Microsoft PowerPoint - 08 Dentin-Pulp Complex().ppt []

1.Illustrated Dental Embryology, Histology, and 1.Illustrated Dental Embryology, Histology, and Anatomy: Mary BathAnatomy: Mary Bath--Balogh, Margaret J. Balogh, Margaret J. Fehrenbach, 2nd Edition, Elsevier Saunders,2006 Fehrenbach, 2nd Edition, Elsevier Saunders,2006
2 E t ti l f O l Hi t l d E b l2 E t ti l f O l Hi t l d E b l AA2.Esstential of Oral Histology and Embryology2.Esstential of Oral Histology and Embryology----A A clinical approach: James K Avery, Denial J clinical approach: James K Avery, Denial J Chiego,Jr 3rd Edition, Elsevier Mosby, 2006 Chiego,Jr 3rd Edition, Elsevier Mosby, 2006
3.Ten Cate's Oral Histology: Development, 3.Ten Cate's Oral Histology: Development, Structure, and Function: Nanci Anatonio, 6th ed. Structure, and Function: Nanci Anatonio, 6th ed. Mosby, 2003 Mosby, 2003
SummarySummary
Dentin Dentin
•• OdontoblastOdontoblast •• 70% inorganic material ,20 % 70% inorganic material ,20 %
oraganic ,10 % wateroraganic ,10 % watero aga c , 0 % ateo aga c , 0 % ate •• The inorganic material is hydroxyapatiteThe inorganic material is hydroxyapatite •• Organic is 30% collagen (mainly Type I, Organic is 30% collagen (mainly Type I,
small amount of type III and V)small amount of type III and V)
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•• Dentinal TubuleDentinal Tubule •• Peritubular DentinPeritubular Dentin •• Sclerotic DentinSclerotic Dentin•• Sclerotic DentinSclerotic Dentin •• Intertubular DentinIntertubular Dentin •• Interglobular DentinInterglobular Dentin
Dentin ClassificationDentin Classification
•• Primary DentinPrimary Dentin
•• Reparative DentinReparative Dentin
Primary Dentin Primary Dentin
•• Major component of crown and root Major component of crown and root •• Mantle and circumpulpal dentin Mantle and circumpulpal dentin •• Mantle dentin is the first primary dentinMantle dentin is the first primary dentin•• Mantle dentin is the first primary dentin Mantle dentin is the first primary dentin •• Circumpulpal dentin direct underlies Circumpulpal dentin direct underlies
mantle dentin mantle dentin
Mantle Dentin Mantle Dentin
•• 150 um from DEJ150 um from DEJ--interglogular dentininterglogular dentin •• 4% mineralized 4% mineralized •• Composed of large(0 1Composed of large(0 1--0 2 um) collagen0 2 um) collagen•• Composed of large(0.1Composed of large(0.1 0.2 um) collagen 0.2 um) collagen
fiber fiber •• Integrates with enamel at DEJ Integrates with enamel at DEJ •• In the one of globular dentin centrally In the one of globular dentin centrally •• Interglobular dentin in the space Interglobular dentin in the space
Circumpulpal dentin Circumpulpal dentin
Secondary Dentin Secondary Dentin
•• Formation after crown loading Formation after crown loading •• Formation after root complete Formation after root complete •• Laid down as a continuation of primary Laid down as a continuation of primary p yp y
dentin dentin •• More in roof and floor of coronal pulp More in roof and floor of coronal pulp
chamber chamber •• Continued dentinal tubule from primary Continued dentinal tubule from primary
dentin dentin
Reparative dentin Reparative dentin
•• Tertiary DentinTertiary Dentin •• Formed by pulp stimulation and Formed by pulp stimulation and
odontoblast activationodontoblast activationodo tob ast act at oodo tob ast act at o •• Underlines the stimulated area Underlines the stimulated area •• Odontoblast ,fibroblast and blood cell can Odontoblast ,fibroblast and blood cell can
be found be found
•• Newly formed ,unmineralized matrixNewly formed ,unmineralized matrix •• At the border of pulpAt the border of pulp •• Mineralization occurred on predentinMineralization occurred on predentin ––•• Mineralization occurred on predentin Mineralization occurred on predentin
dentin junction dentin junction •• 4um /day during primary dentition 4um /day during primary dentition
formation formation •• 11--1.5 um /day after function1.5 um /day after function
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Dentinal tubule Dentinal tubule
•• Odontoblast process insideOdontoblast process inside •• From Pulp to DEJ From Pulp to DEJ •• ØØ1um in outer area1um in outer areaØØ1um in outer area 1um in outer area •• ØØ33--4um in pulp border4um in pulp border •• Number ratio DEJ: pulp border=4: 1Number ratio DEJ: pulp border=4: 1 •• 3000030000--50000 tubules /mm50000 tubules /mm22
Intratubular dentin Intratubular dentin
dentinal tubulesdentinal tubules •• Sclerotic dentin (transparent dentin ) Sclerotic dentin (transparent dentin )
usually was found overlaying the pulp usually was found overlaying the pulp horn horn
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Intertubular dentin Intertubular dentin
•• Type I collagen and Hydroxyapatite Type I collagen and Hydroxyapatite •• Main body of dentin between or around Main body of dentin between or around
dentinal tubules dentinal tubules dentinal tubules dentinal tubules
Incremental line Incremental line
•• Imbrication line , line of von Eber Imbrication line , line of von Eber •• 20 um line / 5 days 20 um line / 5 days •• Prenatal dentin and postnatal dentinPrenatal dentin and postnatal dentin•• Prenatal dentin and postnatal dentin Prenatal dentin and postnatal dentin
seperated by neonatal lineseperated by neonatal line •• 4 um /day in primary dentin 4 um /day in primary dentin
Granular layer Granular layer
•• A granular layer underlying the cementum A granular layer underlying the cementum •• Granular layer of TomesGranular layer of Tomes •• Coalescing and looping of the end ofCoalescing and looping of the end of•• Coalescing and looping of the end of Coalescing and looping of the end of
dentinal tubulesdentinal tubules
Dental pulp Dental pulp
•• Soft connective tissue located in the Soft connective tissue located in the center of toothcenter of tooth
•• Cells eg. OdontoblastCells eg. OdontoblastCe s eg Odo tob astCe s eg Odo tob ast •• Collagen fiber and ground substanceCollagen fiber and ground substance •• Blood vesselBlood vessel •• Lymph vesselLymph vessel •• NerveNerve
Anatomy of PulpAnatomy of Pulp
•• 52 pulps , 20 in primary teeth ,32 in 52 pulps , 20 in primary teeth ,32 in permanent tooth permanent tooth
•• 0.38ml in permanent 0.38ml in permanent 0 38 pe a e t0 38 pe a e t •• 0.2 ml in primary 0.2 ml in primary •• Coronal pulpCoronal pulp •• Radicular pulp Radicular pulp •• Apical foramina and accessory canals Apical foramina and accessory canals
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Coronal pulpCoronal pulp
•• Crown of the toothCrown of the tooth •• Follow the contour of crown Follow the contour of crown •• Numbers of pulp horns depends on cuspsNumbers of pulp horns depends on cusps•• Numbers of pulp horns depends on cuspsNumbers of pulp horns depends on cusps
Radicular Pulp Radicular Pulp
•• Extend from cervical region to apexExtend from cervical region to apex •• Apical canal may become narrowed by Apical canal may become narrowed by
cementum deposition cementum deposition cementum deposition cementum deposition
Apical foraminaApical foramina
•• 0.30.3--0.6mm 0.6mm •• Center in newly formed apexCenter in newly formed apex •• Eccentrically located by ageEccentrically located by age•• Eccentrically located by age Eccentrically located by age •• 33% accessory canals around the apex 33% accessory canals around the apex
Accessory canalsAccessory canals
Histology of pulp Histology of pulp
•• Odontogenic zone Odontogenic zone odontoblast odontoblast cell free zone (Zone of Weil Weilcell free zone (Zone of Weil Weil’’s basals basalcell free zone (Zone of Weil ,Weilcell free zone (Zone of Weil ,Weil s basal s basal layer)layer) cell rich one cell rich one
•• Paritetal layer of nervesParitetal layer of nerves
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Odontoblast Odontoblast
•• Small and oval => columnarSmall and oval => columnar •• Process to dentinsProcess to dentins •• Tall columnar cell in pulp horn (35um inTall columnar cell in pulp horn (35um in•• Tall columnar cell in pulp horn (35um in Tall columnar cell in pulp horn (35um in
length), getting flatter in apexlength), getting flatter in apex
Junction complex Junction complex
•• Tight junction Tight junction –– maintain position maintain position •• Gap Junction Gap Junction –– communication of cell communication of cell
electrical impulse electrical impulse e ect ca pu see ect ca pu se •• Intermediate JunctionIntermediate Junction
FibroblastFibroblast
•• Collagen production Collagen production •• Large oval nucleus Large oval nucleus •• Spindle with few organelles by agingSpindle with few organelles by aging•• Spindle with few organelles by aging Spindle with few organelles by aging
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•• SchwannSchwann’’s cell s cell •• Endothelial cellEndothelial cell •• Undifferentiated cellsUndifferentiated cells•• Undifferentiated cells Undifferentiated cells •• MarcrophageMarcrophage •• Lymphocyte Lymphocyte •• WBCWBC •• RBCRBC
Ground Substance Ground Substance
•• Type I and Type III collagen Type I and Type III collagen •• Type I was produced by odontoblasts , Type I was produced by odontoblasts , •• Type III was produced by fibroblastsType III was produced by fibroblasts•• Type III was produced by fibroblastsType III was produced by fibroblasts •• Elastin fiber along with blood vessels Elastin fiber along with blood vessels •• Fibronectin Fibronectin
VacularityVacularity
•• Blood flow and blood pressure are higher Blood flow and blood pressure are higher •• 5050--100um for arteries 100um for arteries •• Precapillaries 8Precapillaries 8--12um12um•• Precapillaries 8Precapillaries 8 12um 12um •• Capillary 8Capillary 8--10 um 10 um
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NervesNerves
•• 350350--700 myelinated axons and 1000700 myelinated axons and 1000--2000 2000 nonmyelinated axons entering the apexnonmyelinated axons entering the apex
•• Nerve plexus of Raschkow Nerve plexus of Raschkow Nerve plexus of Raschkow Nerve plexus of Raschkow •• Pass to odontogenic zone Pass to odontogenic zone •• Terminated among odontoblasts Terminated among odontoblasts
Pain and DentinPain and Dentin--Pulp Complex Pulp Complex
•• Direct innervation Direct innervation •• Transduction theory Transduction theory •• Hydrodynamic theoryHydrodynamic theory•• Hydrodynamic theoryHydrodynamic theory
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