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35 Cards in this Set
- Front
- Back
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Stage 1 Dentinogenesis
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Lays down organic matrix (pre-dentin)
Thickest pre-dentin is formed at the beginning, near DEJ Formation always starts at the most coronal part |
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Stage 2 Dentinogenesis
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Mineralization of pre-dentin
Crystals get deposited along direction of collagen fibers |
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What two proteins play a role in initiation of the mineralization process
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Dentin Phosphophoryn Protein (DPP)
Dentin Sialoprotein (DSP) |
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How does calcium come in and get deposited in dentin?
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Ca++ diffuses from the bloodstream into the odontoblast, and then gets secreted out into the organic matrix
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calcoglobule
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Calficication piece by piece in an asterisk kind of way
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Characteristics of Dentin
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slightly yellow and darker in color than enamel
more raduiolucent than enamel more radiopaque than cementum A living tissue similar to bone HAP crystals are smaller than in enamel |
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Dentin makeup
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70% inorganic + 20% organic + 10% water
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Primary dentin
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makes up the bulk of the crown & root
Consists of Mantle, Circumpulpal, Interglobular, Tome's Granular Layer |
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Mantle Dentin
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thin, closest to the DEJ
does NOT contain the Phosphophoryn protein it’s less mineralized than Circumpulpal Dentin has branched Korff’s Reticular Fibers Has collagen fibers Stains with silver |
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Which type of dentin does NOT contain the Phosphophoryn protein
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Mantle Dentin
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Which type of dentin stains with silver
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Mantle Dentin
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Circumpulpal Dentin
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No Korff Fibers
Mostly collagen fibers contains the Phosphophoryn protein makes up most of Primary Dentin & all of Secondary Dentin |
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Which type of dentin makes up all of secondary dentin
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Circumpulpal dentin
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Interglobular Dentin
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Hypomineralized dentin
located in b/t Mantle & Circumpulpal dentin |
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Tomes Granular Layer
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hypomineralized, located near the CDJ and DEJ
When odontoblasts try to move into position towards DEJ, the odontoblastic process gets coiled up reducing amount of HAP present |
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Secondary Regular Dentin
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only gets deposited after primary dentin has finished completion of tooth formation
narrows the pulp chamber has fewer odontoblasts, fewer processes, fewer tubules when compared to primary dentin |
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Which areas of the pulp chamber have greater amounts of Secondary Regular Dentin
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Roof and floor and horns
Lateral walls have much less |
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Primary dentinal tubules vs Secondary dentinal tubules
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Wavy vs perpendicular to long axis of tooth
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Secondary Irregular Dentin
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AKA Tertiary Dentin
gets laid down at a local site only when there is a stimulus causes narrowing of the pulp forms very rapidly Includes Reactive and Reparative Dentin |
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Reactive Dentin
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Secondary Irregular Dentin
formed by pre-existing odontoblasts |
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What dentin is formed by pre-existing odontoblasts
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Reactive Dentin
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Reparative Dentin
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Secondary Irregular Dentin
formed by giving rise to NEW odontoblasts |
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What dentin is formed by giving rise to NEW odontoblasts
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Reparative Dentin
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Osteodentin
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When Secondary Irregular Dentin forms slowly
Resembles bone more regular in arrangement, less entrapment of cells |
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Sclerotic / Transparent Dentin
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pre-existing dentin
Modified by the addition by more HAP crystals see thru it like glass most mineralized resembles enamel Usually forms in roots of older people Offers protection |
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Which type of dentin is the most mineralized?
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Sclerotic Dentin
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Where is the odontoblastic process widest?
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Widest where it connects to the cell body
Tapers towards distal end |
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Intertubular Dentin
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makes up most of the dentin
has less fibers less mineralized |
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Peritubular Dentin
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makes up the outer wall of the dentinal tubule
more fibers more mineralized |
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Intratubular Dentin
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forms an organic sheath
surrounds the process within the inner wall of the dentinal tubule |
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What type of dentin makes up the outer wall of the dentinal tubule
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Peritubular Dentin
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What type of dentin makes up the inner wall of the dentinal tubule
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Intratubular Dentin
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Contour Lines of Owen
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equivalent to the Lines of Retzius in enamel
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Neonatal Lines
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transition between pre-natal and post-natal dentin
an exaggerated Contour Line of Owen |
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Von Ebner Lines
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equivalent to the Daily Incremental Lines in enamel
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