indirect and direct pulp capping procedures and recent advances

1. Pulp
Protection
Restoring the Tooth’s own
heartbeat
Dr.Abhijit Pallewar
2nd Year PG
Dept Of Conservative Dentistry And Endodontics

2. CONTENTS
• Introduction
• Pulp –dentin complex
• Pulp nerve supply
• Pulp response
• Pulp irritants
• Protection in shallow and moderate cavities

3. • Pulp protection in deep cavities
• indirect pulp capping
• Direct pulp capping
• Materials used for pulp protection
• New materials and methods to protect pulp
• References
• conclusion

4. INTRODUCTION
• The restoration and maintenance of dental health through
adequate restorative treatment in order to protect pulp function
is the main purpose of restorative dentistry.
• The dental pulp is a soft connective tissue of mesenchymal
origin present within the pulp chamber and root canals of
teeth.
• It is not considered an external tissue, yet its exposure to
external stimuli is unceasing due to several factors that make
the pulp extremely sensitive to environment outside.

5. • Protection of dentin-pulp complex is an important factor in
pulp vitality during operative procedures.
• This involves the avoidance of thermal stimuli caused by
operative procedures, toxicity of restorative materials and
bacteria penetration.

6. PULP-DENTIN COMPLEX
• The dentin and pulp must be considered as one organ because
of their intimate relationship between cellular tissue within
dentin and peripheral pulp tissue.
• As long as dentin is covered peripherally by enamel on coronal
surfaces and cementum on radicular surfaces , dental pulp will
remain healthy for life unless apical blood supply is disrupted
by excessive orthodontic forces or severe impact of trauma.

7. • Most pathological pulp conditions begin with removal of these
barriers via caries, fractures or abrasion.
• Structure and response of dentin to injury are largely functions
of the odontoblasts and other cells in pulp but these cells are
dependent on dentin for their protection and their state of
differentiation.
• Normal form and function of one cannot be maintained
without other.

8. • Hence its obvious response of pulp to any restorative material
will be influenced by its surrounding dentin .
• Therefore it is apparent that substances easily permeate dentin
permit thermal, osmotic, and chemical insults to act on the
pulpal constituents.
• This involves stimulation of odontoblast in intial stages which
may proceed to inflammation finally which often lead to
tissue destruction

9. • A classical work done by pashley et al ,using radioactive I in dog teeth ,
which clearly demonstrated that once dentin tubules are opened, molecules
can permeate to pulp easily .

10. Dentin Sensitivity

11. PULP NERVE SUPPLY
• Dental pulp has an abundant supply of both sensory and autonomic nerves.
• Majority of the nerves are sensory.
• The trigeminal ganglion supplies sensory innervations to the pulp via
maxillary and mandibular nerves.
• Nerve fibres enter the teeth via apical foramen and arborize coronally to
form plexus of rakshow in subodondoblastic region of pulp.
• Coronal dentin is more densely innervated than radicular dentin .

13. Classification Of Nerves
TYPE OF FIBER FUNCTION
Aα Motor, proprioception
Aβ Pressure , touch
Aγ motor
Aδ Pain , temperature , touch
B Preganglionic , autonomic
C Pain , postganglionic sympathetic

14. PULP RESPONSE TO IRRITANTS
• What happens when permeating substances
reach the pulp chamber ?

15. Vicious cycle of pulpal inflammation that begins with irritation of pulp , leads to a localised
response and may progress to a lesion increasing severity and eventually irreversible pulpitis

16. We have to protect it from any type of irritant

17. PULP IRRITANTS
• Bacterial irritants
• Trauma
• Iatrogenic:
i. during tooth preparation
ii. Orthodontic movement of tooth
iii. Periodontal and periapical curettage
iv. use of chemicals
v. idiopathic

18. Pulpal irritants
A) Bacterial irritants
(Most common cause for
pulpal irritation)
B) Traumatic
1-Caries
Tooth fracture
Luxation
Avulsion
Parafunctional
habits like bruxism
2- Periodontal
pocket and abscess
1-Acute trauma 2- Chronic
Trauma

19. C) Iatrogenic:
1. During cavity preparation
a) Heat production during cutting procedures:
Pulp temperature 11°C Destructive reaction
Pulpal temperature is critical and must not exceed normal
values in dental restorative procedures.
Clinical research has shown irreversible damage to pulp tissues
at levels of 60% at 5.5°C and 100% at 11°C..

20. Excessive heat generation leads to change in
dentin color due to vascular stasis and
hemorrage in the subodontoblastic vascular
plexus present in the pulp

21. b) Pressure exerted:
Pressure of hand or rotary instruments Nuclear aspiration of odontoblasts
or nerve endings from pulp tissues into the dentinal tubules  Disturb
odontoblasts metabolism leading to their complete degeneration and
disintegration.
c) Remaining Dentin Thickness (RDT)

22. 2. Orthodontic movement
3. Periodontal and periapical curettage

23. 4. Use of chemicals
Temporary & permanent fillings, bases, liners, and use of alcohol
that leads to pulpal injury due to its cytotoxicity, acidity, heat
formed and marginal leakage
Chemical irritants applied to dentin can result in
damage and disorganization in the subadjacent pulp

24. D- Idiopathic
Resorption
Aging
Internal External

25. Because of these various irritants
pulp needs protection…

27. • Direct pulp capping
• Indirect pulp capping
Conventional methods

28. Direct pulp capping is placing a
biocompatible material over the
exposed pulp to maintain
vitality and promote healing.
Direct Pulp Capping
WHY?
1) To maintain the vitality of the remaining pulp tissue
2) To prevent root canal treatment
3) To help conserve tooth structure

29. Indications
Recent small mechanical exposure of
pulp during (< 24 hours):
a) Tooth preparation
b) Traumatic injury.
No or minimal bleeding at the
exposure site.

30. Contraindications
Wide pulp exposure
Pre-operative
history of
Spontaneous
pain
Presence of bleeding at
exposure site
Radiograph doesn’t
show any pulp pathology

31. Clinical Procedure
3.When vital & healthy
pulp is exposed, check
fresh bleeding
2. Isolate the tooth
with rubber dam
1. Administer local
anesthesia
4. Clean the area with
saline solution
5. Dry it with a
cotton pellet
6. Apply calcium hydroxide
(preferably Dycal) over the
exposed area

32. 7. Give interim
restoration such as
zinc oxide eugenol
for 6 to 8 weeks
b) If not pulpotomy or
pulpectomy is requested
a) Remove the cement
to inspect the exposure
site. If secondary dentin
formation takes place
over the exposed site
restore the tooth
permanently with
protective cement base
and restorative material.

33. In indirect pulp capping, all caries are removed except the ones
that lie adjacent to the pulp. Caries near the pulp is left in place to
prevent pulp exposure and preparation is enclosed with a
biocompatible material.
Indirect Pulp Capping

34. Indications
1. Deep carious lesion near the pulp tissue but not involving it
2. No mobility of tooth
3. No history of spontaneous toothache
4. No tenderness to percussion
5. No radiographic evidence of pulp pathology
6. No root resorption or radicular disease should be present
radiographically.
Root resorption

35. Clinical Procedure
It’s the same procedure as the direct pulp capping except that the
pulp is not exposed. A thin layer of dentin and some amount of
caries is left to avoid exposure.
Placement of calcuim hydroxide and zinc
oxide eugenol dressing after excavation
of soft caries

36. Factors affecting Pulp Capping success
1) Age of the patient: Due to vascularity of the pulp, young patients have
greater potential for success than older ones
Young patient Old patient
2) Type of exposure: Mechanically done pulpal exposure has better prognosis than
exposure caused by caries, due to less pulpal inflammation and deleterious effect of
bacterial toxins on the pulp

37. 3) Size of the exposure: In large exposures, it is difficult to control the
hemorrhage and tissue seepage. Small pinpoint exposures are easy to
manage and have a greater potential for success
4) History of pain: If previously pain has not occurred in the tooth, the
potential for success is more

38. Conventional Materials
Materials used for Pulp Protection
Recent Materials
Varnish Base Sealer Liner
1) Zinc oxide eugenol liners
2) Calcium hydroxide
3) Flowable composites
4) Glass ionomers
1) Zinc Oxide Eugenol
2) Zinc phosphate cement
3) Polycarboxylate cement
4) Glass ionomer cement

39. Ether or
chloroform
Organic
copalResin
gum
Solvent
evaporates
Definition:
It is an organic copal or resin gum
suspended in solutions of ether or
chloroform.
When we put it on the tooth surface the
organic solvent evaporates leaving a
protective film
Two coats of varnish should be applied
using a small cotton pellet to ensure
sufficient wetting of cavity walls
VARNISH

40. Indications
To seal the dentinal tubules
Dentinal
tubules
Open Dentinal
tubules
Sealing dentinal
tubules with varnish
Dentinal tubules
blocked by varnish
2. Protects the tooth from
chemical irritants from cements
 reducing postoperative pain
3. Reduces microleakage
around restorations
1. Prevents discoloration of tooth
with an amalgam restoration by
preventing migration of ions into
the dentin

41. Under Composite
Resin
Varnishes dissolve in the
monomer of the resin &
also interfere with their
polymerization of resins
With Glass Ionomer
Restorations
It interferes the bonding
of tooth to these cements
Contraindications

42. Sealer
Indications
• To seal dentinal tubules
• To treat dentin hypersensitivity.
An adhesive sealer is commonly used under indirect restorations.
For application, cotton tip applicator is used to apply sealer on all
areas of exposed dentin.

43. • Liners can be classified as :
 Thin film liners( 1-50µm)
a. solution liners ( varnish:2-5 µm)
b. suspension liners ( zinc oxide / calcium hydroxide 20-25
µm)
 Thick film liners ( 200 -1000 µm)
a. GIC ( type III)
LINERS

44. Commercially available calcium hydroxide liners are DYCAL ( dentsply )
and single paste systems like CALCIMOL LC ( Voco) and Septocal LC ( Septodont)

45. 1. Zinc oxide eugenol liners
• Used to alleviate pain from mild-to-
moderate inflammation of pulp.
 In low concentration  it acts as
obtundant
 In high concentration  it acts as
chemical irritant
Contraindication:
It inhibits polymerization  Should not be used under bonding
agents & composite restorations

46. 2- Calcium hydroxide
Most common agent considered as the
“gold standard” of direct pulp capping
materials against which new materials
should be tested
Advantages:
1. Causes dentin mineralization by activating the enzyme ATPase
2. Stimulates reparative dentin formation
3. Biocompatible
4. High pH (12.5)  neutralizes acidity of silicate and zinc phosphate
cements
Disadvantages:
1. Low strength
2. High solubility Dissolves rapidlyUsed over small areas requiring pulp
protection / Applying glass ionomer or zinc phosphate base to prevent its
dissolution.

47. When it dissociates:

48. • The eluted Ca ions increase the proliferation of human dental
pulp cells in a dose-dependent manner (Clapham 1995, Takita
et al. 2006).
• In addition, Ca ions specifically modulate osteopontin and
bone morphogenetic protein-2 levels during pulp calcification
(Rashid et al. 2003),
• The release of Ca enhances the activity of pyrophosphatase,
which helps to maintain dentine mineralization and the
formation of a dentine bridge (Estrela & Holland 2003).

49. 3- Flowable composites
Composites with a lower
amount of filler  more fluid
consistency, less strength and
lower modulus

50. 4- Glass ionomers
Renewable source of
fluoride under
restorations
Reduce the
incidence of
caries
Fluoride
Glass ionomer cements (GIC):
 Bond to tooth structure
 Act as a thermal barrier
 Ability to bond in a moist environment
 Easy to use.
 Anticariogenic.

51. Light-cured resin-modified glass
ionomers (RMGIs)
 Provide good adhesion to both tooth structure
and restorative materials
 High strength
 Flexible (low modulus of elasticity)
 Dual-setting reaction:
1) Light-activated, methacrylate crosslinking
reaction
2) Slower, delayed, acid-base reaction
Which gives RMGIs an additional period of
maximum flexibility to absorb stress from the
adjacent shrinking composite.

52. BASES

53. Classification of bases
Protective
bases
Sedative bases Insulating bases
They protect the
pulp before
restoration is
placed
They help in calming the pulp
which has been irritated by
mechanical, chemical or
other means
They protect the
tooth from thermal
shock.
Bases should have sufficient strength so that they can withstand
forces of mastication and condensation of permanent
restorations.

54.  Excellent
sealing quality.
 Bacteriostatic
in nature.
 Anodyne
effect.
Reduces the thermal
conductivity of
metallic restorations
Blocks undercuts in
the preparation wall
in case of cast
restorations.
 Chemically
bonds to tooth
 Antibacterial
properties
 Fluoride release
 Anticariogenic
property
 Chemical
bond to tooth
 Well tolerated
by the pulp.
Materials used as bases
Zinc oxide
eugenol
Zinc phosphate
cement
Polycarboylate
cement
Glass ionomer
cement

55. Pulp Protection according with depth of tooth
preparation

56. Recent Materials used for Pulp Protection

57. Biodentin
Biodentine is a calcium-silicate based material.
Advantages:
 Biocompatible so no pulp inflammatory
responses
 Can be used wherever dentin is damaged
 Outstanding sealing properties
 Used as base or liner under composite
restorations
 Adequate compressive and flexural strength
 Creates faster dentin bridges
 Better properties than glass ionomer and
calcium hydroxide
 Radio opacity for following up

58. • Biodentine (Septodont, France) is a new calcium silicate–based restorative
cement with dentin-like mechanical properties, which can be used as a
dentin substitute on crowns and roots similar to how MTA is used .
• It has a positive effect on vital pulp cells and stimulates tertiary dentin
formation..
• In direct contact with vital pulp tissue, it also promotes formation of
reparative dentin.
• Biodentine consists of a powder and liquid.
• The powder mainly contains tricalcium and dicalcium silicate
(the principal component of Portland cement, as well as calcium carbonate
, Zirconium dioxide (ZrO2) serves as contrast medium.

59. • The liquid consists of calcium chloride, which is used as a setting
accelerator and water-reducing agent in aqueous solution with an admixture
of polycarboxylate (a superplasticizing agent)
• Biodentine may be successfully used as a posterior restoration material for
up to 6 months after direct pulp capping.
• After validation of pulp health, it may be partially removed to place a
permanent composite material
Response of Human Dental Pulp Capped with Biodentine and Mineral Trioxide Aggregate -
Alicja Nowicka JOE2013:39

61. (a & b) Pre-operative photograph showing in 11 with pulp exposure
(c) Preoperative radiograph
(d and e) A 3mm layer of Biodentine located over the uncovered pulp
(f) Immediate post-operative radiograph showing 3mm barrier of Biodentine
(g) Post-operative radiograph after 18 months showing a well-formed radio-
opaque barrier
(h) Post-operative recall photograph after 18 months
Clinical Procedure:

62. Mineral Trioxide Aggregate (MTA)
1) Characteristics:
 Non-toxic material
 Low or no solubility
 Stimulate reparative dentin development
by a normal defending process of an
early pulpal wound healing (evidence
was the presence of odontoblast like
cells)
 Minimal inflammation at early healing
stage
2) Composition:
a. Tricalcium silicate
b. Tricalcium aluminate
c. Tricalcium oxide
d. Silicate oxide

63. 3) Manipulation:
Mixed with sterile water in a 3:1 powder to liquid ratio
Setting time: MTA sets in 5 minutes
4) How does MTA work?
Tricalcium
oxide
Tissue fluids
Calcium
hydroxide
Hard tissue
formation

64. 5) Clinical procedure
a) Radiograph before performing the operative procedure
b) A Photograph that shows the uncovered pulp tissue
c) Photograph showing settlement of MTA above the pulp tissue
d) Radiograph after restoring the tooth permenantly
e) Six months follow up radiograph

65. Why is MTA better than Calcium Hydroxide?
MTA Calcium hydroxide
VS.
1. Rapid cell growth promotion in vitro
2. Greater ability to maintain the integrity of pulp tissue
3. Thicker and rapidly formed dentinal bridge
4. Less hyperemia
5. Lower level of necrosis

66. • Histological evaluations of exposed pulp tissue from animals capped with
MTA have shown the formation of a thicker dentinal bridge, with low
inflammatory response, hyperemia and pulpal necrosis compared to
calcium hydroxide cement.
• Calcium hydroxide does not adhere to dentine and lacks the ability to seal.
• Tunnel defects in dentine bridges under calcium hydroxide dressings can
act as pathways for microleakage (Cox et al. 1985). This material also has a
tendency to dissolve over time (Schuurs et al. 2000).
• MTA appears to induce the formation of a dentin bridge at a faster rate than
calcium hydroxide
Response of Human Dental Pulp Capped with MTA and Calcium
Hydroxide Powder- MLR Accorinte et al Operative Dentistry 2008:33

67. • The ability of MTA to induce the formation of a dentine bridge may be due
to its excellent sealing ability (Torabinejad et al or biocompatibility
(Kettering &Torabinejad1995).
• MTA can induce cytokine release from bone cells (Koh et al.1995)and can
allow the attachment of osteoblasts in the form of a monolayer.
Response of Human Dental Pulp Capped with MTA and Calcium
Hydroxide Powder- MLR Accorinte et al Operative Dentistry 2008:33

68. • Calcium hydroxide powder has a pH ranging from 11 to 13, while MTA
and calcium hydroxide cement possess a pH of approximately 10.
• The higher the pH of the material, the thicker the mummified zone, the
more complete the dentin bridge formation and the higher the inflammatory
infiltrate.
• Some question the superiority of calcium hydroxide, because of its
degradation over time, tunnel defects through dentinal bridges under it and
poor sealing properties
• MTA has sufficient compressive strength to allow condensing of amalgam
and a negligible solubility (Torabinejad et al. 1995).
Response of Human Dental Pulp Capped with MTA and Calcium
Hydroxide Powder- MLR Accorinte et al Operative Dentistry 2008:33

70. Thercal
2) Composition:
Tricalcium silicate particles in a hydrophilic monomer that provides significant
calcium release making it a uniquely stable and durable material as a liner or base.
3) Mechanism:
Calcium release stimulates hydroxyapatite and secondary dentin bridge formation
4) Indications:
Any pulpal exposures (carious exposures, mechanical exposures or traumatic
exposures )
1) Characteristics:
TheraCal is a light cured, resin modified
calcium silicate filled liner designed for use in
direct and indirect pulp capping, as a protective
base/liner under composites, amalgams,
cements, and other base materials.

71. Clinical Procedure

72. Why is Thercal better than MTA & Calcium Hydroxide?
MTA Calcium hydroxideThercal
VS.
 Higher calcium releasing ability
 Lower solubility than either MTA or Calcium Hydroxide due to
the capability of TheraCal to be cured to a depth of 1.7 mm
which avoids the risk of dissolution.

73. • Thera-Cal proved to be an ion-leaching material able to release calcium and
hydroxyl ions for a period of at least 28 days, and it released significantly
more calcium than either ProRoot MTA or Dycal throughout the test
period.
• The findings of this study suggest that the resin portion of TheraCal
(comprising hydrophobic and hydrophilic monomers) is able to
promote/sustain Ca and OH ion release within the wet surgical site (on the
tooth pulp and/or dentine) and could favour the interaction of the
formulation with the hydrophilic tooth dentine.
Chemical–physical properties of TheraCal, a novel light-curable MTA-like
material for pulp capping- M. G. Gandolfi IEJ 2012:45

74. • Most recent studies report long term success rates close to 90% for laser
assisted pulp capping , compared to a success rate of about 60 % with
traditional methods.
• The use of the Er,Cr:YSGG laser allows cavity preparation to be completed
with only one instrument in contrast to alternate use of high and low speed
rotary instruments and other laser wavelengths ( CO2, Nd:YAG and diode
lasers) which cannot be used for ablation of hard tissue.
Lasers in pulp capping
Erbium chromium laser in pulp capping treatment – dr.giovanni J Oral laser application
2006;6

75. • CO2 and erbium lasers are more superficial in their interaction with tissue
than the diode and Nd: YAG wavelengths which penetrate more deeply and
have a greater capacity for scattering .
• Coagulating effect of laser guarantees a dry operating area with no bleeding
and creation of zone of necrosis that is more superficial compared to
chemical pulp capping agent.
• Only erbium laser limits a pressure increase in dental cavity thus avoiding
the risk of pushing either mechanically or manually infected dentinal chips
into the pulp tissue during caries removal.
Erbium chromium laser in pulp capping treatment – dr.giovanni J Oral laser application
2006;6

80. Caster Oil Bean (COB) Cement
Histological sections
comparing the rate of
regeneration between
calcium hydroxide and
COB indicating that the
regeneration is faster with
COB
The castor oil bean (COB) (Ricinus communis) is a polyester formed by an amino radical
which was initially developed as a biomaterial for bone repair and regeneration after local
bone injury.
Advantages:
Confers bactericidal effect
Has biocompatibility with living tissues.
It has great potential to facilitate tissue
healing
Excellent structural properties,
Low cost
Good physicochemical properties

81. Dental pulp engineering and regeneration

82. • Although the concept of engineering a whole tooth offers exciting
potential and has been shown to be potentially feasible in controlled
in vivo animal models, but significant clinical challenges remain.
• Issues surrounding the control of tooth shape, size, availability of
dental epithelium, growth, and eruption of an engineering bio-tooth
have yet to be resolved
• Investigations are currently in progress to develop methods to
engineer a whole tooth and dental pulps.
Review :Dental pulp stem cells: what, where, how?- ALASTAIR J. SLOAN
International Journal of Paediatric Dentistry 2009; 19

83. • These range from tissue recombination studies to more complex
scaffold-based engineering strategies, assembly of different
bioengineered components, novel cell pellet engineering,
chimeric tooth engineering, and gene-manipulated tooth
regeneration.
• Regeneration of the dental tissues provides an attractive
alternative to more traditional restorative approaches because
the diseased tissue is replaced by natural tissue, which forms an
integral part of the tooth.
• The development of such approaches, however, requires precise
regulation of the regenerative events if they are to be effective.
Review :Dental pulp stem cells: what, where, how?- ALASTAIR J. SLOAN
International Journal of Paediatric Dentistry 2009; 19

84. Clarity on the biology of caries, comprehension of technological advances
and conviction about enhanced restorative products has initiated pulp
preservation that indeed is a benefit to the clinician and the patient.
Science is a mystery that we won’t ever stop trying to reveal
its secrets so what’s the next material we’ll discover?

85. References
• Sturdevant’s Art and science of operative dentistry 5th edition
• Ingle’s endodontics 6th edition
• Philips science of dental materials – 5th south asia edition
• Text book of operative dentistry – vimal k sikri 4th edition
• Quoted Articles
• Internet sources