Tooth Eruption Flashcards
Eruption is part of __________________
tooth development
thickening of the epithelium through cell division determines the position where a row of teeth will form
primary epithelial band
further epithelial thickening and bifurcation into dental and vestibular lamina
dental and vestibular laminae
Invagination of DL determines the locations where individual teeth will
develop. Invagination of DL is stimulated by ectomesenchymal cells
expressing Pax9. Tooth type is also determined at this stage, according to
other transcription factors expressed in the ectomesenchyme
bud stage
Beginning of tooth morphogenesis and histodifferentiation processes. The
DL forms the enamel organ (EO). Cells of the EO will differentiate into inner
and outer enamel epithelia, stellate reticulum and stratum intermedium.
EMC will differentiate into dental follicle and dental papilla
cap stage
Extension of cervical loop. Enamel knot(s) determine formation of cusps.
bell stage
appositional deposition of dentin and enamel
late bell stage
Cervical loop transforms into Hertwig epithelial root sheet (HERS), which
becomes an organizing center of root formation. Dentin is deposited
alongside HERS. The HERS fragments and cells of dental follicle deposit
cementum and form PDL. Once the length of a root is complete, HERS
changes its direction inward leading to narrowing of the apical foramen
root formation
primary oral cavity is lined with what
ectoderm derived epithelium
beneath epithelium, there is what
ectomesenchyme
areas of the oral epithelium where dentition will form thicken to form the ________________
primary epithelial band
the primary epithelial band splits into what
dental lamina and vestibular lamina
dental lamina will develop into buds where what will form
individual teeth
where a tooth will form there is invagination of the dental lamina into a ________ and condensation of _____________ around it
bud
ectomesenchyme
what stage is the type of tooth and position determined
bud stage
the ________ forms from the dental lamina and starts to develop different cell layers
enamel
what stage does enamel form in
cap stage
what cell layers develop from the enamel/dental lamina
outer enamel epithelium
stratum reticulum
inner enamel epithelium
stratum intermedium
cells in the ectomesenchyme form the _____________ and the ______________
dental follicle and the dental papilla
when do the dental follicle and dental papilla form
cap stage
cells continue to differentiate and the stratum intermedium is evident in this stage
bell stage
where the outer enamel epithelium joins the inner enamel epithelium and extends apically
cervical loop
when does the cervical loop form
bell stage
the enamel knots formed in the bell stage stimulate growth of ________
cusps
the outer cells of the dental papilla become ___________ that secrete dentin
odontoblasts
when is dentin secreted
apposition stage
cells in the inner enamel epithelium become __________ that secrete enamel
ameloblasts
when is enamel secreted from ameloblasts
apposition stage
once crown formation is complete, the developing tooth does what
begins to erupt
while the tooth erupts, what is still forming
roots
what forms the hertwig’s epithelial root sheath
cervical loop
what does HERS guide
root formation
when do primary teeth start developing
6th week of prenatal development
when do primary teeth start erupting
6 months old
when do permanent teeth start developing
14th week of prenatal development
when do permanent teeth begin erupting
6 years old
what teeth are nonsuccedaneous
first, second, and third molars
develop from successional dental lamina lingual to developing primary teeth
succedaneous teeth
develop from posterior extension of dental lamina called the accessional dental lamina
nonsuccedaneous teeth
in late cap/early bell stage of the primary tooth, the lingual portion of the dental lamina becomes the what
successional lamina