dentin
70% inorganic
Avascular
imbrication lines of von Ebner and contour lines of Owen are a number of adjoining parallel imbrication (shows disturbance)
calcium hydroxyapatite - formula of Ca10(PO4)6(OH)2
makes up the bulk of the tooth and protects the pulp
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Dentin Matrix Maturation
hydroxyapatite crystals form as globules in the collagen fibers of the predentin
new areas of mineralization occur as globules form in the partially mineralized predentin during the secondary mineralization phase
globular dentin
primary and secondary mineralization have occurred with complete crystalline fusion
interglobular dentin
only primary mineralization
darker arclike areas in a microscopic section of dentin
only primary mineralization has occurred within the predentin, and the globules of dentin do not fuse completely
Dentin Nutrition
tissue fluid in the dentinal tubules that originally traveled from the blood vessels located in the pulp
dentinal tubules
contain odontoblastic processes, dentinal fluid, and myelinated sensory axon
Dentinal Tubules Curvature
primary - overall tubule course over time (S shaped)
secondary - delicate curves in the primary curvature, reflecting the smaller daily changes in odontoblast direction
Dental papilla
Makes dentin and pulp
Odontoblasts
In pulp not dentin
Have extensions in dentin
Peritubular dentin
Most/highly mineralized
Wall of tubules
Intertubular dentin
Highly mineralized
Between tubules
Mantle dentin
First dentin formed
Outermost layer near dentinoenamel junction underneath enamel
Circumpulpal Dentin
Dentin formed after mantle dentin
Around pulp
bulk of the dentin
Layer around outer pupal wall
Primary dentin
regular pattern of tubules
formed in a tooth before the completion of the apical foramen
Secondary dentin
Formed after apical foramen and throughout life
Tertiary Dentin
reparative dentin
forms underneath the exposed dentinal tubules along the outer pulpal wall
sclerotic dentin
found in association with the chronic injury of caries and is noted in increased amounts as the tooth ages
dentinal hypersensitivity
open dentinal tubules may be painful for the patient
Tomes granular layer
underneath cementum
Central cells of dental papilla
Form pulp
Pulp tissue
sensory, nutritive, and protective properties
shape of pulp is similar to shape of tooth - cusps
Pulp chamber
coronal pulp
radicular pulp - on roots
Pulp horns
Apex of coronal pulp
Only on posterior teeth
Recede with age
Accessory canals
extra openings from the pulp to the periodontal ligament
form when HERS encounters blood vessel
Pulp zones
odontoblastic layer - lines outer pulpal wall and many odontoblastic cell bodies
cell free zone - nerve and capillary plexus
cell rich zone - increase density of cells
pulpal core - center of pulp chamber that has many cells and extensive vascular supply
Pulpits
Inflammation from mechanical or trauma injury
irreversible is done by root canal - lingering and random pain
Pulp
Odontoblasts cell bodies are in pulp but have extensions into dentin
Contains dental pulp stem cells
Two nerve types - myelinated and unmyelinated
Posterior Maxillary
PSA
Anterior Maxillary
Infraorbital artery
Mandibular
Inferior alveolar artery
Apical Foramen
Provides communication between pulp and PDL
Pulp stones
Mineralized masses of dentin in pulp