiation of the dental papilla into odontoblasts and enamel organ into ameloblasts
if the epithelial and mesenchymal layers are separated, can they still form teeth?
no, each layer is somewhat dependant on each other
which layer is giving the instructions?
in the beginning the epithelial layer gives the instructions, then later the mesenchyme takes charge
what is the trigger for odontoblast differentiation?
diffusible molecules or
cell-cell contact
cell-cell contact
epithelial processes penetrate the basal lamina and cause differentiation
