2. Introduction
• Every root canal system has spaces that
can not be cleaned mechanichally .
• The only way to clean webs, fins and
anastomoses is through effective use of
irrigation solution.
• in order to get the maximum efficiency
from irrigant , irrigant must reach the
apical portion of the canal .
8. Sodium hypochlorite (NaOcl)
Clear ,pale green-yellow liquid with
strong odor of chlorine .
It is a potent antimicrobial agent,
killing most bacteria instantly on
direct contact. It also effectively
dissolves necrotic and vital pulp
tissue.
The most advocated irrigant,inexpensive and readily available.
9. Sodium hypochlorite (NaOcl)
Anti microbial properties
Tissue solvent.
( dissolve vital and non vital tissue)
Flush debris.
Lubricant.
Eliminate the smear layer.
Low toxicity level.
10. Mechanism of action
Sodium hypochlorite (NaOCl) ionizes in water into Na and
the hypochlorite ion, OCl, establishing an equilibrium with
hypochlorous acid (HOCl).
Hypochlorous acid is responsible for the antibacterial
activity; the OCl ion is less effective than the undissolved
HOCl.
Hypochloric acid disrupts several vital functions of the
microbial cell, resulting in cell death.
11. Mechanism of action
At acidic and neutral pH, chlorine exists predominantly as
HOCl, whereas at high pH of 9 and above, OCl predominates.
12. Concentration
NaOCl is commonly used in concentrations between 0.5%
and 5%.
According to several studies The lower and higher
concentrations are equally efficient in reducing the number
of bacteria in infected root canals.
The time needed to inhibit bacterial growth and tissue
dissolving effect of NaOcl irrigant are related to it is
concentration ,but so is it is toxicity .
13. Increasing the temperature of hypochlorite irrigant
to 600C, significantly increased its antimicrobial and
tissue-dissolving effects.
Temperature
15. Sodium hypochloride accident
Immediate severe pain for 2-
6 minutes.
immediate edema in adjacent soft
tissue because of perfusion to the
loose connective tissue.
Extension of edema to a large site of
the face such as cheeks, peri- orbital
region, or lips.
Ecchymosis on skin or mucosa as a
result of profuse interstitial bleeding.
16. Sodium hypochloride accident
Management
inform the patient about the cause and
nature of the complication.
Immediately irrigate with normal saline
to decrease the soft-tissue irritation by
diluting the NaOCl.
Let the bleeding response continue as
it helps to flush the irritant out of the
tissues.
17. Sodium hypochloride accident
Recommend ice bag compresses for 24
hours (15-minute intervals)to minimize
swelling.
Recommend warm, moist compresses
after 24 hours (15-minute intervals).
pain control with strong analgesics for
3 to 7 days
19. Chlorhexidine (CHX)
Strong base, most stable in form of
its salt …Chlorohexdin gluconate.
It possesses a broad-spectrum
antimicrobial action and a relative
absence of toxicity.
CHX lacks the tissue-dissolving
ability.
21. Mechanism of action
It penetrates the cell wall and attacks the bacterial
cytoplasmic or inner membrane or the yeast plasma
membrane.
In addtion chlorhexidin has property of substantivity
(residual effect).
22. Concentration
0.2% is concentration commonly used for chemically plaque
control in oral cavity .
2% is concentration used as root canal irrigation.
23. Limitation
Unable to dissolve remaining necrotic tissue.
Less effective on gram negative than on gram positive.
Unable to remove smear layer.
24. Hydrogen Peroxide H2O2
It is a clear, colorless,odorless liquid.
H2O2 is active against viruses, bacteria,
and yeasts.
It has been particularly popular in
cleaning the pulp chamber from
blood and tissue remnants, but it has
also been used in canal irrigation.
26. Mechanism of action
It is highly unstable and easily decomposed by heat and
light.
it rapidly dissociate into H2O+O (water+nascent oxygen) .
the liberated O has bacteriocidal effect but this effect is
transient and diminishes in presence of organic debris .
The rapid release of O nascent oxygen on contact with
organic tissue results in effervesce (bubbling) action which
aid in mechanical debridement by dislodging dentin debris
and necrotic tissue particles and floating them to the
surface.
27. Concentration
It is recommended to use in 3%
conentration for endodontic
irrigation.
28. Advantages of using alternating 3% H2O2 with Naocl solution
are :
1.Effervescent reaction (bubbles pushes debris mechanichally
out of root canal)
2.Solvent action of sodium hypochrorite on organic debris.
3.Disinfection and bleaching effect by both solutions.
29. Limitation
Unable to remove smear layer.
Always use Naocl last because Hydrogen peroxide release of
nascent oxygen on contact with organic tissue which may
build up pressure on closing tooth and causes pain .
• Soft tissue emphysema may occur when hydrogen peroxide
irrigant enforced beyond the apical foramen.
30. MTAD
A mixture of tetracycline isomer, acid, and detergent.
(doxycycline, citric acid, and the detergent Tween-80)
32. Advantges
1) it is an effective solution for removal of most of smear
layer.
2) Antibactrial effect ( kill most significant bacterial strains i.e.
E faecalis which has been shown to resist to many
intracanal medicament and irrigants.).
3) It is biocompatible .
4) The high binding affinity of doxycycline present in MTAD for
dentin allows prolonged antibacterial effect. (substantivity)
33. Chelating Agents
EDTA (ethylene-diaminetetra-aceticacid)
The basic purpose of chelating
agent is lubrication ,emulsification
and holding debris in suspension .
34. Mechanism of action
• EDTA functions by forming calcium
chelate solution with calcium ions of
dentin which make it more friable and
thus dentin become easily to
manipulate by instrumentation.
35. EDTA
17% EDTA ( pH 7 )
EDTA has no antibacterial activity.
It effectively removes smear layer
by chelating the inorganic
component of the dentine.
Aid in mechanical canal shaping.
36. The optimal working time of EDTA is 15 minutes, after
which time no more chelating action can be expected.
37. Smear Layer
The smear layer is a layer of debris ,compromising both
organic and inorganic components, found on canal walls after
endodontic instrumentation, it is typically 1-2 um in thick .
It is made up largely of particularly dentin debris removed by
endodontic instrument during canal preparation but may also
contains remnants of pulp tissue and microorganisms.
38. Smear Layer
Presence of smear layer on the canal walls potentially
interfere with the adaptation of sealer against canal wall and
may create avenue of leakage of microorganisms by act as
substrate for microbial proliferation .
39. Smear layer removal
Can be accomplished by one of the following ways :
1) Use of chelating agents (17% EDTA) during the cleaning
and shaping . Upon complete the root canal shaping soak
the canal for 1 minute with liquid EDTA , then rinse the
canal thoroughly with NaOcl .
2) After irrigation with NaOcl Soak the canal for a 5 minutes
with MTAD as final irrigant.
Dry canal with paper points, so the it is now ready for
obturation .
42. ① Plastic syringe with needles
• Plastic syringes of different sizes
(1–20 mL) are most commonly used
for irrigation .
• All syringes for endodontic irrigation
must have a Luer-Lock design.
43. Types of endodntic needles
1) Beveled needle:
Needle with bevel if get lodged into
canal there is a risk of forcing
irrigant beyond the apex.
44. Types of endodntic needles :
2) Monoject irrigating needle:
Monoject endodontic needles to be
the most efficient delivery system in
which longer needles of a blunted,
open-end system were inserted to
the full length of the canal to ensure
optimum cleaning.
A larger volume of solution can be
delivered by this method.
45. 3) Max-i-Probe irrigating needle :
It has closed-end and side window.
This design allow for upward
flushing action for better canal
irrigation and also eliminates
possibilities of irrigant to be pushed
beyond the apical foramen.
46. Irrigation method:
It is strongly recommended that the needle lie
passively in the canal and not engage the walls.
A 27- or 30-gauge needle is preferred
The solution must be introduced slowly.
The irrigating needle should be bent to allow easier
delivery of the solution and to prevent deep
penetration of the needle.
Care must be taken with irrigants like sodium
hypochlorite to prevent accidents.
47. ② Gutta-percha Points
agitation
• use of apically fitting gutta-percha
cone in an up-and-down motion at
the working length. Although this
facilitates the exchange of the
apical solution, but the overall
volume of fresh solution in the
apical canal is likely to remain
small.
48. ③ EndoActivator
• It is based on sonic vibration
(up to 10,000 rpm) of a plastic tip
in the root canal. The system has 3
different sizes of tips that are
easily attached to the battery
operated handpiece that creates
the sonic vibrations.
49. ③ EndoActivator
• it allow more irrigant penetration
and mechanical cleansing
compared with needle irrigation,
with no increase in the risk of
irrigant extrusion through the
apex.
50. ④ Ultrasound
• Ultrasound is sound energy with frequency
above 25 KHZ.
• Passive ultrasonic irrigation have shown to
clean root canals or eliminate bacteria from
the walls better than conventional
methods.
51. Mechanism of action
• When a small file (size 10-20) is
placed freely in the center of the
canal following preparation and
ultrsonic activation is given . The
ulrtasonic energy passage through
irrigating solution and exerts its
(acoustic streaming effect ).
52. Mechanism of action
• This mechanichal energy warms the
irrigant solution (NaOcl) and dislodge
debris from canals.
• The combination of activation and
heating the irrigation solution is
adjunct in cleaning the root canal
system .
53.
54. ⑤ EndoVac
• The EndoVac system is based on
a negative-pressure approach whereby the
irrigant placed in the pulp chamber is
sucked down the root canal and back up
again through a thin needle with a special
design.
55. Advantges :
1) the EndoVac system lowers the risks
associated with irrigation close to the
apical foramen .
2) good apical cleaning at the 1-mm level
can be achieved by reversed flow of
irrigants and a strong antibacterial
effect when hypochlorite is used.
Irrigation is an important part of root canal treatment because it assists in remove bacteria and debris .
Ideal irrigant should have all or most of this positive properties.
Effective aginst microorganisms which are difficult to eradicate from root canals, such as Enterococcus, Actinomyces, and Candida organisms
Bystro¨m A, Sundqvist G. Bacteriologic evaluation of the effect of 0.5 percent sodium hypochlorite in endodontic therapy. Oral Surg Oral Med Oral Pathol 1983.
Chemomechanical reduction of the bacterial population in the root canal after instrumentation and irrigation with 1%, 2.5% and 5.25% NaOCL Siqueira Jr et al J Endod 2000.
One alternative approach to improve the effectiveness of hypochlorite irrigants in the root canal system could be to increase the temperature of low-concentration NaOCl solutions.
The unintentional injection of naocl into apical tissue due to wedging of irrigation needle or excessively high pressure in teeth with wide open foramen or root resorption .
Remain calm
becomes absorbed and gradually released from tooth structures such as dentin and cementum
Couse higer conc can be dangerous
The citric acid component in MTAD effectively removed a smear layer. Under these conditions, BioPure MTAD was more aggressive in eroding dentin than EDTA. In another investigation, however, the addition of NaOCl was necessary to achieve dissolution of organic matter.
For this reasons removal of smear layer piror to obturation is very important as it allow for better disinfection of root canal system and better adaptation of root canal sealer
Instrumented canal wall after removal of smear layer by naocl + EDTA
Traditionally, irrigation has been performed with a plastic syringe and an open-ended needle into the root canal space.
Allow for irrigant flow back.
The recognition of the difficulty of apical canal irrigation has led to various innovative techniques to facilitate the penetration of solutions in the canal. One of these includes the :Gutta-percha Points
Note It does not deliver new irrigant to the canal but it facilitates the penetration and renewal of the irrigant in the canal.
Ultrasonic proved superior to syringe irrigation alone when the canal narrowed to 0.3 mm (size 30 instrument) or less. (Teplitsky et al. 1987)