Download Pulpal Irritants and Dentin

Pulpal Irritants and Dentin-Pulp
Reactions
Presented by: Dr. Reza Hatam
Dental pulp as a connective tissue:
How respond to irritants?
What makes it prone to degeneration?
Unique environment of dental pulp
• Unyielding walls of dentin
• Resistant and resilient fiber-reinforced ground
substance
• Does not have a consistent effective collateral
circulation
Pulpal Reactions
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Caries
Local Anesthetics
Restorative Procedures
Dental Materials
Vital Bleaching
Periodontal Procedures
Orthodontic Movement
Permeability of Dentin
The role of odontoblasts
Hydrodynamic Theory
Pulpal Reaction to Caries
• Decrease in dentin permeability
• Tertiary dentin formation
• Inflammatory and immune reactions
Formation of Sclerotic Dentin
Bioactive Molecules Sequestered
During Dentinogenesis
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Heparin-binding growth factor
Transforming growth factor (TGF)-β1, β3
Insulin-like growth factor
Platelet-derived growth factor
Bone morphogenetic protein (BMP)
• The TGF-β super family in particular seems to
be important
Formation of Tertiary Dentin
Pulpal Immune Response
• The early inflammatory response is
accumulation of chronic inflammatory cells
Dental caries stimulates the accumulation of
pulpal dendritic cells in and around
odontoblastic layer
Calcium hydroxide produces an inflammatory
response that stimulates dentinal bridge
formation
The high PH can liberate bioactive molecules
Vital Pulp Therapy
Definition
“Treatment initiated to preserve and maintain
pulpal tissue in a healthy state, tissue that has
been compromised by caries, trauma or
restorative procedures’’
Goals of pulp therapy
Primary objective is to maintain
the integrity and health of
the oral tissues
• Stimulate the formation of reparative dentin to retain the tooth
as a functional unit
• Apexogenesis of the immature permanent tooth
Correct diagnosis - important in planning for
treatment
Reversible pulp
Irreversible pulp
pathosis
pathosis
Aim – preservation of pulp vitality
Potentially Reversible
Pain
Momentary-dissipates readily
after stimulus is removed
(e.g. cold)(A- fiber
stimulation
Probably Irreversible
Continous-persists for minutes to
hours after stimulus is
removed;presence of
internal(secondary) irritant (C fibers
stimulation)
Throbbing-may be present;due to
arterial pulsation in area of increased
pulpal pressure(C fibers stimulation)
Stimulus
Requires external stimulus
Spontaneous does not require
external stimulus; dead or injured
pulp tissue present in chamber or
canal
Intermittent-spontaneous pain of
short duration
History
Patient may have undergone
recent dental procedures
Patient may have had extensive
restoration, pulp capping, deep
caries or trauma
Potentially Reversible
Probably Irreversible
Electric pulp
test
May be premature response
May be premature, delayed or
mixed response
Percussion
Negative response
May respond in advanced stages
of pulpitis when concomitant acute
apical periodontitis is present
Lying down
Negative because of minimally Common finding because increase
affected pulp tissue
in cephalic blood pressure
increases already excessive
intrapulpal pressure
Color
Negative
May be present as a result of
tissue lysis and intra pulpal
hemorrhage
Radiograph
Probable cause (e.g.
restoration or caries)
Probable cause (e.g. restoration or
caries)
Peri-apex negative
Peri-apex- may be slight widening
of apical periodontal space
Treatment Modalities
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Indirect pulp capping therapy
Direct pulp capping therapy
Pulpotomy
Pulpectomy
Apexogenesis
Apexification
Definition
Indirect pulp capping therapy
The procedure involving a tooth with a deep carious lesion
where carious dentin removal is left incomplete, and the
decay process is treated with a biocompatible material for
sometime in order to avoid pulp tissue exposure
Indirect Pulp Capping Therapy
Rationale
Outer layer
Inner layer
•Irreversibly denatured
•Reversibly denatured
•Non remineralizable
•Remineralizable
•Infected
•Not infected
•Should be removed
•Should be preserved
Three dentinal layers encountered in active
caries
Necrotic, soft brown, teeming with
bacteria and not painful to remove
Firm but still softened discolored dentin
with fewer bacteria, painful to remove
Sound dentin, discolored area, minimal amount
of bacteria, painful to instrumentation
Indirect Pulp Capping Therapy
Objectives
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Arrest the carious process
Remineralization of carious or pre-carious dentin
Reduction in anaerobic bacteria
Formation of reparative dentin
Vital pulp maintenance
Continued normal root closure
Indirect Pulp Capping Therapy
Indications
Pain history
– No extremes
– May be associated with eating specially carbohydrates
– Sometimes dull
Clinical examination
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Large carious lesion
Normal mobility
No gingival pathologic condition
Normal color of tooth
Radiographic examination
– Probable carious exposure
– Normal peri-apical tissues
Indirect Pulp Capping Therapy
Contraindications
Pain history
– Sharp, penetrating pulpalgia indicating acute pulp inflammation
and/or necrosis
– Prolonged night pain
Clinical examination
– Mobility of tooth
– Discoloration of tooth
– Negative reaction to electric pulp testing
Radiographic examination
– large carious lesion producing definite pulp exposure
– Interrupted lamina dura
– Widened periodontal ligament space radiolucency
Procedure
First appointment
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Isolation with rubber dam
Cavity outline with high speed water spray hand piece
Remove superficial debris and soft necrotic dentin with slow speed
hand piece and large round burs, but do not expose the pulp
Potentially exposed site is covered with a commercial hard set
calcium hydroxide or other capping material.
Seal the cavity for 1-3 months
Procedure
Second appointment
Between appointment history should be negative and restoration intact
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Take bitewing radiograph-sclerotic dentin
Isolation
Carefully remove temporary dressing
Remaining carious dentin “flaky” and easily removed
Calcium hydroxide dressing
Reinforced zinc oxide eugenol or glass ionomer cement
Evaluation of therapy
• Minimally 1-3 months – to produce adequate
remineralization of the cavity floor
• Good long lasting seal of restoration
• Tooth asymptomatic
1.
Carious decalcified dentin
2.
Rhythmic layers of irregular
reparative dentin
3.
Regular tubular dentin
4.
Normal pulp with slight increase
in fibrous elements
One step approach
• 1. local anesthetic
• 2. Isolation
• 3. Removal of caries at enamel-dentine
junction.
• 4. Judicious removal of soft, deep carious
dentin
• 5. placement of lining material
• 6. final restoration
The major difficulties
• Determine at what point excavation halt
• Voids under restorative material
• Restoration failure and reactivation of lesion
Definition
Direct pulp capping therapy
“treatment of an exposed vital pulp by sealing the pulpal wound with a
dental material placed directly on a mechanical or traumatized
exposure to facilitate formation of reparative dentin and maintenance
of vital pulp.”
• During cavity preparation
• Traumatic injury
• Due to caries
Direct Pulp Capping Therapy
Contraindications
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Severe toothaches at night
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Spontaneous pain
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Tooth mobility
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Thickening of periodontal ligament
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Radiographic evidence of pulp or peri-radicular degeneration
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Excess of hemorrhage at the time of exposure
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Purulent or serous exudate from the exposure
Clinical success
• Maintenance of pulp vitality
• Absence of sensitivity or pain
• Minimal pulp inflammatory responses
• Absence of radiographic signs of dystrophic
changes
Direct Pulp Capping Therapy
Treatment considerations
• Debridement
• Hemorrhage and clotting
• Exposure enlargement
• Bacterial decontamination
• Medications and materials
Direct Pulp Capping Therapy
Medicaments
• Zinc oxide eugenol cement (Glass & Zander 1949)
• Corticosteroids and antibiotics
• Polycarboxylate cements
• Inert materials
– Isobutyl cyanoacrylate (Berkman 1971)
– Tricalcium phosphate ceramic (Heller 1975)
• Collagen fibers
• Formocresol
• Adhesive dentin bonding agents
Direct Pulp Capping Therapy –
calcium hydroxide
Herman 1930 , seltzer & Bender 1958
An ideal pulp capping material
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Stimulate reparative dentin formation
Maintain pulpal vitality
Release fluoride to prevent secondary caries
Bactericidal or bacteriostatic
Adhere to dentin
Adhere to restorative material
Resist forces during restoration placement
Sterile
Radiopaque
Provide bacterial seal
MTA
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Sustain alkaline PH after curing
Small particle size
Slow release of calcium ions
Induce pulpal cell proliferation and hard
tissue formation
• A gap free interface precludes microleakage
• Resist compression when final restoration
Partial pulpotomy
• “Surgical removal of small portion of the
coronal pulp as a means of preserving the
remaining coronal and radicular pulp”
Prognosis is extremely good (94-96%)
Definitions
Pulpotomy
“The complete removal of the coronal portion of the dental
pulp, followed by placement of a suitable dressing or a
medicament that will promote healing and preserve
vitality of the tooth”
this technique is advocated for deciduous teeth.
Caries Removal
• Dental dam isolation and Under magnification
and using dye are critical.
• Propylene glycol solution of Acid Red52.
• The retained caries affected of dentin allows
for remineralization by calcium phosphate
from pulp.
Hemostasis
• The one significant measurable variable to
predict the outcome.
• If hemostasis is not within 5-10 min,
diagnosis of irriversible pulpitis.
• Ferric sulfate, epinephrine, H2O2, NaOCL
• NaOCL clearance of dentin chips, biofilm
removal, chemical removal of blood cloth,
disinfection of the cavity
• Another emerging potential hemostatic agent
is MTAD
• An irrigant and antimicrobial agent for
removal of smear layer
• Doxycycline, acid citric and Tween 80
Postoperative Follow-up
• When MTA is used as pulp cap next visit can
be at 5-10 days. If treatment appears
successful next follow-up 6 weeks, then 6 and
12 months.
• In immature permanent teeth (apexogenesis)
the tooth compared with contralateral tooth.
Regenerative Endodontics
• The interplay among
stem cells
growth factors
scaffolds (biologic materials)
Future researches…