ENDODONTIC IRRIGANTS

SEMINAR

1. SEMINAR
ENDODONTIC
IRRIGANTS
DR . KARUNA SHARMA
POST GRADUATE STUDENT

2. INTRODUCTION
OBJECTIVES OF IRRIGATION
PROPERTIES OF IDEAL SOLUTION
VARIOUS ROOT CANAL IRRIGANTS USED
RECENT ADVANCES
IRRIGATION DEVICES AND TECHNIQUE
CONCLUSION
CONTENTS

3. INTRODUCTION

4. Bacteria have long been recognized as the primary
etiologic factors in the development of pulp and
periapical lesions.
Successful root canal therapy depends on
thorough chemomechanical debridement of pulpal
tissue, dentin debris, and infective microorganisms.

5. Irrigants can augment mechanical debridement by
flushing out debris, dissolving tissue, and
disinfecting the root canal system.
Chemical debridement is especially needed for
teeth with complex internal anatomy such as fins or
other irregularities that might be missed by
instrumentation.

6. The smear layer consists of
organic and inorganic substances
as well as fragments of
odontoblastic processes, various
species of bacteria and necrotic
debris.
SEM of dentinal tubules
containing microorganisms.

8. PROPERTIES OF IDEAL SOLUTIONS
1.Broad antimicrobial spectrum
2.Mechanically flushes out the debris from the root
canal
3.Ability to dissolve necrotic pulp tissue remnants
4. Serves as a lubricant
5. Removes the smear layer
6. Nontoxic and biocompatible in nature
7. Low surface tension

9. ROOTCANALIRRIGANTSUSED

10. CLASSIFICATION
According to Kandaswamy D, Venkateshbabu N

13. Saline
I.Sterile.
II.Causes less apical tissue damage
Disadvantage :
Very less dissolving property and
antibacterial activity.

14. HYDROGEN PEROXIDE

15. Most commonly used irrigant(it is used mainly in
combination with NaOCl).
2 modes of action
Effervescence effect
Which pushes out the tissue debris against the
gravity.
The bubbling of solution when it comes in contact
with the tissue and certain chemicals physically
removes debris from the canal.
Hydrogen Peroxide

16. Nascent O
2
Destroys strictly anaerobic
microorganisms.
H
2O
2 is less effective as a solvent,
so less damage to periapical tissue.
H
2O
2shouldn't be the last irrigant used in a canal,
because nascent oxygen may remain and cause
pressure. Therefore NaOCl should be used to react
with H
2O
2and liberate the remaining oxygen.

17. I.When procedural accidents have occured in
either the root or floor of the pulp chamber
Perforation
II.when apical constriction has been destroyed
with severe pericementitis.
Indications

19. APPEARENCE
Clear straw colored solution containing 5% of chlorine
is the most widely used irrigating solution
NaOClon ionization produces hypochlorousion
and hypochlorite ion
these are responsible for the antimicrobial
activity of NaOCl

20. CONCENTRATION
0.5% -5.25% is an effective concentration for
use as an irrigantin the root canal. Of a no. of
solutions studied none was more effective than a
5.2% solution of sodium hypochlorite.
2.5% NaOClis a commonly employed
concentration as it decreases the potential for
toxicity while maintaining tissue dissolving and
antimicrobial activity.

21. The decrease in concentration is safer but
reduces the effectiveness of the irrigants.This
can be compensated by :
1.Increasing the volume of the irrigant
employed
2.Increasing the duration of irrigation
3.Warming the irrigantincreases the
effectiveness (chairsideirrigantwarming
devices)

22. 4. Passive ultrasonic activation of the irrigant
(Increases the effectiveness as well as enable the
irrigant to reach the complex isthmuses of the root
canal)
NaOCl completely dissolves an entire pulp in 20
minutes to 2 hours,
The pulp dissolving ability of this irrigant is useful
during the cleaning and shaping of inaccessible
areas such as the isthmus region and C shaped
canal systems

23. TEMPERATURE
60 Degree of warm water is taken in a
water bath and place sodium
hypochlorite in this warm water before
use.
SHELF LIFE
5.25 % --------------------10 WEEKS
2.6 % ---------------------1 WEEK.

24. MECHANISM OF ACTION
SAPONIFICATION REACTION
NaOClacts as an organic and fat solvent,
degrading fatty acids and transforming them
into fatty acid salts (soap) and glycerol (alcohol),
which reduces the surface tension of the
solution

25. AMINOACID NEUTRALIZATION
REACTION-
NaOCl neutralizes amino acids forming water
and salt.

26. When hypochlorousacid, a substance present in
NaOClsolution, comes in contact with organic
tissue it acts as a solvent and releases chlorine,
which combines with the protein amino group to
form chloramines.
Hypochlorousacid (HOCl
−
) and hypochlorite
ions (OCl
−
) lead to amino acid degradation and
hydrolysis.
CHLORAMINATION REACTION
The chloraminationreaction between
chlorine and the amino group (NH) forms
chloramines that interfere in cell metabolism.

28. Chlorine (a strong oxidant) has an
antimicrobial action, inhibiting bacterial
enzymes and leading to an irreversible
oxidation of essential bacterial enzymes.
Thus, the saponification, amino acid
neutralization, and chloramination reactions
that occur in the presence of microorganisms
and organic tissue lead to the antimicrobial
effect and tissue dissolution process.

29. Antimicrobial properties of NaOClis due to
the destruction of the bacteria which takes
place in two phases
1.Penetration in bacterial cell wall
2.Chemical combination with the
protoplasm of the bacterial cell and
disruption of DNA synthesis.

30. IncreasingtheefficacyofNaOCl
1.Alteringtheph
a.Theantibacterialpropertiesandtissue-
dissolvingpropertiesof5.25%NaOCldecrease
whenitisdiluted.
Inaqueoussolution,hypochlorousacidpartially
dissociatesintotheanionhypochlorite(OCl
−
):
NaOCl+H
2O NaOH+HOCl

31. The 'available' chlorine is the sum of the
HOCland OCl
−
concentrations in the solution.
Available chlorine might be defined as a
measurement of oxidizing capacity and is
expressed in terms of the amount of
elemental chlorine.
HOClis considered to be a stronger
oxidant than the hypochlorite ion.

32. The HOClmolecule is responsible for the
strong chlorinating and oxidizing action on
tissue and microorganisms.
HOCldissociation depends on pH, with the
clinical equilibrium between HOCland OCl
−
being maintained as HOClis consumed through
its germicidal function.
Bakergave the relationship between HOCl,
OCl
−
, and pH.

33. At pH 10, basically all chlorine is in the OCl
−
form; the reverse occurs at a pH of 4.5, when
all chlorine is in the form of HOCl.
The disinfecting properties decrease with
higher pH, paralleling the concentration of
dissociated HOCl.
Bloomfield and Miles ,1979, confirmed that
hypochloritesat a lower pH possess greater
antimicrobial activity.

34. Andrews and Orton,1904, reported that
HOClwas responsible for the destruction
of microorganisms.
Morris,1966, found that OCl
−
ion
possesses approximately 1/80
th
of the
germicidal potency of HOClin killing
Escherechiacoli.

35. Reactive chlorine in aqueous solution at body
temperature can take two forms: hypochlorite
(OCl
−
) or hypochlorousacid (HOCl).
1 mol of hypochlorite contains 1 mol of available
chlorine.
The state of available chlorine is dependant on
the pH of the solution.
Above a pH of 7.6, the predominant form is
hypochlorite and below this value it is
hypochlorousacid.

36. Both forms are extremely reactive
oxidizing agents.
Pure hypochlorite solutions, as are used in
endodontics, have a pH of 12, and thus
the entire available chlorine is in the form
of OCl
−
.
However, at identical levels of available
chlorine, HOClis more bactericidal than
hypochlorite.

37. 2. Temperature
A rise in temperature by 25°C increased
NaOClefficacy by a factor of 100.
The capacity of a 1% NaOClat 45°C to
dissolve human dental pulps was found to be
equal to that of a 5.25% solution at 20°C.

38. 3. Ultrasonic
The use of ultrasonic agitation increased the
effectiveness of 5% NaOClin the apical
third of the canal wall.
Passive ultrasonic irrigation with a nickel-
titanium tip produced superior tissue-
dissolving effects as compared to sonic
irrigantactivation.

39. DISADVANTAGES:
Toxic to living tissue and caustic effects on
healthy periradiculartissues on inadvertent
extrusion during the irrigating procedure.
Such sodium hypochlorite accidents are the
reason for lower concentration 0.5 to 1% or 2.5%
NaOClbeing more commonly preferred by
clinicians.
It does not remove the inorganic component of
the endodontic smear layer.
Unpleasant Taste
Corrosive nature

40. Extrusion of NaOCl into periapical tissues can
cause severe injury to the patient.
To minimize NaOCl accidents, the irrigating
needle should be placed short of the working
length, fit loosely in the canal and the solution
must be injected using a gentle flow rate.
Constantly moving the needle up and down during
irrigation prevents wedging of the needle in the
canal and provides better irrigation.
The use of irrigation tips with side venting
reduces the possibility of forcing solutions into the
periapical tissues.

41. Treatment of NaOCl accidents is palliative
and consists of observation of the
patient as well as prescribing antibiotics
and analgesics.

42. NaOCl was
inadvertently expressed
into the periapical tissues
through the apical
foramen of the right
maxillary cuspid during
cleaning and shaping.
No treatment
was necessary for the
hematoma and swelling.

43. Glyoxide
( Glycerol + Carbamideperoxide)
Carbamideperoxide is available in an anhydrous
glycerol base to prevent decomposition and is a useful
irrigant.
ADVANTAGES
Better tolerated than NaOCl
Greater solvent action
More germicidal than H2O2.
Excellent irrigant
Best use in narrow or curved canals, utilizing the
slippery effect of the glycerol.


44. Glyoxidemore viscous with a high
surface tension
According to weineGlyoxideas a major
irrigantshould be used in small canals
until size 20 is reached and then switch to
NaOCl.

45. Chlorhexidine is a potent antiseptic, which is widely used
for chemical plaque control in the oral cavity.
Aqueous solutions of 0.1 to 0.2% are recommended for
that purpose, while 2% is the concentration of root canal
irrigating solutions .
It is commonly held that chlorhexidine would be less
caustic than sodium hypochlorite.
However, that is not necessarily the case. A 2%
chlorhexidine solution is irritating to the skin.
.
Chlorhexidine digluconate

46. As with sodium hypochlorite, heating a
chlorhexidine irrigant of lesser concentration could
increase its local efficacy in the root canal system
while keeping the systemic toxicity low.

47. Chlorhexidine gluconate :
Causes cytoplasmic precipitation or coagulation
on the cell wall.
Disadvantages :
(a) chlorhexidine is unable to dissolve
necrotic tissue remnants, and
(b) chlorhexidine is less effective on Gram-
negative than on Gram-positive bacteria.

50. CHELATING AGENTS

51. CHELATING AGENTS
PURPOSES
LUBRICATION
EMULSIFICATION
HOLDING DEBRIS
CHELATORS AVAILIBILITY
VISCOUS SUSPENSION
AQUEOUS SUSPENSION

52. Viscous suspension
Advantageously promotes the emulsification of
organic tissue
Facilitates the negotiation of the canal
Best used for holding debris in liquid
suspension.
Aqueous suspension
For finishing the preparation
Removes the smear layer

53. EDTA (Ethylene-di amine-tetra acetic acid)
Nygard OstbyFirst suggested the use of EDTA
For cleaning and widening canals.
MECHANISM OF ACTION
Forms a calcium chelate solutionwith the calcium ion of dentin,
Dentin thereby becomes more friable and easier to instrument.
USES
Cleaning and shaping of the root canal
Effective for achieving canal patency,Enlargement, Debridement
Disinfection.

54. FORMULA
Disodium salt of EDTA : 17.0 g
Distilled water : 100.0ml
5N Sodium hydroxide : 9.25 ml

55. EFFECTS
Softens dentin
Antimicrobial properties.
Moderate degree of irritation.
No deleterious effect when used clinically as an
irrigating solution.
Removes smear layer.

56. Effects partial demineralization of dentin to a
depth of 20 to 30 m in 5 minutes.
The extent of demineralization of EDTA is
proportional to the exposure time.
Optimum working time of EDTA –15 minutes,
Should perhaps be renewed in the canal each 15
minutes.

58. EDTAC
Addition of cetavlon(0.84 gm), a quaternary
ammonium compound to EDTA produces a solution
called EDTAC
Properties
Greater germicidal activity
Greater inflammatory potential to tissue as well.

60. Citric acid and EDTA-T
The use of 10% citric acid as final irrigation has
shown good results in smear layer removal. In
vitrostudies have shown their cytotoxicity, and
10% citric acid has proven to be more
biocompatible than 17% EDTA-T and 17% EDTA.
Scelza et alevaluated the inflammatory response
of 17% EDTA, 17% EDTA-T, and 10% citric acid in
bony defect created in rat jaws and they
concluded that 10% citric acid showed less
aggressive in inflammatory response.

61. Maleic acid
Maleic acid is a mild organic acid used as an acid
conditioner in adhesive dentistry.
Ballal et al. reported that final irrigation with 7%
maleic acid for 1 min was more efficient than 17%
EDTA in the removal of smear layer from the
apical third of the root canal system.

62. HEBP
HEBP (1-hydroxyethylidene-1, 1-
bisphosphonate), also known as etidronic acid or
etidronate, has been proposed as a potential
alternative to EDTA or citric acid because this
agent shows no short-term reactivity with NaOCl.
HEBP is nontoxic and has been systematically
applied to treat bone diseases.
The demineralization kinetics promoted by both
9% HEBP and 18% HEBP were significantly
slower than those of 17% EDTA.

63. MTAD :
A new solution for the removal of the smear
layer.
 Mixture of Tetracycline isomer
(Doxycycline)
 Acid(citric acid)
 Detergent(Tween 80).

64. Antibacterial activity and smear
layer removal
MTAD is composed of three constituents that are
expected to act synergistically against bacteria.
The bactericidal effect of MTAD was inferior to
1%-6% NaOCl against E faecalisbiofilms.
The antibacterial activity of MTAD might also be
inhibited by the buffering effect of dentin and the
serum albumin present in the root canal.
MTAD has been reported to be effective in
removing smear layer.

65. In the MTAD preparation, the citric acid may
serve to remove the smear layer, allowing
doxycycline to enter the dentinal tubules and
exert an antibacterial effect.
The recently revised protocol for clinical use
of MTAD advises an initial irrigation for 20
min with 1.3% NaOCl, followed by a 5-min
final rinse with MTAD.

66. TetracyclineincludingTetracyclineHCl,MinocyclineandDoxycyclineareBroad
SpectrumAntibioticsthatareeffectiveagainstawiderangeof
microorganisms.
Mechanismofactionoftetracyclin:
Bacteriostaticinnature:
Thispropertymaybeadvantageousbecauseintheabsence
ofbacterialcelllysis,antigenicbyproducts(i.e.Endotoxins)arenot
released.
LowpH:
itcanactasacalciumchelatorandcauseenamelandroot
surfacedemineralization.
Tetracycline

67. Substantive medication:
Absorbed and is gradually released from tooth
structures such as dentin and cementumand
have prolonged effect.
It significantly enhances healing after surgical
periodontal therapy.
Similar attempts with penicillin and
erythromycin were ineffective.
DETERGENT (TWEEN 80 )
Role of the detergent is to lower the surface
tension and increase the generating ability of the
irrigating solution.

68. Doxycyclineand Citricacidwere
effectiveinremovalofsmearlayerwhen
usedfor1to5minutes.
Acid :

69. Tetraclean
®
Tetraclean is a mixture of doxycycline hyclate (at a
lower concentration than in MTAD 50 mg/5ml), an
acid, and polypropylene detergent.
It is able to eliminate microorganisms and smear
layer in dentinal tubules of infected root canals with
a final 5-min rinse.
Comparison of antimicrobial efficacy of 5.25%
NaOCl, MTAD, and Tetraclean
®
against E faecalis
biofilm showed that only 5.25% NaOCl could
consistently disgregate and remove the biofilm at
every time interval.

70. However, treatment with Tetraclean
®
caused a
high degree of biofilm disgregation in every
considered time interval (5, 30, and 60 min at
20°C) as compared with MTAD.

71. Herbal
Triphala
Triphalaconsists of dried and powdered fruits of
three medicinal plants Terminalia bellerica,
Terminalia chebula, and Emblica officinalis. Triphala
achieved 100% killing of E faecalisat 6 min.
This may be attributed to its formulation, which
contains three different medicinal plants in equal
proportions; in such formulations, different
compounds may help enhance the potency of the
active compounds, producing an additive or
synergistic effect.

72. Triphalacontains fruits that are rich in citric acid,
which may aid in removal of the smear layer.
The major advantages of using herbal alternatives
are easy availability, cost-effectiveness, longer shelf
life, low toxicity, and lack of microbial resistance.

73. Green tea
Green tea polyphenols, the traditional drink of
Japan and China is prepared from the young
shoots of the tea plant Camellia sinensis.
Green tea polyphenols showed statistically
significant antibacterial activity against E
faecalisbiofilm formed on tooth substrate. It
takes 6 min to achieve 100% killing of E
faecalis.

74. Morinda citrifolia
Morinda citrifolia (MCJ) has a broad range of therapeutic
effects, including antibacterial, antiviral, antifungal,
antitumor, antihelmintic, analgesic, hypotensive, anti-
inflammatory, and immune-enhancing effects.
MCJ contains the antibacterial compounds L-asperuloside
and alizarin .
Murray et al proved that, as an intracanal irrigant to remove
the smearlayer, the efficacy of 6% MJC was similar to that
of 6% NaOCl in conjunction with EDTA. The use of MCJ as
an irrigant might be advantageous because it is a
biocompatible antioxidant and not likely to cause severe
injuries to patients as might occur through NaOCl accidents.

80. IRRIGATION DEVICES AND TECHNIQUES
Conventional
•Syringes
•Needles
EndoActivator
•It is based on sonic vibration (up to 10,000
cpm) of a plastic tip in the root canal
EndoVac
•, the EndoVacsystem is based on a negative-
pressure approach whereby the irrigantplaced in
the pulp chamber is sucked down the root canal and
back up again through a thin needle with a special
design

81. Syringes
Plastic syringes of different sizes (1–20 mL)
are most commonly used for irrigation.
Although large-volume syringes potentially allow
some time-savings, they are more difficult to
control for pressure and accidents may happen.
Therefore, to maximize safety and control, use
of 1-to 5-mL syringes is recommended instead
ofthe larger ones.

82. •Because of the chemical reactions between
many irrigants, separate syringes should be
used for each solution
Needles
Although 25-gauge needles were commonplace
for endodontic irrigation, they were first
replaced by 27-G needles, now 30-G and even
31-G needles are taking over for routine use in
irrigation.

83. IRRIGATION TECHNIQUE

84. ThebarreltipshouldbeaLeurLokdesign,
ratherthanfrictionfittopreventaccidental
needledislodgementduringirrigation.

85. The needle should be bent to an obtuse angle, to
reach the canals of posterior as well as anterior
teeth.
The needle is inserted into the root canal so
that it does not binds.

86. Sufficientroombetweenneedleandcanal
wallallowsforthereturnflowofthesolution
andavoidsforcingofsolutionintotheperiapical
tissue.

87. If needle does not bind, the solution
should be ejected from the syringe with
little or no pressure on the plunger.

88. NEEDLE IN ROOT CANAL.
INJECTION OF IRRIGATING SOLUTION.

89. In narrow root canals, the tip of the
needle is placed in the root canal and the
irrigant is discharged until it fills the pulp
chamber.
RETURN OF SOLUTION IS COLLECTED ON
-GAUGE PIECE
-ASPIRATED

90. Drying should be done with absorbent
points.
Most of the residual irrigating solution
may be removed from the root canal by
holding the needle of the syringe in the
canal and withdrawing the plunger slowly.
Compressed air must not be used for
drying the root canal because tissue
emphysema may result if an air bubble
penetrates the periapical tissue.

91. DIFFERENT IRRIGATING NEEDLES USED
 BEVELED NEEDLE.
 MONOJECT TIP.
 SAFE ENDED TIP.
 BEVELLED NEEDLE:
IN BEVELED NEEDLE IRRIGANT IS
FORCED APICALLY. THERE IS RISK OF
EXTRUSION IF NEEDLE BECOMES LODGED
IN THE CANAL.

92. MONOJECT TIPS:
ADVANTAGE OF PASSING
IRRIGANT TO THE SIDE.
SAFE ENDED TIP:
BEST TIP ADVANTAGE OF PASSING
IRRIGANT TO THE SIDE.

93. Advanced Irrigating Needle
Max I Probe Needle
or
Pro Rinse

94. Max I probe irrigates
through side vent and the
apical end of the probe is
closed.
It consists of 25, 28 and
30 gauge closed ended
needles.
Advantages:
Prevents accidental
forcing of irrigating solution
into periapical tissue

95. Richman in 1957 was the first to use ultrasonic
scaler for apicoectomies.
Martin designed a commercial system harnessing
the ultrasonic energy for the preparation and cleaning
the root canal in 1976.
This technique was termed
endosonics.
Ultrasonics :

96. ACTION OF ACOUSTIC STREAMIG :
The acoustic streaming generated by the file help to
reduce the number of bacteria in the canal by removing
the smear layer and debris harboring bacteria, thereby
facilitating their mechanical removal.
Acoustic streaming

97. Surface treated with
EDTA
Surface treated with
ULTRASONICS

98. Flexi-Glide Utility Tips
Vista Dental's Flexi-Glide Utility Tips are disposable
tips that are ideal for irrigation, application, and micro-
aspiration. Constructed of polyimide tubing, Flexi-
Glide's flexible, crimp-resistant tip facilitates access
and provides maximum reach during canal procedures.


99. EndoActivator
•is a new type of irrigation facilitator. It is based on
sonic vibration (up to 10,000 cpm) of a plastic tip in
the root canal.
•The system has 3 different sizes of tips that are
easily attached (snap-on) to the handpiecethat
creates the sonic vibrations
•The use of EndoActivatorfacilitates irrigant
penetration and mechanical cleansing compared with
needle irrigation, with no increase in the risk of irrigant
extrusion through the apex.

100. MULTIPLE BENEFITS
SAFE
Strong, flexible medical grade polymer tips
Single patient use
Uncoated & non cutting tips
EFFECTIVE
Create fluid hydrodynamics
Improves debridement and the disruption of thesmear layer and
biofilm
SIMPLE
Very simple clinical technique
Ideal in practice when portability is required

101. EndoVac
the EndoVacsystem is based on a negative-
pressure approach whereby the irrigantplaced
in the pulp chamber is sucked down the root
canal and back up again through a thin needle
witha special design

102. Master delivery tip
(MDT) suction tubing
High volume
suction
Macro cannula and
Micro cannula tubing
Macro cannula
Micro cannula
Master delivery tip
EndoVac adaptor

103. During irrigation, the Master Delivery Tip delivers
irrigant to the pulp chamber and siphons off the
excess irrigant to prevent overflow.
Both the Macro-Cannula and MicroCannula exert
negative pressure that pulls fresh irrigant from the
chamber, down the canal to the tip of the cannula,
into the cannula, and out through the suction hose.
Thus, a constant flow of fresh irrigant is delivered
by negative pressure to working length.

104. advantages
1-the EndoVacsystem lowers the risks
associated with irrigation close to the apical
foramen considerably.
2-Another advantage of the reversed flow of
irrigantsmay begood apical cleaning at the 1-
mm level and a strong antibacterial effect
when hypochlorite is used

107. References
1.GROSSMAN Twelfth edition
2.GEN DENT.2001, May-Jun; 19[4];272 –281
3.J ENDOD. 2003 ,Mar ;29[3]; 170-175
4.TEXT BOOK OF ENDODONTICS –INGLE
5.PATHWAYS OF PULP –COHEN
6.PRACTICE OF ENDODONTICS -WALTON

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