The document provides an overview of the anatomy and histology of the dental pulp. It defines the pulp as the soft tissue contained within the pulp chamber and root canals of teeth. The pulp contains odontoblasts, fibroblasts, nerves, blood vessels, and an extracellular matrix. Age-related changes can cause decreases in the pulp size and vascularity as well as increases in fibrosis and calcification. Various dental materials and procedures can affect the pulp, with potential outcomes including inflammation, necrosis, and resorption. Recent advances include efforts to regenerate pulp tissue using stem cells and biomolecules.

1. DEPARTMENTOFPAEDODONTICSANDPREVENTIVEDENTISTRY
C.K.STEJAINSTITUTEOFDENTALSCIENCES,TIRUPATI
PREPARED BY : L. MAHESHWAR REDDY
1ST YEAR M.D.S

2. CONTENTS
• Introduction
• Embryology
• Anatomy
• Structural organization
of pulp
• Cells of pulp
• Extra-cellular matrix
• Circulation of pulp
• Metabolism of pulp
•Innervation of pulp
• Functions of pulp
• Pulp of deciduous
teeth
• Age changes
• Clinical
considerations
• Recent advances
• Conclusion
• References

3. INTRODUCTION
DEFINITION:
According to Cohen - the pulp is a soft
tissue of mesenchymal origin residing
within the pulp chamber and root canal of
teeth.
SALIENT FEATURES

4. Maxillary
(Cubic Centimeter)
Mandibular
(Cubic Centimeter)
Central Incisor 0.012 0.006
Lateral Incisor 0.011 0.007
Canine 0.015 0.014
First Premolar 0.018 0.015
Second Premolar 0.017 0.015
First Molar 0.068 0.053
Second Molar 0.044 0.032
Third Molar 0.023 0.031

5. DEVELOPMENT

6. ANATOMY OF PULP
CORONAL PULP
It is the pulp occupying the pulp chamber of the
crown of the tooth
RADICULAR PULP
•It is the pulp occupying the pulp canals of the root
of the tooth

7. APICAL FORAMEN ACCESSORY CANAL

8. Structural Organization of pulp

9. Dentin
Predentin
Odontoblasts
layer
Cell free
zone
Cell rich
zone Pulp
core

10. Histology of pulp
Morphologic zones of pulp-
 ODONTOBLAST LAYER
 CELL-POOR ZONE
 CELL-RICH ZONE
 PULP PROPER

11. Odontoblastic layer
CELL FREE ZONE CELL RICH ZONE

12. PULP CORE
The pulp proper is the central mass of the pulp
It contains the larger blood vessels and
nerves.
 The connective tissue cells in this zone are
fibroblasts, or pulpal cells.

13. Histological Structures of the Pulp
The dental pulp is formed of specialize loose
connective tissue contain :
1) Cellular elements :
a. Formative cells : Odontoblast, Fibroblast .
b. Progenitor cells : Undifferentiated mesenchymal
cells
c. Defensive cells : Macrophages, neutrophils,
eosinophils, basophils, mast cells , plasma cells and
Lymphocytes.

14. 2) Fibrillar elements :
a. collagen bundles
b. fine collagen fiber
3) Ground substance: Act as a medium to transport
nutrients to cells and metabolites of the cell to the
blood vessels.
4) Neurovascular elements : Blood vessels, nerves,
lymph vessels

15. ODONTOBLAST
• Second most common cells in the pulp.
Dentin Pulp
Odontoblast process Odontoblast cells

16. ODONTOBLASTIC PROCESS JUNCTIONAL COMPLEXES

17. b- Fibroblasts

18. UNDIFFERENTIATED MESENCHYME

19. IMMUNOCOMPETENT CELLS
 They play a major role in local inflammation and
immunity.
 They are recruited from blood stream & remain
as transient inhabitants in pulp
 These cells are
-Lymhpocytes
-Macrophages
-Dendritic cells
-Mast cells

20. A- Histiocyte ( macrophage ) :
B-Plasma cells:

21. LYMPHOCYTES IN PULP
DENDRITIC CELLS Eosinophils

22. MAST CELLS

23. • COLLAGEN
• ELASTIN
• FIBRONECTIN
• LAMILIN
GAG PR OTEOGLYCAN

24. Collagen fibers

25. Von kroff fibres
 Collagen has been described as having a
unique arrangement in the peripheral pulp,
these bundles of collagen are called Von
kroff bundles.

26. GROUND SUBSTANCE
• It is a structureless mass, gel-like consistency,
makes up the bulk of the pulp
• Consists complexes of proteins, carbohydrate and
water.
• Broadly classified as
a.Proteoglycans-
Functions of GAG-
1.Water retention
2. Ion binding & electrolyte distribution during
mineralization (Bowness 1968).
b. Glycoproteins

27. • Maintain tissue’s physical
properties and integrity
• Control of growth and development
and repairs
• Control of cell migration
• Control of diffusion of
macromolecules
FUNCTIONS OF PULPAL
EXTRACELLULAR MATRIX

28. CIRCULATION OF THE PULP
 Systemic circulation:-
Pulp organ is extensively vascularised with blood vessels arising from
internal maxillary artery
Internal maxillary artery
Mandibuar artery pterygoid artery Pteygo-palatine artery
Inferior alveolar artery infraorbital artery posterior
superior
alveolar artery
Dental incisive mental anterior superior alveolar
branch artery artery
molars, incisors lower lip incisors, bicuspids molars,
bicuspids
premolars

29. Microcirculation:
Arterioles
(50μ diameter)
▼
Terminal arterioles
▼
Precapillaries
▼
Metarterioles
▼
Capillaries (8μ)

30. SEM shows extensive arborization of
capillaries from the metarterioles

31. CAPILLARIES:
Venules LYMPHATICS

32. REGULATION OF PULPAL BLOOD FLOW
 Neuronal regulation
a. Sympathetic fibers
b. Parasympathetic fibers
c. Peptidergic afferent fibers
 Endocrine & paracrine regulation

33. INNERVATION
 Principle role is to help in conscious recognition of
irritants to the pulp, which gives the opportunity to have
the problem corrected before irreversible effects can
occur
 Nerve fibers, mylinated & unmyelinated , enter the tooth
through the apical foramen
Dental pulp
Sensory afferent
fibers
Motor
nerves
Branches of maxillary &
mandibular divisions of trigeminal
nerve.
Sympathetic division of
autonomic
nervous system

34. Plexus of Rashkow

35. Sympathetic Innervation
Sympathetic nerve fibers forming plexus
around arterioles

36. Neuropeptides
 They are proteins that have been associated
with central & peripheral nervous system.
 Following are the neuropeptides demonstrated
in nerves of dental pulp:
Substance p
 5 hydroxy tryptamine
 Vasoactive intestinal peptide
 Prostraglandin
 Somatostation
 Acetylcholine
 Norepiepheine

37. Nerve Plexus of Raschkow
 Sensory nerve fibers that originate
from inferior and superior alveolar
nerves innervate the odontoblastic
layer of the pulp cavity. These
nerves enter the tooth through the
apical foramen as myelinated nerve
bundles. They branch to form the
subodontoblastic nerve plexus of
Raschkow which is separated from
the odontoblasts by a cell-free zone
of Weil. In addition to the sensory
nerves, sympathetic nerve bundles
also enter the tooth to innervate

38. A, Odontoblasts; B, Cell-free zone of Weil; C, Nerve plexus of Raschkow

39. A-delta fibers
 Conduction velocity 2-30 m/s
 Lower threshold
 Involved in fast, sharp pain
 Stimulated by hydrodynamic
stimuli
 Sensitive to ischemia
 Sharp pain
C fibers
 Conduction velocity 0-2 m/s
 Higher threshold
 Involved in slow, dull pain
 Stimulated by direct pulp
damage
 Sensitive to anesthetics
 Dull pain
A-beta fibers
 Conduction velocity 30-70 m/s
 Very low threshold, non-noxious
sensation
 40% of myelinated fibers in pulp
 Functions not fully known
Non-myelinated
sympathetic fibers
 Conduction velocity 0-2 m/s
 Post-ganglionic fibers of superior
cervical ganglion
 Vasoconstriction & Vasodilation.

40. Nerves in
pulp

41. Dentin pulp complex
 Dentin the most voluminous at mineralized
connective tissue of the tooth forms the hard
tissue portion of the dentin pulp complex where
as dental pulp is a living soft connective tissue
maintains the vitality of the dentin (Linde and
Goldberg 1993, Torneck 1994)
 Dentin contains multiple closely packed dentinal
tubules in which the dentnal fluid and the
cytoplasmic process of the cells that have
formed the dentin, the odontblast are
located(Torneck 1994)
 The unity of dentin and pulp is responsible for

42. FUNCTIONS OF DENTAL PULP
 INDUCTIVE
 FORMATIVE
 NUTRITIVE
 PROTECTIVE
 DEFENSE

43. PULP OF DECIDUOUS TEETH
Anatomical
differences-
o Dimensions
o Pulp chamber
o Pulp horns
o Cervical constrictions
o Root canals
o Accesory canals
o Apical foramen
Histological
differences-
o Degree of cellularity
o Vascularity
o Innervation

44. AGE CHANGES
 Various age changes in pulp are-
- Dimensional changes
- Cellular changes
- Pulpal fibrosis
- Calcifications
- Changes in vascularity

45. Age changes in the pulp
The size of the pulp
The apical foramen
The cellular elements
The bl. vessels & n.
Vitality
Reticular atrophy: The total affect is the
production of a lessened vitality of the pulp
tissue and a lessened response to stimulation.
decreased

46. Pulpal fibrosis

47. PULP CALCIFICATIONS
 It is a common occurrence with incidence of 50% of all
teeth
 Size may range from microscopic particle to stones that
may occlude the pulp chamber
 Composed of carbonated hydroxyapitite crystals
 Pulp calcification may be-
-Pulp stones
True pulp stones
false pulp stones
-Diffuse calcifications
-Calcific Metamorphosis

48. Sundell Schematic
Presentation
Local
Metabolic
Dysfunction
Trauma
Hyalinization of
injured cell
Vascular
Damage
Thrombosis
Vessel Wall
Damage
FibrosisMineralization
Growth
Pulp Stones

49. Denticles
True denticle-
False denticle-

51. attached
free
Attached denticle
Free denticle

52. Diffuse Calcification

53. Calcific Metamorphosis
 Luxation of teeth as a result of trauma may result in
calcific metamorphosis
 Usually results in partial or complete radiographic
obliteration of the pup chamber
 Resembles cementum or bone on dentinal walls
 Teeth may present with a yellowish hue

54. Decrease in quality of blood vessels
Blood vessels:-
 Aging has an adverse effect on the number & quality of
blood vessels supplying the dental pulp (Benefit 1965)
 The arterioles in the older pulp exhibited hyperplasia of
the intima & dystrophic changes in the media &
adventitia.

55. CLINICAL CONSIDERATIONS
 Anatomical considerations
 Effect of dental materials on pulp
 Effect of Operative Procedures

56. EFFECT OF DENTAL MATERIALS ON PULP
 Amalgam
corrosion products inhibit cell growth
high thermal conductivity
 Glass ionomers
well tolerated by pulp
RMGI used for direct pulp capping
 Zinc Oxide Eugenol
has an anti-bacterial and anodyne effect
The sedative effects are due to eugenol ability to
block / reduce the nerve impulse activity
higher concentrations leads to chronic inflammation,
thrombosis of vessels

57.  Formocresol
High degree of diffusion causes a chronic
inflammation of the pulp .Mutagenic and carcinogenic
 Calcium hydroxide
induces dentin bridge formation when used for direct
pulp capping
 Mineral trioxide aggregate
Superior to calcium hydroxide as a direct pulp capping
agent

58.  Zinc Phosphate
Strong to moderate cyto-toxic reactions is due to
leeching of zinc ions and low Ph
 Resin adhesive systems
The formation of hybrid layer secures the enamel-
resin interface with a continuous seal which acts as a
biometic barrier
Dentin bonding agents
Monomer molecules reaching the pulp can irritate the
pulp causing inflammation

59.  Acid etching –
Etching apparently increases the pulpal inflammation
because it removes the debris that accumulate over the
dentinal tubules when they are cut thereby facilitating the
penetration of irritants into dentinal tubules
EFFECT OF OPERATIVE PROCEDURES
 Effects of tooth preparation
Pressure and Frictional heat
Desiccation
Exposure of dentinal tubules
Direct damage to odontoblast process

60. CAVITY DEPTH
 1mm – Shields Pulp
 0.5- 0.25mm – Tertiary Reactive Dentin
 0.25mm> ~ Odontoblasts die & Reperative
dentin is formed very fast.

61. CAVITY DRYING
Strong capillary forces
Outward flow of Dentinal
fluid/Odontoblast displacement
This is replaced by fluid from
the pulp
Stimulates Nociceptors
Produces Pain

62. PULPAL
PATHOLOGIES
•Reversible pulpitis
•Irreversible pulpitis
•Chorinic hyperplastic pulpitis
•Internal resorption
•External resorption

63. Irreversible pulpitis
Chorinic hyperplastic pulpitis

64. External Resorption
Internal resorption-

65. Recent advances
Pulpal regeneration-
 This exciting new era was found by Urist with the
introduction of bone morphogenic protein
 In pulpal regeneration the tissue would be isolated from
noxious restorative material in the chamber, thereby
diminishing the chances of resorption.
 BMP’s are osteogenic proteins implicated in cell
differentiation, tissue morphogenesis, regeneration and
repair.

66. Stem cells
• Dental pulp stem cells are multipotent stem cells that have
a potential to differntiate into a variety of cell types.
• Historically, dental stem cells were first isolated by
“Gronthos” and co-workers from the dental pulp.
• Animal studies have shown the great potential of DPSCs
for repair and regeneration of various tissues, such as,
heart, muscles, and teeth
• Clinically a bio- teeth made from autogenous DPSC,s
should be the best choice for clinical tooth reconstruction

67. •There are two widely used methods for the isolation
of dental pulp stem cells: the explant method (DPSC-
OG) and the enzymatic digestion method of the pulp
tissue (DPSC-EZ) .

68. •It has been demonstrated that the outgrowth method allows
DPSCs to differentiate into skeletal muscle fibres.
Markers expressed by DPSCs are CD29 and CD44,CD34 as
well as CD73 and CD105 and CD 117. This population has
great self-expansion and osteogenic differentiation
capabilities and produces a living autologous fibrous bone
(LAB) tissue in vitro and bone tissue when implanted in mice.

70. Conclusion
 we, as dental physicians, provide the highest level of
technical and scientific accuracy and artistic flair in the
holistic well being of the tooth organ and in turn fulfill
the aspiration of those individuals who place in us their
unwavering trust - our patients.

71. Refences
• Dental pulp; Seltzer and bender; 3rd editiony;
• Oral Histology; Tencate; 5th Edn
• Oral Histology & Embryology; Orban 11th Edn
• Pathways of Pulp; Cohen; 8th Edn
• Endodontics; Ingle; 5th Edn
• Textbook Of pedodontics; Shobha Tandon

72. • ANCA VIŢALARIU1), IRINA-DRAGA CĂRUNTU2) Department
of Oral Rehabilitation, Faculty of Dentistry, “Gr. T. Popa” University
of Medicine and Pharmacy, Iassy 2) Department of Oral Biology,
Faculty of Dentistry, “Gr. T. Popa” University of Medicine and
Pharmacy, Iassy-2005
• Review ofDental pulp stem cells: State of the art and suggestions for
a true translation of research into therapy Marcella La Noce a ,
Francesca Paino a , Anna Spina a , Pasqualina Naddeo a , Roberta
Montella a , Vincenzo Desiderio a , Alfredo De Rosa b , Gianpaolo
Papaccio a, *, Virginia Tirino a, *, Luigi Laino c-2014