QUIZ 3 Dentin Pulp Complex I Flashcards
dentin is the main ___ material of the tooth
structural
the structure of the dentin is directly linked to what?
its primary function of supporting tooth loading
briefly describe enamel, dentin, and pulp
- enamel
- mineralized protective component
- dentin
- mineralized structural component
- pulp
- main cellular component
dentin is highly analogous to ___, but slightly different composition and highly different anatomy
bone
the crown is covered by ___, and the root is covered by ___
- enamel
- cementum
dentin is ___% inorganic material, ___% organic material, and ___% water
70%, 20%, 10%
hydroxyapatite makes up the ___ component of dentin
inorganic material
what is the formula for hydroxyapatite, and how many molecules of HA are in each crystal unit cell?
Ca5(PO4)3(OH)
2 per crystal unit cell
HA is effectively a ___ ___ crystal
calcium phosphate
fluoride can replace the ___ in hydroxyapatite, creating ___
- OH
- fluoroapatite
besides fluoride, what else can replace the OH in hydroxyapatite in dentin?
zinc, magnesium, and others
in dentin, HA crystals are what shape?
flattened rectangular plates
what are the dimensions of HA in dentin?
- 60-70 nm long
- 20-30 nm wide
- 3-4 nm thick
dentin is somewhat harder than ___. what are the knoop numbers for dentin, enamel, and bone?
- bone
- knoop numbers:
- dentin - 68
- enamel - 343
- cortical bone - 50
what is the composition of the organic material component of dentin?
- 90% collagen
- mostly I, some III and V
- 10% non-collagenous proteins
describe the collagen component of the organic component of dentin
- 90%
- mostly collagen I, some III and V
- fibrillar collagen scaffold upon which HA crystals are laid down
what are the 5 non-collagenous proteins that dentin has in common with bone?
- bone sialoprotein (BSP)
- osteopontin (OP)
- osteocalcin (OC)
- osteonectin (ON)
- matrix extracellular phosphoglycoprotein
what are the 2 main dentin specific non-collagenous proteins?
- dentin matrix protein-1 (DMP-1)
- dentin sialophosphoprotein (DSPP)
- *still found in bone, but only trace amounts
DSPP can be further cleaved into what 3 functional proteins?
- dentin sialoprotein (DSP)
- dentin phosphoprotein (DPP)
- dentin glycoprotein (DG)
DSPP is cleaved rapidly by what enzyme?
BMP-1
describe DSP
- proteoglycan
- expressed in dentinal tubules
- may act to prevent mineralization
- similar to DMP-1
describe DGP
- glycoprotein
- role in biomineralization?
- unknown function
describe DPP
- binds lots of calcium, initiates HA formation
- attached to collagen
- not thought to be glycosylated
DSP comes from which end of DSPP?
N terminus



