2. Dynamics of Dental Pulp & Periapical Pathologies
Deepti Awasthi
P G student

3. CONTENTS Introduction Development Anatomy Structural features
Blood vessels
Lymph vessels
Nerves
Functions
Differences in primary & permanent pulp organ

4. Age changes
Classification of pulpal pathologies
Reversible pulpitis
Irreversible pulpitis
Acute apical periodontitis
Phoenix abscess
Periapical granuloma
Radicular cyst
External resorption
Internal resorption
Pulp necrosis
Conclusion
References

5. Definition
Dental pulp, a small mass of connective tissue, blood vessels, and nerves located in a chamber within the dentin layer of a tooth. The pulp chamber is found in the crown and the root of a tooth.
Mosby's Medical Dictionary, 8th edition. © 2009, Elsevier

6. ://
Introduction

7. Regeneration of tooth pulp dentin
Development
Regeneration of tooth pulp dentin

8. ANATOMY
General features
volume

9. Coronal pulp
6 surfaces
pulp horns

10. Radicular pulp
single , multiple
tubular shape
growth –more dentin – pulp gets narrower

11. location & shape may undergo changes
Apical foramen
avg. size in adults
location & shape may undergo changes
frequently , there are 2 or more foramina seperated by a portion of dentin & cementum or by cementum only.
orbans

12. Textbook of Endodontics – Nisha Garg
Accessory canals
from radicular pulp laterally through the root dentin to the pdl tissue
apical third
clinically significant in spread of infection
Mechanism of accessory canal formation :
Textbook of Endodontics – Nisha Garg

13. STRUCTURAL FEATURES
Histologically,
Human anatomy II, DDS 09

14. Principal cells :
odontoblasts
fibroblasts
undifferentiated mesenchymal
macrophages
lymphocytes
dendritic cells
Intercellular substances :

15. Intercellular substances
Dense & gel like
Acid muco polysaccharide & protein polysaccharide
During early development, chondroitin A,B & hyaluronic acid.
Lends support to the cells of the pulp
Transport of nutrients & metabolites
Gag –hydrophilic,forms a gel – high tissue fluid pressure.
orbans

16. Fibroblasts Most numerous Function –
Stellate shape & extensive processes
Electron micrograph – RER , mitochondria etc
Young pulp – divide & are active in protein synthesis
Older pulp – spindle shaped , fibrocytes
Mature & immature pulp-
orbans

18. Inflammation & healing Fibres – type I & III length – 10 – 100nm
Dual function
Inflammation & healing
Fibres – type I & III
length – 10 – 100nm
cross striation at 64 nm
After root completion, pulp matures & bundles of collagen fibres increase in number.
Apical region
orbans

19. Textbook of endodontics
Fibres are more numerous in radicular pulp than coronal & greatest concentration of collagen occurs in the most apical portion of the pulp. This is of practical significance as engaging the pulp with a barbed broach in the apex region affords a better oppurtunity to remove the tissue intact.
Textbook of endodontics

20. Undifferentiated mesenchymal cells
Totiopotent cell
Light microscope – large polyhedral cell ,large lightly stained centrally placed nucleus.
Decrease in old age – reduces the regenerative potential of the pulp
orbans

21. Odontoblasts 2nd most prominent
Adjacent to the predentin with cell bodies in the pulp & processes in the dentinal tubules.
Diameter um
Length – um
Cell bodies – large oval nuclei , fills the basal part of the cell
Adjacent to the nucleus basally, RER & golgi app
Pulpal predentin junction – no organelles
orbans

22. Odontoblasts mainly synthesize type I collagen ,proteoglycans & also secretes dentin sialoprotein, alkaline phosphatase , phosphophoryn involved in extracellular mineralization.
Pathways of pulp

25. More cylindrical & longer – crown More cuboid – middle of root
Cell junctions :
macula adherens
tight junctions
gap junctions
More cylindrical & longer – crown
More cuboid – middle of root
Ovoid & spindle shaped – close to apex
Releases IL-8 , chemotactic for neutrophils
Nitric oxide synthetase – vasodilation & blood pressure regulation
Berkowitz

26. DEFENCE CELLS Histiocyte / macrophage –
Inactive –difficult to distinguish from fibroblasts
Pulpal inflammation- exhibit granules & vacuoles in their cytoplasm , nuclei increases
Small blood vessels & capillaries
Aggregate of vesicles or phagosomes
orbans

27. Similar to langerhan’s In deciduous teeth – odontoblasts
Dendritic cells
Similar to langerhan’s
In deciduous teeth – odontoblasts
Increase in areas affected by caries, attrition or restorative procedures
Immunocompetent cells in deciduous teeth increased in number during shedding.
Tencates

28. Mast cells – vessels in the inflamed pulp. Plasma cells – antibodies
Lymphocytes
Mast cells – vessels in the inflamed pulp.
Plasma cells – antibodies
light microscope – nucleus appears small & concentric
cart wheel appearance
Orbans

29. lymphocyte
Mast cell

30. BLOOD VESSELS
The blood vessels – arise from inferior or superior alveolar artery & drain by same veins
Small arteries & arterioles – apical canal & pursue a direct route to the coronal pulp. Along their course they give off numerous branches in the radicular pulp that passes peripherally to form plexus in the odontogenic region .
Pulpal pressure – among the highest
Tencates

31. Regeneration of tooth pulp & dentin

32. LYMPH VESSELS
Endothelium lined tubes that join thin walled lymph venules or veins in the central pulp.
Capillaries – thin walls
Central part of the pulp.
Lymph vessel draining the pulp & pdl – common outlet.
Anterior teeth – submental
Posterior teeth – submandibular & deep cervical nodes

33. NERVES non-myelinated 150-1200
Larger fibre range 5 & 13 um, majority are smaller than 4 um
Perineurium & epineurium – thin
Parietel layer, plexus of rashkow
pulp horns
berkovitz

34. The sensory nerves of the pulp arise from the trigeminal nerve.
The mature deciduous teeth-well innervated, esp coronal pulp , has many nerve endings terminating in or near odontoblast layer , with a few penetrating into dentin.
No clear evidence that any sensation other than pain can be experienced fron pulp.
The sensory nerves of the pulp arise from the trigeminal nerve.
Pathways of pulp

35. Textbook of endodontics
A$ -
myelinated
faster
pulp- dentin junction
sharp,pricking, localized
C – sympathetic efferents
non myelinated
throughout the pulp
dull & more diffuse pain
Textbook of endodontics

36. EPT stimulates A delta fibres first because of their lower threshold
EPT stimulates A delta fibres first because of their lower threshold. As intensity of stimulus is increased, some of the C fibres also get stimulated.
The relatively late appearance of A fibres in the pulp may explain why EPT tends to be unreliable in young teeth since A fibres are more easily stimulated than C fibres.
Pathways of pulp

37. FUNCTIONS Tencates INDUCTIVE FORMATIVE NUTRITIVE PROTECTIVE REPARATIVE
DEFENSIVE/
Tencates

38. Differences in primary & permanent pulp tissues
PRIMARY PULP
Function for only about 8yrs & 3 mths duration
3 time periods :
Period of growth of pulp organ :
in about 1yr time , the crown & roots of the teeth develop
orbans

39. 2. Period of maturation of pulp:
root is completed & resorption of root begins at about 3yrs to 9 mths of age
3. Regression of pulp :
period of regression of deciduous radicular pulp depends on the time from the completion of the permanent crown till the time of permanent tooth eruption.
Max. life of primary pulp organ : 9yrs & 6mths.
orbans

40. Primary teeth – 4yrs, 2mths
PERMANENT PULP ORGAN
The pulp undergoes development for about 12 yrs ,4mths.( crown calcification to root completion )
Primary teeth – 4yrs, 2mths
Period of pulp aging is much accelerated in primary teeth.
Maxillary arches require slightly longer to complete each process of development.
orbans

41. AGE CHANGES
Most conspicuous change – decreasing volume of the pulp chamber & root canal
In old teeth , RC is often a thin channel.
sometimes almost completely obliterated.
Continued restriction in pulp volume –decrease in vascular supply & initiates other age changes.
orbans

42. Reduction in size & no. of cytoplasmic organelles.
Cell changes
Reduction in size & no. of cytoplasmic organelles.
20 yrs of age , cells gradually reduce in no.
until age 70 ,cell density has decreased by about half.
orbans

43. Fibrosis Radicular pulp – arranged longitudnally in bundles
Coronal pulp – random/diffuse
Any external trauma – localized fibrosis or scarring effect.
Collagen increase is noted in media & adventitia layer of blood vessel

44. Vascular changes Reduced vascularity Blood flow is decreased.
Calcification in the walls of blood vessels – near apical foramen
Atherosclerotic plaques may appear
Tencates

45. Pulp stones
Denticles
Calcified masses appearing in either or both the coronal & root portions of the pulp organ
Usually are asymptomatic, unless impinge on nerve or blood vessel.

47. Textbook of endodontics
CLASSIFICATION
Acc to structure :
true
false
Acc to relation with Dentin :
free
attached
embedded
Textbook of endodontics

49. True Similar to dentin Close to the apical foramen
Development – inclusion of remnants of HERS
within the pulp.
they induce the cells of the
pulp to differentiate into
odontoblasts which form the
dentin masses.
Tencates

50. False Appear as concentric layers of calcified tissues
They appear within a bundle of collagen fibres.
Some arise around vessels.
In the centre – remnants of necrotic & calcified cells.
Phlebolith – may serve as nidi for false denticles.
Tencates

51. Free – Attached- Embedded- 90% - > 50yrs of age
Tencates

52. Diffuse calcification
Irregular calcific deposits in the pulp tissue usually following collagenous fibre bundles or blood vessels.
usually found in the root canal , whereas denticles are more in coronal pulp.
orbans

53. Textbook of endodontics
CLASSIFICATION
Acc to Grossman:
Pulpitis
Reversible
symptomatic
asymptomatic
Irreversible
acute
responsive to cold
responsive to heat
Textbook of endodontics

54. chronic
Asymptomatic
hyperplastic pulpitis
internal resorption
Pulp degeneration
calcific
Others
necrosis

55. WHO Classification K04.4 – AAP K04.5 – CAP K04.6 – PA with sinus
K04.60 – PA with sinus to max antrum
K PA with sinus to nasal cavity
K PA with sinus to oral cavity
K PA with sinus to skin
K PA without sinus
K PC
K apical & lateral cyst
K Residual cyst
K inflammatory paradental cyst
Pathways of pulp

56. Ingle’s Classification
Painful Pulpoperiapical Pathologies
1. AAP
2. Advanced AP
a. Acute Apical Abscess
b. phoenix abscess
c. suppurative apical periodontitis

57. Non – Painful
1. Condensing osteitis
2. CAP - incipient stage
3. CAP
- Periapical granuloma
- periapical cyst
- suppurative apical periodontitis

59. Acute Apical Periodontitis

60. Acute Apical Abscess

61. Phoenix Abscess
An acute inflammatory reaction superimposed on an existing chronic lesion, such as cyst or granuloma.

62. Periapical Granuloma

63. Radicular Cyst

64. External Root Resorption

65. Internal Resorption

66. Pulp Necrosis

67. Textbook of endodontics
Effect of posture on pulpal flow
In normal upright posture , there is less pressure effect in the structure of head. Lying down increases blood flow to pulp by removal of both gravitational & baroreceptor effect.
Textbook of endodontics

68. Regeneration of tooth pulp & dentin
Regeneration of pulp dentin
Regeneration of tooth pulp & dentin

69. conclusion

70. References Orban’s Oral Histology &Embryology- 12th ed
Pathways of the pulp –stephen Cohen 9th ed
Textbook of endodontics – Nisha garg & Amit garg
Oral histology –Tencates
Berkovitz
Regeneration of tooth pulp and dentin : trends and advances. Sarang Sharma, Vimal Sikri.Annals of Neurosciences, Volume 17, Number 1, January 2010