Dentin Pulp Complex I Flashcards
What is the function of a tooth?
Survive long-term cyclical loading
What is enamel?
What is dentin?
What is pulp?
Enamel - Mineralized protective component
Dentin - Mineralized structural component
Pulp - Main cellular component
What is dentin composed of?
70% - Inorgo
20% - Orgo
10% - H2O - Physiological fluid water
T/F - There is absolutely collagen (Mostly type I and some type III) in dentin.
TRUE
*Build on a collagen matrix
What is the inorgo material?
HYDROXYAPATITE
Like enamel crystals, but organized in a collagenous matrix
Ca10(PO4)6(OH)2 or Ca5(PO4)3(OH)2
Effectively, what is the HA in dentin?
Calcium phosphate crystals
F- can replace the OH, creating fluorapatite, also Zn and Mg, and others
T/F - Dentin is harder than bone, but weaker than enamel.
TRUE
Of dentin’s 20% organic material, what is the composition of it? Hint: 90:10
90% - Collagen (Mostly I, some III)
10% - Non-collagenous proteins
What are some non-collagenous proteins?
Dentin sialophosphoprotein (DSPP)
Dentin matrix protein-1 (DMP-1)
DSPP is cleaved further into what 3 proteins?
Dentin sialoprotein (DSP)
Dentin phosphoprotein (DPP)
Dentin glycoprotein (DG)
What cleaves DSPP?
BMP-1
Tell me about DSP.
Proteoglycan
Expressed in dentinal tubules
May act to PREVENT mineralization
Similar to DMP-1
Tell me about DGP.
Glycoprotein
Unknown fx
Tell me about DPP.
Only protein
Binds Ca2+, initiates HA formation
Attached to collagen
Defects in DSPP can cause what two malformations of dentin?
Dentinogenesis imperfecta II and III
What is dentinogenesis imperfecta type I?
RESULTS FROM OSTEOGENESIS IMPERFECTA (This is a defect in collagen I)
Pulp chambers filled with abnormal dentin
What is dentinogenesis imperfecta type II?
NOT ASSOCIATED WITH OSTEOGENESIS IMPERFECTA (This is a DSPP defect)
Pulp chambers fill with abnormal dentin
What is dentinogenesis imperfecta type III?
Enlarged pulp chambers, HYPOmineralization
Probably DSPP expression failure
T/F - All types of dentinogenesis imperfecta results in non-vital teeth.
TRUE
Dentin is made by what cells?
ODONTOBLASTS
-Line the pulp chamber
-Mesenchymal origin
—From dental papilla
—Ectomesenchymal origin
T/F - Odontoblasts are polarized cells which extend cellular projections into the dentin thru tubules.
TRUE
T/F - Dentin-pulp complex arises from dental papilla.
TRUE