Enamel Flashcards
enamel is the only __________ tissue
acellular
T/F: enamel can remodel and repair
false
what is the composition of enamel
96% hydroxyapatite
what is the major function of enamel
mastication
what is the basic building block of enamel
rod
enamel rods run from where to where
DEJ to enamel surface
these are thin proteinaceous layers, enveloping enamel rods
rod sheath
seen as profound lines in ground enamel sections
stria of retzius
what might stria of retzius be related to
metabolic changes
the most accentuated stria of retzius is known as what
neonatal line
what structures are found at the DEJ
enamel tufts, enamel lamellae, and enamel spindles
enamel tufts contain less _________ and more __________
less mineral and more organic material
enamel tufts play a role in what
toughening enamel
enamel tufts serve as anchors of _______ to ________
enamel to dentin
enamel tufts are rich in ___________
proteins
enamel lamellae contain more ___________ and less ___________
more organics and less minerals
where does the enamel lamellae originate
DEJ
enamel lamellae play a role in doing what
toughening enamel
when are enamel spindles formed
at presecretory stage
enamel spindles are continuous with what
dentinal tubules
enamel spindles contain __________ crossing over the DEJ
odontoblasts
scalloping of the dentin surface __________ the area of interface between enamel and dentin
increases
fluorapatite is _______ soluble than hydroxyapatite
less
fluorapatite is more stable at a _____ pH
low
process of enamel formation
amelogenesis
differentiation of cells of enamel organ and dental papilla lead to what
appositional growth phase
cells of inner enamel epithelium, cap stage
morphogenetic stage
bell stage, preameloblast
histodifferentiation
lacks Tome’s process, bell stage
presecretory-initial secretory stage
well defined Tome’s process, enamel thickness deposited, bell stage
secretory stage
removal of organic material, thickening of mineral crystals
maturation stage
cells differentiate, develop secretory phenotype
preameloblasts
when does the beginning of the basal lamina degradation start
preameloblast stage
degredation of basal lamina
presecretory ameloblasts
in the presecretory ameloblast stage cells secrete initial _________ enamel layer
rodless
secrete the bulk of enamel
secretory ameloblasts
what develop’s Tome’s process
secretory ameloblasts
crystals are oriented ____________ to the surfaces from which enamel rod is secreted
perpendicular
major ECM protein
amelogenin
mutations in amelogenin lead to what
amelogenesis imperfecta
amelogenesis imperfecta is more common in who
men
when does mineral thickening begin
secretory stage
crystal sizes increase during what
enamel maturation