Pulp

Dental Pulp for 1st BDS

1. Pulp
Dr.Smitha Rao

2. Pulp
Mesenchymeconnectivetissue
thatoccupiespulpcavityinthe
centralpartoftheteeth
Surroundedbydentinonallsides
exceptattheapicalforamen&
accessorycanalopenings

4. Pulp tissue removed during
endodontic therapy by a size 20
broach file

5. Pulp
32(permanent)+20(primary)=
52 Pulp organs
Total volumes of perm. teeth pulp organs =
0.38 cc
Mean volume of a single adult human pulp =
0.02 cc
Molarpulpsare3-4timeslargerthan
incisorpulps

6. DEVELOPMENT
Formed by dental papilla.
Odontoblasts –neural crest origin (ectodermal).
Other pulpal cells -mesenchymal origin.
Immature dendritic cells appear in and around the
odontoblastic layer at early stage.
First layer of dentin deposited-dental papilla
becomes dental pulp.
Numerous fibroblasts-remain closely packed, are
stellate shaped with large nucleus and little
cytoplasm and lay down fine collagen fibres.

7. DEVELOPMENT
Developing pulp has high GAG content.
Chondroitin sulphate is higher with little hyaluronan,
while opposite is true for mature pulp.
Enamel organ extends as HERS and determines final
morphology of the space (pulp chamber and root canals).
Once full length of roots is established, the developmental
stage of dental pulp can be considered complete.

8. Anatomy:
pulp
Coronal pulp
Radicular pulp

9. Coronal pulp
Has6surfaces
Haspulphornswhichareprotrusions
thatextendintothecuspsofeachcrown
Numberdependsonthecuspalnumber
Pulpbecomessmallerwithage

11. Radicular pulp
Extendsfromthecervicalregionofthe
crowntotherootapex
Anteriorteeth-single
Posteriorteeth-multiple
Continuouswiththeperiapical
connectivetissuesthroughthe
apicalforamen

12. Histology
4zones:
Odontoblasticzone
Cellfreezoneofweil
Cell-richzone
PulpCore

14. Structure of pulp:
Intercellular
substance
Pulp
Cells

15. Structure of pulp:
Cells
Odontoblasts
Fibroblasts
Immunocompetent
cells
Macrophages
Undifferentiated
ectomesenchymal cells

16. Odontoblasts:
Secondmostprominentcellsofpulp
palisadepatternofarrangementinthe
crownofthematuretooth
Constantlocationadjacenttothe
predentin-odontogeniczoneofthe
pulp
Cellbodyinpulp&cellprocessesinthe
dentinaltubules
Tallcolumnarincrown,cuboidalin
middleofroot&flatspindleshapednear
theapexoftooth

18. Microvasculature of dental pulp:

20. Odontoblasts:
Diameter-5-7micronm
Length-25-40micronm
Pulp-dentineinterface-59,000-76,000per
squaremillimeterincoronaldentinwithlessin
root
Activecell-elongated,basallyplacednucleus&
abasophiliccytoplasm
Restingcell-stubby,littlecytoplasm&
haematoxyphilicnucleus
Transitionalstage-intermediatebeteenactive
&restingstage

21. Odontoblasts:
Undergoapoptoticcelldeath–shownby
markerbcl-2
Releaseinterleukin-8
Nitricoxidesynthetasehavebeen
identifiedinodontoblasts

22. Fibroblasts:
Cellsoccurringingreatestnumbers
inthepulp
Moreinnumberinthecoronal
portionofpulpwheretheyformthe
cell-richzone
Form&maintainthepulpmatrix,
whichconsistsofcollagen&ground
substance

23. Fibroblasts:
Theyfunctionincollagenfiber
formation
Inyoungpulpthecellsdivide&are
activeinproteinsynthesis
Inolderpulptheyappearrounded
orspindleshapedwithshort
processes& exhibitfewer
intracellularorganelles–fibrocytes

24. Fibroblasts:
Immaturepulp-cellularelements
predominate
Maturepulp-fibrouscomponents
predominate
Dualfunction;Inadditionto
formingthepulpmatrix,capableof
ingesting&degradingthesame
matrix

25. Fibroblasts….
SecreteangiogenicfactorslikeFGF-2
&VEGF
Secretecolonystimulatingfactor
Incellcultureonstimulationform
mineralizedtissue

27. Macrophages
Ovalorspindleshaped
Macrophagesarepresentinthenormal
dentalpulp&aremoredensearoundthe
bloodvesselsoftheinnerpulp&around
theodontoblastlayer

28. Dendriticcells:
Bonemarrow-derived,antigen
presentingdendritecellsarefound
in&aroundtheodontoblastlayerin
noneruptedteeth&ineruptedteeth
beneaththeodontoblastlayer
FunctionissimilartoLangerhans
cellsinthattheycapture&present
foreignantigentotheTcells

29. Dendriticcells:
Participateinimmunosurveillance
&increaseinnumberincarious
teeth
Dendriticcells&macrophages
constitutesome8%ofthetotal
cellpopulation,withdendritic
cellsexceedingmacrophages

30. Undifferentiated
ectomesenchymal cells
Totipotentcell
Dependinguponthestimulusthese
cellsmaygiverisetoodontoblasts,
fibroblastsormacrophages.
Represent the pool from which
connective tissue cells of the pulp are
derived

31. Matrix & ground substance
Collagen-typeI&typeIII
Ground substance composed of
glycosaminoglycans,glycoproteins&water
Groundsubstancelendsupporttothecellsof
thepulp&alsoserveastransportmediumof
nutrientsfromthebloodvesselstothecells&
transportofmetabolitesfromcellstoblood
vessels

32. Pulpal stem cells
Migratetothesiteofinjured
odontoblasts&producedentin
TGFbeta1&BMP-2involvedinthe
migrationofstemcells
Pluripotent-adipocytes&neuralcells

33. Pulpal stem cells
Produce dentinogenesis &
osteogenesis
Dentinsialoproteinpresent
Dentoninstimulatedentalpulpstem
cell
Pulptisueof3
rd
molars-viableafter
cryopreservation

34. Functions of pulp
1.Inductive: interactwithoral
epithelialcellsleading to
differentiationofdentallamina&
enamelorganformation
2.Formative:formationofdentin
3.Sensory:sensationoftoothisfelt
throughthenervesofthepulp

35. Functions of pulp
4.Nutritive:suppliesnutritiontothe
dentinthroughbloodvessels&
odontoblasticprocesses&maintainthe
vitalityoftooth
5.Defensiveorreparative:protectsit
self&vitalityofthetoothbyproducing
reparativedentin

36. Blood vessels of the dental pulp:
Supplyoxygen&nutrientswheretheyare
mostneededduringdentinogenesis
Pulpalbloodflow-
1.inarterioles-0.3to1mm/sec
2.Invenules-approx.0.15mm/sec
3.Incapillaries-approx.0.08mm/sec
Arise from inferior or superior alveolar
artery

37. Blood vessels of the dental pulp
Vessels possess 3 layers:
1.Tunicaintima-squamousorcuboid
cells
2.Tunicamedia-5micromthick&consists
ofonetothreelayersofsmoothmuscle
cells
3.Tunicaadventitia-madeupoffew
collagenfibres

38. Blood vessels of the dental pulp:
Pericyteliesonthesurfaceofvessels
Arterio-venousshuntsregulatebloodflow
Blood capillaries–8-10micromin
diameter
Fenestratedcapillaries-rapidtransportof
metabolitesduringdentinogenesis

41. Nerves of the dental pulp
Nervesenterpulpthroughapical
foramen,alongwithafferentblood
vessels&togetherformthe“neuro-
vascularbundle”
Nervebundlesthatenterthepulp
consistsprincipallyofsensoryafferentsof
thetrigeminalnerve&sympathetic
branchesfromthesuperiorcervical
ganglion

42. Nerves of the dental pulp
Inthecrownthereisapronounced
plexusofnervesbeneaththe
odontoblasts,knownastheplexusof
Raschkow–occupy the cell-
freezoneofweil&canbedemonstrated
insilverstainedsectionsunderlight
microscopeorbyimmunocytochemical
techniques
Intheroot-nocorrespondingplexus

44. Nerves of the dental pulp
Eachbundlecontainsmyelinated&
unmyelinatedaxons
Myelinatedaxonsloosemyelin-asthe
nerveascendcoronally
Substance-P,5-hydroxytryptamine,
vasoactivepeptide,somatostatin&
prostaglandinsaswellasacetycholine
&norepinephrine–foundthroughout
pulp

45. Nerves of the dental pulp:
Neuropeptides--Calcitoningenerelated
peptide(CGRP)&Substance-P→
potentvasodilators
Nor-epinephrine&neuropeptideY→
vasoconstrictors
Substance-P→nonreceptivetransmitter
Somatostatin→actagainstit
Pulporganslackreceptorsforheat,
touch,pressureorchemicals

47. Regressive changes (aging)
Fibrosis
•Accumulationofbothdiffusefibrillar
components&bundlesofcollagen
fibers
•Externaltraumasuchasdentalcariesor
deeprestorationscauseslocalized
fibrosisorscarringeffect
•Atheroscleroticplaquesmayappearin
pulpalvessels
•Calcificationsarefoundthatsurround
vessels

48. Regressive changes (aging)
Pulp stones (denticles):
•Nodular,calcifiedmassesappearingin
eitherorboththecoronal&root
portionsofthepulporgan
•Asymptomatic,unlesstheyimpingeon
nervesorbloodvessels
•Seeninfunctionalaswellasembedded
uneruptedteeth

50. Regressive changes (aging)
Pulp stones
(denticles):
True
denticles
False
denticles

51. Pulp stones:
Truedenticles:
•Similarinstructuretodentin
•Arerare,locatedclosetotheapicalforamen
•Developmentiscausedbytheinclusionof
remnantsoftheepithelialrootsheathwithin
thepulp
•Theseepithelialremnantsinducethecellsof
thepulptodifferentiateintoodontoblasts,
whichthenformthedentinmassescalled
truepulpstones

52. Pulp stones:
Falsedenticles:
•Donotexhibitdentinaltubules
•Concentriclayersofcalcifiedtissue
•Somecasescalcificationsitesappear
withinabundleofcollagenfibers
•Phleboliths-serveasnidiforfalse
denticles
•Alldenticlesbeginassmallnodules
butincreaseinsizebyincremental
growthontheirsurface

53. Pulp stones:

54. Pulp stones
(depending on their
relation to the
dentin of tooth)
Free
Attached
Embedded

56. Pulp stones:
Freedenticles:
entirelysurroundedbypulptissue
Attacheddenticles:
partlyfusedwiththedentin
Embeddeddenticles:
entirelysurroundedbydentin

57. Pulp stones:
Incidence–
66%ofteeth-10-3oyears
80%ofteeth-30&50years
90%-over50yearsofageFree
denticles:

58. Diffuse calcifications
Irregularcalcifieddeposits
followingcollagenfibrebundlesor
bloodvessels
Foundmoreintherootcanal&
lessincoronalarea
Surroundbloodvessels-dystrophic
calcification

59. Diffuse calcifications

60. Clinical considerations:
Wide pulp chamber in the tooth of a
young person will make a deep cavity
preparation hazardous
Dehydration cause pulpal damage
Associatedwithtrauma,thepulp
becomestransformedintogranulation
tissueandthedentinecommencestobe
resorbedinternallyatthepulp-dentine
surface

61. Diseases of dental pulp
Etiology –
1. Dental caries
2. Tooth fracture –trauma
cracked tooth syndrome
3. Anachorectic pulpitis
-anachoresis –phenomenon by which blood borne
bacteria, dyes, pigments, metallic substances, foreign
products & other materials are attracted towards the
site of inflammation
-probable cause –increased capillary permeability in
particular area

62. 4. Chemical irritation –erosion
acidic restorative material
5. Thermal changes –polishing procedures
cavity preparation
tooth restored with
exothermic
restorative
material.
6. Galvanic currents
7. Periapical tissue –accessory canals
8. Aerodontalgia

63. Classification of
pulpitis
•Acute
•Chronic
•Both acute and chronic –
Partial or focal pulpitis
Total or generalised
•Closed pulpitis
•Open pulpitis

64. References
Orban’s oral histology &embryology-12
th
edition
Ten Cate’s oral histology-7
th
edition
Oral anatomy, histology and embryology;
Berkovitz, 3
rd
edition
Essentials of oral histology &
embryology, 2rd edition, James k . avery

65. Thank you
Thank you