Development of the Tooth and its supporting tissue Flashcards
all organs develop from
epithelium and
intracrine
produce in nuclesus and goes right back in without leaving the cell
induction influence is in the epithelial layer: influencing underlying mesenchyme to become a tooth
.
Cranial neural crest and nerves form:
- ganglia and nerves
- adrenal medulla
- ectomesenchyme of bones and teeth (all but enamel)
six stage of crown development
- initiation
- bud
- cap
- bell
- apposition
- maturation
what is happening during initiation stage
induction
what is happening during bud stage
proliferation
what is happening during cap stage
proliferation, differentiation, morphogenesis
what is happening during bell stage
proliferation, differentiation, morphogenesis
what is happening during apposition stage
induction and proliferation
what is happening during maturation stage
maturation
in bud stage, each bud is a precursor of
enamel organ for each deciduous tooth
In bud stage, what stimulates the mesenchyme to transcription factors
BMP-4, Fgf-8, Lef-1
in bud stage, there are ___ locations along each dental lamina, ____ of epithelium produces buds
ten, proliferation
in initiation stage, what stimulates pre-dental ectoderm to produce Fgf-8
Lef-1
in initiation stage, what induces mesenchyme to express Pax-9 and Msx-1
Fgf-1
in initiation stage, what inhibits Fgf-8
BMP-2 and 4
what happens in Cap stage?
ectomesenchyme cells condense around developing cap
in cap stage, what becomes the dental papilla and dental sac?
ectomesenchyme
tooth germ = ?
enamel organ, dental papilla, dental sac
successional dental lamina forms on____ of dental lamina
lingual side
the cap stage is
unequal proliferation of bud cells cause a cap to form
bell stage is
continued differntiation of enamelorgan produces four distinctlayer with different function
in bellstage, how many layers are there
4
what are the four layers of bell stage
- outer enamel epithelium
- stellate reticulum
- stratum intermedium
- inner enamel epithelium
in the bell stage, what is the cervical loop consist of
junction of OEE and IEE
in the bell stage, what does the dental papilla cells continue to proliferate into:
outer dental papilla cells
inner dental papilla cells
in the bell stage, what does the dental sac cells develop into later?
periodontal tissues
role of outer enamel epithelium
protective barrier for enamel organ
role of stellate reticulum
support enamel production
role of stratum intermedium
supports enamel mineralization -alkaline phasphatase
role of inner enamel epithelium
differentiate into ameloblasts
what is happening in the apposition stage
organic matrix ofenamel and dentin are laid down foloowed by initial calcification
in apposition stage the IEE differentiate into__1___, the -
preameloblasts
preameloblast induce ____ cells too differentiate into preodontoblast
dental papilla
preodontoblasts continue to differentiating into
odontoblast
in the apposition stage, the DEJ forms after
disintegration of basement membrane
what is prismless enamel formed by
early secretory ameloblast
enamel prisms are formed by
Tomes processes of late secretory ameloblast
in apposition stage, predentin induces differentiation of
preameloblasts into ameloblasts
in apposition stage, ameloblastbegin secreting enamel matrix whcih immediately califies to ___ of full mineralization
25%
what are the seven stages of the ameloblasts
- inner enamel epithelial cell
- preameloblast (cell reverses polarity)
- Initial secretory ameloblast (no tomes process)
- secretory ameloblast (tomes process)
- Smooth-ened maturation ameloblast (remove of protein/h20
- ruffled ended maturation ameloblast -intro inorganic material
- protective ameloblast- enamel cuticle
