Dentin Flashcards
Calcium Hydroxyapatite %
Enamel > Dentin > Cementum (bone)
Radiolucent - Radiopaque
[dark] pulp - cementum - dentin - enamel [light]
Dentinogenesis
Dentin formation
- during apposition stage of TD
- growth throughout life of tooth
Predentin
Mesenchymal product
Odontoblasts -> type 1 collagen + phosphoprotien (acidic, attracts calcium)
Primary Dentogenesis
Calcospherules
Expansion + Fusion
Interglobular dentin
Secondary Dentinogenesis
Layered mineralization
Globular dentin
Interglobular Dentin
Not completely fused, less mineralized
Dentinal Tubules: contents
Dentinal fluid, afferent nerve axon
Dentinal Tubules: where
(thin) DEJ/CEJ - outer pulp wall (thick)
Dentinal Tubules: curvature
Primary = S-shape, over time Secondary = small, daily changes
Peritubular Dentin
In tubal walls
Highly mineralized
Interrubular Dentin
Between tubuals
Highly mineralized
Mantle Dentin
Outermost near DEJ
First formed
Circumpulpal Dentin
Around pulpal wall
Second formed
Primary Dentin
B4 apical foreman
More mineralized than secondary
Secondary Dentin
After apical foramen
Less mineralized than primary
Tertiary Dentin
Injury
Irregular
Sclerotic Dentin
Type of tertiary
Chronic injury, caries, attrition, abrasion, age
Odontoblastic peocesses die,
tubuals vacant
Smear Layer
When dentin is cut
Biofilm
Dentinal Hypersensitivity
When dentin is exposed
Imbrication lines of von Ebner
Incremental
“Tree rings”
(dentin)
Contour lines of Owen
Specific lines from disturbance
dentin
Tomes Granular Layer
@ DEJ
Less mineralized
Aging Dentin
Tubuals narrow
Reduced organelles
Less sensitivity
