4. According to Webster’s dictionary
The term irrigation is defined as
- the therapeutic flushing of a body part with a stream of liquid
4
5. Why do we need irrigants???
Goals of root canal therapy
Eliminate infection
Which is done through
cleaning of organic remnants
shaping to receive a three dimensional filling of the
entire root canal space
Prevent re-infection
Obturation
Coronal restoration
5
6. The canal is
Cleansed primarily by irrigation
Shaped primarily by instrumentation
HENCE
CLEANING AND SHAPING
6
7. Failure of root canal treatment is likely caused by the
inability to eliminate bacteria from the root canal
system.
cleaning and shaping of the root canal system is able
to reduce the number of bacteria, however complete
disinfection of the canal is difficult
because of internal complexity of the root canal
system.
7
8. it has long been established that a root with “a
tapering canal and a single foremen” is the exception
rather than the rule.
Investigators have shown
multiple foramina,
additional canals,
fins, deltas, intercanal connections,
‘Cshaped’ canals and
accessory canals
which makes a root canal a far deviation from ‘a
tapared canal with a single foramen’
8
11. Thus a root canal irrigant is needed to aid in the
disinfection of the canals completely.
Studies have demonstrated that mechanical
instrumentation cannot sufficiently disinfect root
canals regardless of the instrumentation technique
or system used.
11
12. Despite technological advances in the ability to shape root canals,
at least 35% of root canal surfaces still remain uninstrumented
and Cleaning of the canal in terms of soft tissue removal and
elimination of bacteria Relies heavily on the adjunctive action of
chemically active irrigating solutions.
12
13. The choice of an irrigating solution for use in infected root
canals requires previous knowledge of the microorganism
responsible for the infectious process
as well as the properties of different irrigating solutions.
13
15. Potassium hypochlorite was the first chemically produced
aqueous chlorine Solution, invented in France by Bertholiet (1748-
1822).
First use of hypochlorite solutions was as bleaching agents.
Subsequently, sodium hypochlorite was recommended by
Labarraque(1777-1850) to be used for infectious diseases.
Based on the studies by Koch and Pasteur, hypochlorite then
gained wide acceptance as a disinfectant by the end of the 19th
century.
15
16. In world war II(1915),the chemist Henry Dakin and the surgeon
Alexis Carrel extended the use of a buffered 0.5% sodium
hypochlorite solution to the irrigation of infected wounds
It was observed that hypochlorite preparations are sporocidal,
virucidal , and show far greater tissue dissolving effects on
necrotic than on vital tissues
These features prompted the use of aqueous sod hypochlorite in
endodontics as the main irrigant as early as 1920
16
17. Prior to 1940’s Water(140-167 degree C) was the most commonly
used irrigant as it was readily available, inexpensive, provided a
lubricating effect during instrumentation.
During 1940's proteolytic enzymes like streptokinase, papain, etc
were used and they had tissue dissolving property.
17
18. Grossman and Meiman in 1941 introduced sodium
hypochlorite.
He recommended that solution of 3% hydrogen peroxide be
alternated with a solution of 5 .25% sodium hypochlorite, so
that effervescence action results in removal in debris from the
canal system.
In 1954, commercially available household bleach
(Chlorox,5.25% available chlorine) was first recommended by
Lewis.
18
19. In 1957 Nygaard Ostby introduced chelating agents(EDTA) as an
aid for preparation of narrow and calcified root canals.
Towards 1970's chelating agents were used increasingly because
of their biologically acceptable properties.
ln 1978 quarternary ammonium solutions was introduced as
irrigants by Spangberg.
19
20. ln 1979 Phosphoric acid, Citric acid and Lactic acid was used by
Wayman to remove smear layer from the root canals.
In 1980, Electrochemically activated water was used by
Russians as root canals irrigants.
In 1980 Martin and colleagues claimed that ultrasonics and
NaOCL act synergistically when used together for root canal
debridement.
20
21. In 1982 chlorhexidine was introduced by Delany for its use as an
irrigant emphasizing on its antibacterial properties.
Gly- oxide was used by Rome et al in 1985
The last few decades has seen the introduction of Ozone
Photodynamic therapy, Lasers as efficient tools for
intra canal disinfection.
21
23. Role of intracanal irrigants ( Weine)
loosens dentinal shavings and microorganisms from irregular
radicular dentine walls.
flushes - the above into the pulp chamber space where it is easily
removed by aspiration or paper points.
dissolves - Organic tissues that are entrapped in accessory or
lateral canals and that is inaccessible to hand instruments.
23
24. Role of intracanal irrigants ( Weine)
antimicrobial action - Certain irrigants posses germicidal
action, others reduce the number of microorganisms by
eliminating the source or substrate for survival of these
organisms.
lubricating effect-Facilitates instrumentation of the canals.
Some of the irrigants also possess a bleaching action.
24
25. goals of irrigation( Ingle)
Lavage of debris.
Tissue dissolution.
Antibacterial action.
Lubrication
25
26. Irrigants should possess low surface tension.
Low surface tension promotes flow of fluid into in accessible area.
high surface tension inhibit the spread of liquid over a surface to
limit its ability to penetrate a capillary tube.
26
27. The efficiency of an irrigant could be improved by reducing its
surface tension, thereby increasing its wettability hence-
penetration into the dentinal tubules of the main and lateral
canals.
Alcohol added to an irrigant decreases surface tension.
27
32. sodium hypochlorite
1. manufacture
2. mechanism of action
3. various actions- antimicrobial
-tissue dissolving property
-action on smear layer
-other actions
4. various concentrations
5. toxicity and complications
32
33. SODIUM HYPOCHLORITE
Most popular irrigating solution used as an irrigant for well over
many decades.
It was first recommended by Henry Dakin in 1915 and was called
as DAKIN‘s solution during the time of World War-ll
NaOCI 0.5% buffered with sodium biocarbonate was used for
treatment of infected wounds.
33
34. Commercially available household bleach (Chlorox – 5.25%
available chlorine) was first recommended by Lewis (1954), and
has since gained wide acceptance.
Other suggested brands include
Hypo (5% available chlorine),
Sainsbury’s household bleach (3% available chlorine)
34
36. ANTIMICROBIAL ACTION
NaOCl is best known for its antibacterial activity.
Studies have generally shown that NaOCl has a broad spectrum
antimicrobial activity -
It can rapidly kill vegetative bacteria, spore forming
bacteria, fungi, viruses, and bacterial spores.
Some investigations show the ability of even 0.5% NaOCl to kill
bacteria to a greater extent than other irrigants .
36
37. Mechanism of Action
Destruction of the bacteria takes place in two phases:
1. penetration into the bacterial cell.
2. chemical combination with the protoplasm of the bacterial cell
37
38. In water NaOCl disassociates into-
Na + OCl ions
HOCl
Between pH 4-7 chlorine exists predominantly as HCLO, whereas
above it as OCl
It is the hpyochlorous acid that is resposible for bacteria
inactivation.
38
39. The bactericidal ability of NaOCl results from the formation of
hypochlorous acid (HOCl), when in contact with organic debris.
which exerts its germicidal effect by oxidative action on
sulphydryl (-SH) groups of bacterial enzymes.
It disrupts oxidative phosphorylation and other membrane
associated activities as well as DNA synthesis.
As essential enzymes are inhibited, important metabolic reactions
are disrupted, resulting in the death of the bacterial cells.
39
41. Gomes et al. (2001) gave almost similar results regarding the time
taken to kill cultures of this species- E. faecalis
They have shown that
Percentages contact time
5.25% o.5 min
2.5 % 10 min
1.0 % 20 min
0.5% 30 min
41
42. Tissue solvent property
NaOCL posses strong tissue dissolution property.
The solvent action of NaOCI has been attributed to its high
alkalinity.
Grossman and Meiman reported that 5% sodium hypochlorite
dissolves pulp tissue in 20 min to 2 h.
42
44. Various concentrations
there has been much controversy over the appropriate
concentration of hypochlorite solutions to be used in
endodontics.
As Dakin's original 0.5% sodium hypochlorite solution was
designed to treat open (burnt) wounds,
it was surmised that in the confined area of a root canal system,
higher concentrations should be used , as they would be more
efficient than Dakin's solution .
44
45. Various concentrations
NaOCL has been used in various concentrations ranging from 0.5-
5.25%.
More recently upto 10% also.
the ADA (American Dental Association) accepted concentration
for clinical use of NaOCl as an irrigant is 5.25% (Cunningham et al.
1980).
Most commonly used concentration - 2.5%
The antibacterial effectiveness and tissue dissolving capacity of
NaOCl is a function of its concentration but so is its toxicity
45
46. The lower and higher concentrations are equally efficient in
reducing the number of bacteria in infected root canal
But the tissue dissolving effect is directly related to the
concentration
46
47. Baumgartner and Cuenin commented that-
The effectiveness of low concentrations of NaOCl may be improved
by using larger volumes of irrigant and replenishing fresh
solutions into the canal more frequently.
47
48. Effect of temperature
On pulp dissolution capacity
According to Waltimo, the capacity of a 1% NaOCl at 45°C to dissolve
human dental pulps was found to be equal to that of a 5-25% solution
at 20°C .
While at 60°C 1% solution was significantly more effective.
48
Clinically warming
NaOCl in a water bath
at 60ºC
50. Effect of temperature
On antimicrobial efficacy
The effects of temperature on sodium hypo short term stability,
pulp dissolution capacity and antimicrobial efficacy.
George Sirtes, Waltimo,Marc Schaetzle
Journal of endodontics sept 2005
A 100- fold increase in killing efficacy of E.feacalis was observed
between the corresponding NaOCl solutions at 20°C and 45°C in a
study conducted by George et al( 2005)
50
52. Effect of NaOCL on physical properties of dentin
Grigoratos et al. 2001, Sim et al.
International Endodontic Journal 2001.
A 2-h exposure of dentine to NaOCl solutions of more than 3%
significantly decreases the elastic modulus and flexural strength
of dentine compared to physiological saline
52
53. Corrosion of instruments
Corrosion adversely affects the metallic surfaces by causing pitting and porosity,
It is supposed that these microstructural defects can lead to areas of stress collection and crack
formation, weakening the structure of the instrument (Oshida et al. 1992).
and decreases the cutting effieciency of endodontic files (Stokes et al. 1999)
53
55. Corrosion of instruments
The corrosion rates of stainless-steel files in the tested solutions from
the highest to the lowest were:
0.2% chlorhexidine gluconate
> 5.25% NaOCl
>17% EDTA
55
57. A 1% concentration of NaOCl provides sufficient tissue
dissolution and antimicrobial effect,
but the concentration used has been as high as 5.25%
because of enhanced anti-microbial activity (Yesilsoy et
al. 1995).
As the concentration used rises so does its toxicity.
numerous reports have described clinical complications
because of the improper use of NaOCl
57
58. NaOCL toxicity
Sodium hypochlorite is a cytotoxic agent (Gatot et al. 1991,
Gernhardt et al. 2004).
When it comes into contact with vital tissue, it causes
haemolysis,
ulceration,
inhibits neutrophil migration
and damages endothelial and fibroblast cells (Gatot et
al.1991).
It has a pH of approximately 11–12 and causes injury primarily by
oxidation of proteins. (Kaufman & Keila 1989, Gatot et al. 1991,
Serper et al. 2004).
58
59. Damage to clothing
Probably the most common incidents during root canal
irrigation concern damage of the patients’ clothing.
Prevention
by proper protection of the patients’ clothing.
When using hand irrigation, one should assure that the
irrigation needle and syringe are securely attached.
59
60. Damage to the eye
Irrigant in contact with the patient’s or operator’s eyes
results in immediate pain, profuse watering, intense
burning, and erythema.
Management
Immediate ocular irrigation with large amounts of tap
water or sterile saline should be performed by the dentist
the patient should be referred to an ophthalmologist for
further examination and treatment (Ingram 1990).
60
61. Injection of sodium hypochlorite beyond the apical
foramen- NaOCL Accidents
when the apical constriction has been destroyed during
root canal preparation or by resorption.
may occur in teeth with wide apical foramina
Additionally,
extreme pressure during irrigation
or binding of the irrigation needle tip in the root canal
which results in contact of large volumes of the irrigant to
the apical tissues.
If this occurs, the excellent tissue-dissolving capability of
sodium hypochlorite will lead to tissue necrosis.
61
62. Symptomatology
Pain-
Immediate severe pain ( 2-6 minutes)
Oedema
Immediate oedema of neighbouring soft tissues
Possible extension of oedema over the injured half
side of the face, upper lip, infraorbital region
Bleeding
Profuse bleeding from the root canal
Profuse interstitial bleeding with haemorrhage of
the skin and mucosa (ecchymosis)
62
63. Symptomatology
Chlorine taste and irritation of the throat after
injection into the maxillary sinus may be experienced
by patient.
Secondary infection possible
Reversible anaesthesia or paraesthesia possible
63
66. 66
Swelling and extraoral ecchymosis
following inadvertent extrusion of
sodium hypochlorite (3%) through
the apical foramen of a maxillary
left cuspid.
67. Management
For the dentist-
remain calm
to inform patient on cause and severity of complication
Immediate irrigation with normal saline to dilute the NaOCl
inorder to reduce the soft tissue irritation.
Pain control
Immediate relief of acute pain- local anaesthesia nerve
block
analgesics- acetominophen.
In severe cases:
referral to a hospital
67
68. Antibiotics:
not obligatory. Only in cases of high risk or evidence of
secondary infection – amoxicillin 500mg
Antihistamine:
not obligatory
Corticosteroids:
Controversial- dexamethasone, methylprednisolone
For reduction of swelling
Extra oral cold compresses for the first 6 hrs
warm compresses and frequent warm mouthrinses to be
done after that.
68
69. Most patients recover within 1-2 weeks although some cases
of long term paresthesia and scarring have been reported.
Further endodontic therapy
with sterile saline or chlorhexidine as root canal
irrigants
69
70. Prevention of NaOCl accidents
The following steps can help clinicians avoid NaOCl accidents:
Adequate access preparation to facilitate better access.
Good working length control
Irrigation needle placed 1 mm to 3 mm short of working
length
The needle can be bent so as to confine the tip of it to higher
levels in the root canal.
Needle to be placed passively and not locked in the canal .
70
71. Irrigant to be expressed into the root canal slowly and
gently
"Flowback" of solution as it is expressed into the canal
should be observed
Constant in and out movements of the irrigating
needle into the canal space to be done to ensure that
the tip is free to express irrigant without resistance.
In case of any resistance felt irrigation to be
immediately stopped
71
72. Use of side delivery needles that are specifically de-
signed for endodontic purposes is advocated.
The hub of the needle should be checked for a tight fit
to prevent inadvertent separation and accidental
exposure of the irrigant to the patient’s eye.
72
73. Allergic reactions to NaOCl
The patient immediately will report of
severe pain and a burning sensation,
within a few s the upper lip and cheek up to the infraorbital
area may be swollen,
accompanied by ecchymosis and profuse haemmorhage from
the root canal.
Management
Systemic corticosteroid and antihistamine administered
intravenously and antibiotics are recommended.
73
74. NaOCL accidents
Palatal mucosa necrosis because of accidental sodium
hypochlorite injection instead of anaesthetic solution.
Gursoy UK, Bostancı V, Kosger HH.
International Endodontic Journal,2006.
74
75. Advantages
The ability of NaOCl to dissolve organic soft tissue of the
pulp
It is well recognized to be effective against a broad range of
pathogens: gram-positive and gram-negative bacteria, fungi,
spores, and viruses including the human immunodeficiency
virus.
Gross debridement and flushing out of debris.
Removes smear layer when used with EDTA.
75
76. Disadvantages
Acute inflammation followed by necrosis results when
NaOCl comes into contact with vital tissue- when extrude
out of the apical foramen.
Hypersensitivity, irritation to eyes
Corrosive nature on carbon steel instruments- if left within a
syringe may crystallize jamming the plunger.
May crystallize on the root canal walls
Effect on physical properties
Degraded by light, air, and contaminants- hence to use fresh
solution always.
76
77. Severe irritations have been reported when concentrated
solutions were inadvertently forced into the periapical region or
leakage through rubber dam
Furthermore a 5.25% solution significantly decreases the elastic
modulus and flexural strength of dentin
The reduction of intracanal microbiota is not any greater when
5% NaOCl is used as compared to 0.5%.
1% solution has shown to dissolve the entire pulp tissue during the
course of treatment when replenished frequently.
Hence based on the current evidences there is no rationale for
using hypochlorite solutions at concentrations above 1%.
77
80. H2O2 is a widely used biocide for disinfection and sterilization.
It is a clear, colorless liquid that is used in a variety of
concentrations in dentistry, ranging from 1% to 30%.
it degrades into water and oxygen.
H2O2 solutions are quite stable.
80
81. H2O2 is active against viruses, bacteria, yeasts, and even
bacterial spores .
The mechanism of action of this oxidizing solution involves the
reaction of superoxide ions to produce hydroxyl radicals, which
are the strongest oxidants known.
This radical can attack membrane lipids, DNA and other
essential cell components.
81
82. Moller recommended 30% H2O2 as the first step in tooth surface
disinfection.
It has been particularly popular in cleaning the pulp chamber
from blood and tissue remnants, it has also been used in canal
irrigation.
82
83. For years 3% H2O2 has been recommended as a canal irrigant
because of its effervescent action in presence of blood products.
effervescent action:
This action was specially indicated in mandibular teeth where the
bubbling of the peroxide was thought to lift debris from the canal
system.
However, H2O2 does not possess tissue dissolution properties
and is not effective as a lubricant.
83
84. Hence, alternate use of H202 + NaOCl irrigating solutions was
recommended by Grossman.
This alternate irrigation regimen during chemicomechanical
preparation produces-
1. Transient but energetic effervescence that mechanically forces out
debris and microorganisms out of the canal.
2. At the same time the 02 that is liberated in an active state assists
in destroying anaerobic microorganisms.
84
85. 3. ln combination with NaOCl it effectively removes the soft tissue
debris.
4. Increases the bleaching action on discolored teeth.
85
86. Certain disadvantages associated with it are-
It does not possess tissue dissolving property
Not a lubricant
Has limited antimicrobial action.
86
87. Complications
When peroxide is used it must eliminated from the pulp cavity
before the crown is sealed otherwise oxygen may be evolved
afterwards as a result of contact with blood or tissue fluids.
Besides causing pressure within the periapical region, this could
force debris and microorganisms into the tissues.
87
88. Complications
Injection of hydrogen peroxide beyond the apex:
Bhat (1974) reported a case in which hydrogen peroxide of
unknown concentration was injected into the soft tissues.
As treatment was performed under local anesthesia, the
patient experienced no pain but complained about a rapidly
developing swelling on the upper lip and some difficulty in
breathing.
The canal was left open, the patient was prescribed antibiotics
and instructed to apply cold packs.
The emphysema, caused by oxygen liberated from the hydrogen
peroxide, subsided in 1 week and root canal treatment was
completed. 88
90. Urea peroxide
(Endo-PTC or Gly-Oxide)
is another widely used solution to aid instrumenation
The peroxides are oxidizing agents that react chemically,
liberating great amounts of nascent oxygen that explains their
bactericidal action,
the effervescence, due to the liberation of oxygen,
contributes to the removal of pulp tissue remains and dentin
particles during the chemico-mechanical preparation.
90
91. Antimicrobial action-
Mechanism of action
Produces hydroxyl radicals that oxidixes sulphydryl groups, double
bonds in protiens, lipid and outer membranes- cause cell death.
It retains its antibacterial activity in the presence of blood whereas
aqueous 3% hydrogen peroxide does not.
91
92. The Urea Peroxide has several desirable characteristics for the
Irrigation of root canals
It presents detergent properties
not irritating to the periapical tissues and
non allergenic.
92
93. Glyoxide
is an irrigant comprising of 10% urea peroxide (carbamide
peroxide) in a vehicle of anhydrous glycerol .
93
95. Although NaOCl appears to be the most desirable single endodontic irrigant, it cannot dissolve
inorganic dentin particles and thus remove the smear layer formed during instrumentation.
In addition calcifications hindering mechanical preparation are frequently encountered in the canal
system which cannot be negotiated without use of chelating agents.
Demineralizing agents such as EDTA and citric acid have therefore been recommended as adjuvant in
root canal therapy
95
96. The term chelate originates from Greek word "chele" (crab claw)
Chelates are particularly stable complexes of metal ions with
organic substances .
The ability of chelator to bind and inactivate metallic ions is
widely exploited in medicine to bring about excretion of
dangerous ions in case of metal poisoning
or in treatment of copper metabolism disturbances.
96
97. Historical development of chelators
1957- Chelators were first introduced to Endodontics by Nygaard-
Ostby who recommended the use of 15% EDTA solution (pH 7.3)
Original Nygaard Ostby formula for 15% EDTA was:
-diSodium salt of EDTA - 17.0 g
-distilled water - 100.00 ml
-5N sodium hydroxide - 9.25 ml
97
98. Historical development of chelators
1963- A detergent was added to increase the cleaning and
bactericidal potential of EDTA.
The new composition being known as EDTAC which has 0.84g of
quaternary ammonium compound - Cetavlon
EDTAC reduced surface tension of the irrigant facilitating
wetting of the entire root canal wall thereby increasing the
ability of chelators to penetrate dentine.
It also had a greater anti-microbial effect than EDTA.
98
99. 1969- Strewart et al. introduced RC-Prep (Premier Dental) paste
type chelating agent.
Recently paste type chelators have regained popularity as
almost all manufacturers of Ni-Ti instruments recommend the use
of EDTA as a lubricant during rotary root canal preparation to
reduce the risk of instrument separation.
99
100. -Dimeralization action- dentin permeability
- working time
-Antibacterial action
-Biocompatibility
-Combined use of EDTA and NaOCl
-Other effects
-Various preparations
100
101. EDTA
ethylenediamine Tetra Acetic Acid (EDTA) is a chelating
substance that has been used as an irrigant.
It is capable of removing calcium ions of the dentin giving rise to
demineralization
and as a consequence, increasing the dentin permeability of the
root canals.
EDTA is used in concentrations from 10 to 17%
101
102. Demineralization
When EDTA solution comes in contact with dentine the calcium
ions are removed from dentine by the chelating action, causing
decalcification of dentine
EDTAH + Ca = EDTACa + H
as this reaction proceeds, acid accumulates and protonation
of EDTA prevails thus decreasing the rate of demineralization
EDTAH + H = EDTAH2
102
103. The extent of dimineralization zone is dependant on duration of
action( 20 min- 96 hrs)
A 20- 30 micron demineralized zone was apperent after 5 min.
This increased to 30- 40 µm after 30 min
And 50 µm after 24-48 hrs.
This layer was separated from the deeper unchanged dentin by a
clearly defined smooth demarcation line.
103
104. Self limiting action
This effect is found to be rapid during first 1 hr and reaches
equilibrium by the end of 7 hrs.
104
105. This demineralizing action
Removes inorganic component of smear layer
Reduces the time necessary for debridement
Aides in enlarging narrow/ obstructed canals
Helps bypass fragmented instruments
105
108. CHANGES IN DENTINE PERMEABILITY
after removal of smear layer with the aid of EDTA, dentin
permeability increased and reduction in micro leakage between
the definitive root canal filling and canal wall was achieved.
The ability of the sealer to penetrate the dentinal tubules and
thereby the adaptation of the root canal filling to the root canal
wall is much improved.
Further more this increase in root dentin permeability results in
an increase in the activity of endodontic medicament.
108
109. Working time of the chelator
Several studies have reported a good cleaning efficiency of EDTA
between working time of 1-5min.
Yamada et al. 1983,
Cergneux et al. 1987,
gait & Serper 2000,
Hulsmann & Heckendorff 2002,
Scelza et al. 2003.
109
110. Clinical recommendations
Hulsmann M, Heckendroff M, Lennon A.
chelating agents in root canal treatment: mode of action and
indications for use- a review
IEJ 2003
1) root canal preparation can be carried out with the aid of chelator
paste.
This may be introduced into the root canal with the preparation
instrument.
The canals first should have been flooded with NaOCl to dissolve
vital or necrotic tissue.
2) A chelator in paste form serves as a lubricant for files and
reduces the risk of instrument fracture in the canal.
110
111. 3. A final intensive rinse with 17% EDTA reduces the extent of the
smear layer remaining which in turn results in a cleaner canal
wall and better adaptation of the root fillings to the canal walls.
4. EDTA containing agents should be used between 1-5 minutes .
5. liquid EDTA solution may be introduced into the pulp chamber
to identify the entrance of calcified canals.
6. Apical extrusion of the chelator solution should be avoided.
111
112. Various preparations
liquid chelators:
Calcinase
Contains 17% Sodium edetate, sodium hydroxide as a stabilizer and
purified water.
REDTA (Roth International )
has 17% EDTA solution
with addition of 0.84g Cetrimide to reduce the surface tension.
112
113. EDTA-t
Contains 17% EDTA+ Sodium lauryl ether sulfate (Tergentol) as a
detergent.
EGTA (sigma)
main component is ethylene glycol bis ( amino ethyl ether)
N,N,N,N-tetra acetic acid.
It is reported to bind Ca+ more specifically than EDTA
Largal ultra (septodent)
contains 15% EDTA,
0.75% certimide
pH value to 7.4
113
114. Salvizol (Ravens,Germany)
N1-decamethylene-bis-4-aminoquinaldinium diacetate in
propylene glycol.
pH 6.6.
Kaufman et al. have suggested that salvizol with a neutral pH,
has a broad spectrum of bactericidal activity and the ability to
chelate calcium.
This gives the product a cleansing potency while being
biologically compatible.
114
115. Paste chelators
these paste chelators are the one most commonly recommended
with rotary instrumentation.
Calcinase slide:
it contains 15% sodium EDTA
58 to 60% water.
Has alkaline pH value of 8.9
it is water soluble hence easily rinsed from root canal system
The gel is firm at room temperature and develops a creamy
consistency when agitated .
115
116. RC-PREP-
It contains 15% EDTA,
10% Urea peroxide and
glycol in aqueous ointment base .
Oxygen is set free by reaction of NaOCI with RC-Prep resulting In
effervessence, so that pulpal remnants and blood coagulates can
be easily removed from the root canal wall (Stewart et al).
Glycol acts as a lubricant
116
117. Glyde file :
Is composed of 15% EDTA
10% Urea peroxide in aqueous solution.
It has got properties similar to RC-Prep .
FileCare EDTA
Also composed of 15% EDTA and
10% urea peroxide
file EZE
Contains 19% EDTA
117
118. Ruddle solution
contains:- 5% NaOCl,
Hypaque
17%EDTA
Hypaque is a high contrast radiopaque & injectable dye.
lt is water soluble with pH of 6.7- 7.7.
This composition simultaneously provides the solvent action of
full-strength NaOCl, visualization, & improved penetration.
Used to visualize the microanatomy, verify the shape, monitor
the remaining root wall thickness.
118
120. CITRIC ACID
One of its advantages is its non-cytotoxicity, it is more
acceptable biologically than other acids (Jenkin and Dawer 1963).
Many different concentrations of citric acid have been used, with
varying degrees of success.
10% , 20%, 25%, 50% solutions are used successfully for these
purposes .
A SEM study showed that 20% citric acid was slightly more
effective than 10% Citric acid; however, these differences did not
appear to be significant.
120
123. CHLORHEXIDINE
CHX in the form of a salt( gluconate, acetate or hydrochlorate)
has been widely used since 1950’s at different concentrations as
an oral antiseptic because of its excellent antimicrobial activity.
The most common preparation is with digluconate salt because
of higher water solubility.
pH of 5.5 – 7
of 5.5
123
124. CHLORHEXIDINE
Unlike NaOCl ,
CHX does not have a bad odor
Is not equally irritating to periapical tissues
Does not cause spot bleaching of patient and doctor’s clothes.
Has no deleterious effects on the physical properties of dentin
of 5.5
124
125. Structure
It is a cationic chlorophenyl bisguanide with bacteriostatic and
bacteriocidal action.
125
NH C NH C NH (CH2)6 NH C NH C
NH
NH NH NH NH
Cl Cl
126. Concentration
Include
0.12%,
0.2%,
and 2%
Commercially available oral rinse typically contains 0.12% CHX
gluconate.
0.12% CHX has been found to be ineffective for endodontic use
whereas concentrations above it have been successfully used
Sassone (2003)
Luciana M( Aust Endo J 2008)
Available in both gel and liquid formulations
126
127. Antibacterial action
It has a wide antimicrobial spectrum and is effective against both
Gram-positive and Gram-negative bacteria as well as yeasts,
while bacterial spores are resistant to CHX.
It shows comparatively greater efficacy towards gm positive
bacteria
It has been reported that CHX does not inactivate
lipopolysaccharide (LPS), which is a structural component of the
Gram-negative bacteria’s outer cell envelope
127
128. at physiologic pH CHX is a large dicationic molecule, with the
positive charge distrubuted over the nitrogen atoms on either
side of the heamatoxylin bridge.
The bacterial cell is characteristically negatively charged.
128
129. Low concentrations- bacteriostatic
High concentrations- bactericidal
CHX penetrates the cell wall and causes precipitation or
coagulation of cytoplasm probably caused by cross linking.
129
133. this results in micro leakage of intracellular
components leading to cell death
133
134. Substantivity
clinically CHX’s substantivity seems to be another advantage
over NaOCl, sustaining the antimicrobial activity over a period of
48 hours or 72 hrs after treatment
Their cationic properties also allow them to bind electrostatically
to surfaces
They are gradually released from the surface, as the
concentration of chlorhexidine in the environment decreases
TOOTH
134
135. The reversible reaction of uptake and release of CHX
results in a substantive antibacterial activity
Parsons et al 1980
Fardal and Turnbull 1986
Greesntein et al 1986
Jeansonne and White 1994
136. Biocompatibility
Extremely low level of tissue toxicity as compared to NaOCl ( as
low as 0.5%)
Loe 1973
Tanomaru Filho M IEJ 2002
Oncag O et al IEJ 2003
Allergic reaction to CHX are rare
Okano et al. 1989
Garvey et al 2001
136
137. limitation
The inability of CHX to dissolve organic matter
Jeansonne and White 1994
D’Arcangelo et al 1999
Marley et al 2001
Okino and Siqueira et al 2004
No action on smear layer
137
140. Bio pure MTAD ( Dentsply Tulsa Dental) is an irrigating solution
containing
An antibiotic- 3% doxycycline hydrate
An acid- 4.25% citric acid
A detergent- 0.5% polysorbate 80 (Tween 80)
140
141. Based on extensive well conducted studies MTAD has been shown
to be clinically effective,
Biocompatible
Removes smear layer while being less erosive
With potential sustained antibacterial activity.
141
142. dentinal erosion
142
Irrigating solution during root
canal preparation: 5.25% NaOCl.
Final solution for removal of smear
layer (5 min.): MTAD
Irrigating solution during root
canal preparation: 5.25% NaOCl.
Final solution for removal of smear
layer (5 min.): 17% EDTA
143. Tetraclean
Tetraclean is another combination product similar to MTAD
Similar to MTAD Tetraclean, is also capable of removing the
smear layer.
their low surface tension, increases the intimate contact of
irrigant solutions with the dentinal walls, they may permit
deeper penetration.
143
145. ECA
Russian scientists have developed a process whereby so-called
electro-chemically activated water (ECA) is produced with a new
and unique anode–cathode system (Leonov 1997).
ECA is produced from tap water and saline solution by a special
unit that houses a unique flow-through electrolytic module
(FEM).
to obtain the best end solutions with the ECA,
NaCI water solutions with no more than 5.0 g/L concentration
or fresh water of less than 1.0 g/L mineralization is needed.
145
146. The FEM contains the
Anode
-made from titanium and coated with
ruthenium-oxide, iridium and Platinum,
cathode
made from titanium coated with
pyrocarbon and glass carbon.
the anode being a solid cylinder fits
coaxially inside the cathode which is a
hollow cylinder
Membrane
Made up of ceramic in between them.
146
147. Electrolysis of water is known as a redox reaction.
At the anode,
electrons are removed from the water and it is oxidized, as in
2H202 = O2 + 4H+ 4e-
we get oxygen gas and hydrogen ions
At the cathode
electrons are added to the water as it is reduced,
2H2O + 4e = 2H2 + 4 OH
we get hydrogen gas and hydroxide ions.
147
148. The physical and chemical nature of ECA is not yet fully
understood.
The solution supposedly exists in a metastable or disequilibrious
state for 48 h after production and contains many free radicals
and a variety of molecules.
After 48 h the solution returns to the stable state, becoming
inactive again.
In the metastable state the solutions have a very high oxidation-
reduction potential.
Two types of ECA solutions are produced.
148
149. Oxidative potential water
Oxidative potential water (OPW) has been used extensively in
Japan for household and agricultural disinfection because of its
safety and bactericidal effectiveness.
According to the manufacturers’ claims, the antimicrobial and
antiviral activities of OPW are sufficiently powerful to kill a wide
variety of pathogens, including HIV.
The basis for the development of the OPW is that
microorganisms cannot survive in an aqueous environment with
both low pH (less than 3) and high oxidation-reduction potential
(greater than 0.9 V) (Becking et al . 1960).
149
150. Oxidative potential water is an electrochemically created, highly
acidic water that accumulates in the anode Compartment
OPW has strong antimicrobial activity, killing viruses as well as
bacteria, an unusually low pH of 2.7 or less, and oxidation-
reduction potentials of 1050 mV or greater
150
151. Oxidative potential water is well suited for dental treatment
because
of its low toxicity and lack of irritation to soft tissues,
and because it quickly loses its high oxidation-reduction
potential and low pH when it reacts with light-sensitive and/or
organic substances.
For these reasons it is completely safe as a root canal irrigant.
A study by Hata et al .( 1996) showed that OPW effectively
removed the smear layer from instrumented canal walls when
used as an irrigant.
151
152. 152
Middle third of a root canal irrigated with 10 mL.
(b) Apical third of a root canal irrigated
with 20 mL. Dentinal tubules were open,
although occasionally blocked by smear
plugs.
Middle and apical thirds of a root canal
irrigated with 30 mL.
Syringe irrigation with OPW removed
the superficial smear layer and debris
from the canal wall.
154. Ozone (O3) is an unstable gas, which breaks down into oxygen
very quickly
hence, it cannot be bottled, but must be generated fresh when it
is needed.
half-lifehalf-life - 40 minutes
154
155. MODE OF ACTION OF OZONE
when ozone dissolves in water, it becomes highly unstable and
rapidly decomposes through a complex series of chain reactions
(Hoigne & Bader 1976, Shin et al. 1999).
in two different and coexisting modes
one involving direct reactions of molecular ozone
the other a free radical-mediated reaction (Staehelin &
Hoigne´ 1985).
As a result, hydroxyl (OH) radicals are generated, which are
amongst the most reactive oxidizing species.
155
156. MODE OF ACTION OF OZONE
Both these mechanisms may be involved in the destruction of
bacteria by ozone.
Destroys microorganisms by oxidizing bacterial cell walls and
membranes and finally rupturing their membranes
156
157. OZONE THERAPY IN ENDODONTICS
The application of ozone makes the complete sterilization of the
root canal a real possibility in the near future.
Tooth that is to be treated ozonically needs to be built up so
that the clinical crown is restored.
Ozone is applied from the access opening, making the technical
realization a simple process.
There are five differently sized silicone cups
available to enable perfect tooth sealing
157
158. 158
Inserting the ozone cannula into the prepared
Root canal
Treatment with ozone with a complete seal
159. Ozone has limitations as it is irritating to the respiratory system
(Hazucha et al. 1989).
Very low concentrations (0.2–0.5 ppm) may cause headache, and
irritation or dryness of the nose, throat and eyes (McDonnell et
al. 1983).
Higher concentrations (1–10 ppm over a few hours) may cause
lung congestion, oedema, haemorrhage, changes to the blood
and loss of vital lung capacity.
It is irritating to the eyes and can cause redness, pain and blurred
vision
159
162. Lasers
The potential use of different endodontic lasers in eradicating
the root canal microbes has been the focus of interest for many
years.
dental lasers provide greater accessibility of formerly
unreachable parts of the tubular network due to their better
penetration into dentinal tissues
162
163. Lasers
Scientific research was first conducted with the Nd: YAG and the
diode lasers which gained widespread acceptance in the fields of
laser assisted endodontics,
For both wavelengths, a high disinfecting capability was
reported.
At the same time lasers suitable for the preparation of dental
hard substances like the Er:YAG and the Er.Cr :YSGG underwent
further development resulting in delivery systems also usable for
root canal application.
163
164. In various laser systems used in dentistry, the emitted energy can
be delivered into the root canal system by
a thin optical fiber
Nd:YAG
Er,Cr:YSGG
argon
diode.
or by a hollow tube –
C02
Er:YAG
Recent Investigations Indicate that these laser systems exhibit
satisfying bactericidal abilities thus constituting relatively new
additions to the spectrum of lasers used in endodontics .
164
165. It has been documented that
C02 ,
Nd:YAG,
argon,
Er,Cr:YSGG
and Er:YAG laser irradiation
has the ability to remove debris and smear layer from the root
canal walls following biomechanical instrumentation.
165
166. Limitations
There are several limitations that may be associated with the
intracanal use of lasers that cannot be overlooked.
The emission of laser energy from the tip of the optical fiber or
the laser guide is directed along the root canal and not necessary
laterally to the root canal wall.
Thus it is almost impossible to obtain uniform coverage of the
canal surface using a laser making complete removal of smear
layer and debris difficult
Investigators strongly recommended improving the endodontic
tip to enable irradiation of all areas of the root canal walls.
166
167. Limitation
Another limitation is the safety of such a procedure because
thermal damage to the periapical tissues potentially is possible.
Direct emission of laser irradiation form the tip of the optical
fiber In the vicinity of the apical foramen of a tooth may result In
transmission of the irradiation beyond the foramen.
Which in turn, may effect the supporting tissue of the tooth
adversely and can be hazardous in teeth with close proximity to
the mental foramen or to the mandibular nerve.
167
169. During the early 1990’s Prof. M. Wilson and Prof. G. Pearson first
proved PAD killed strep mutans in significant numbers and
reasoned that PAD could kill all bacteria involved in oral
infections in caries, root canals, and periodontics
Prof. Wilson and Prof. Pearson worked with Denfotex to convert
PAD into a routine clinical procedure, patented by both E.D.I.
and Denfotex.
169
170. Also known as photodynamic therapy(PDT)
is based on the concept that a nontoxic,photosensitizing agent
known as photosensitizer(PS) can be preferentially localized in
certain tissues and
subsequently activated by light of the appropriate wavelength to
generate
singlet oxygen and free radicals that are cytotoxic to cells of the
target tissues
170
171. Components
PAD solution
A dilute solution containing tolonium chloride which was
established as the most effective photosensitiser, packaged either
in syringes (for delivery to root canals) or dropper bottles.
SaveDent laser
A low power 635 nm laser light source which optimally activates
the solution.
171
172. APPLICATION
Canal is washed out thoroughly with sterile saline solution and
dried
P.A.D solution is introduced into canal from syringe via a
suitable needle and canal and pulp chamber filled with P.A.D
solution.
the solution is agitated in the canal for 60 s using an endodontic
file one size smaller than that to which the canal has been
prepared.
172
Root canal prepared PAD solution applied and agitated
173. The flexible emitter tip is introduced into
the canal until resistance
P.A.D laser is activated according to
manufacturer’s instructions for 150 s at 100 mW.
when the distance from the entrance in the pulp chamber to the
point of resistance in the canal exceeds 10 mm,
the canal is treated in sections by withdrawing the emitter in 5
mm steps and then irradiate each section for 150 s.
After canal has been completely treated, canal washed with
sterile solution and dried by aspiration followed by sterile paper
points.
173
174. How Does PAD Work ?
PAD solution is activated by 635nm light and acts as a
photosensitiser, releasing reactive oxygen species which disrupt
the membrane of the micro organism.
Independently, the laser and solution have no effect, but in
combination produce a powerful anti-bacterial action.
174
175. Bacteria before photo activated disinfection
Same bacteria sample after photo
activated disinfection process
showing disruption of membrane.
175
176. Mixed lactobacilli and streptococci bacteria in
an infection
PAD solution (in blue) attached to
bacteria
PAD solution activated by
red laser light
Bacteria destroyed by PAD
176
177. Efficacy
Extensive laboratory and in-vitro studies at the Eastman Dental
Institute, London, together with clinical assessment in Germany
and UK in root canals and carious lesions have clearly proved the
efficacy of PAD.
PAD has been shown to kill all types of bacteria commonly found
in caries and root canals including-
Streptococcus mutans, S. sobrinus, S. intermedius
Actinomyces
Lactobacillus
Veilonella
Prevotella intermedia
Peptostreptococcus micros
Fusobacterium nucleatum
E. faecalis
177
179. An alternative regimen for root canal disinfection
Bonsor, R. Nichol, T. M. S. Reid and G. J. Pearson
Br Dent J 2006
Results of this study indicate that the use of a chelating agent
and photo-activated disinfection to kill bacteria is an effective
alternative to the use of hypochlorite as a root canal cleaning
system.
Soukes et al JOE 2006 showed the combination of methylene blue
with red light were able to eliminate 97% of E.feacalis biofilm
bacteria in root canals .
179
180. PAD
Seal GJ, Gulabivala K.IEJ 2002
The combined use of a photosensitizing agent and a low power
laser directed at the access cavity was bactericidal to S.
intermedius biofilms in root canals but was unable to achieve
total kill, unlike 3% NaOCl.
180
181. ADVANTAGES
PAD can be applied effectively for killing gram-positive, gram-
negative, aerobic and anaerobic bacteria - in fact, all commonly
encountered bacteria associated with dental disease.
PAD can kill bacteria in complex biofilms, which are typically
resistant to the action of antimicrobial agents.
Photo activated disinfection overcomes the problems of
antibiotic resistance.
PAD does not pose any thermal risks due to the low power of the
PAD laser.
181
182. Disadvantages
At the concentration provided, PAD solution produces no side
effect other than
a transient color change in the dentine on the surface of the
canal wall.
This is removed by the washing process with sterile saline
performed after disinfection of the canal
182
183. QMiX (QUÍMICO MECÁNICA MIX)
Q mix is an irrigation solution used as a final rinse. It is
a combination of CHX with EDTA and a surfactant
solution to improve penetration in dentinal tubules.
Advantages:
Low surface tension is one of the ideal characteristics of an irrigant
Superior Antibacterial efficacy.
Superior smear layer removal
Ready to use, fast working
Less demineralization OF DENTIN compared to EDTA
6% NaOCl and QMiX were the most effective disinfecting solutions
against the young biofilm, whereas against the 3-week-old biofilm, 6%
NaOCl was the most effective followed by QMiX
186. Herbal
• Murray et al. evaluated Morinda citrifolia juice in conjunction with
EDTA as a possible alternative to NaOCl.
• Triphala (IMPCOPS Ltd, Chennai, India) is an Indian ayurvedic herbal
formulation consisting of dried and powdered fruits of three
medicinal plants, Terminalia bellerica, Terminalia chebula, and
Emblica officinalis, and green tea polyphenols (GTPs; Essence and
Flavours, Mysore, India); the traditional drink of Japan and China is
prepared from the young shoots of tea plant Camellia sinensis.
• Dimethyl sulfoxide (DMSO) is used as a solvent for Triphala and GTP,
although they are readily soluble in water. DMSO is a clean, safe,
highly polar, aprotic solvent that helps in bringing out the pure
properties of all the components of the herb being dissolved
186
187. • Herbal alternatives showed promising antibacterial efficacy on 3- and
6-week biofilm along with MTAD and 5% sodium hypochlorite.
• Although Triphala and green tea polyphenols (GTPs) exhibited similar
antibacterial sensitivity on E. faecalis planktonic cells, Triphala
showed more potency on E. faecalis biofilm. This may be attributed
to its formulation, which contains three different medicinal plants in
equal proportions. In such formulations, different compounds may
be of help in enhancing the potency of the active compounds
resulting in an additive or synergistic positive effect.
• According to Prabhakar et al. 5% of sodium hypochlorite exhibited
excellent antibacterial activity in both 3-week and 6-week biofilm,
whereas Triphala and MTAD showed complete eradication only in 3-
week biofilm
187
188. • Triphala and GTPs are proven to be safe, containing active
constituents that have beneficial physiologic effect apart from its
curative property such as antioxidant, anti-inflammatory, and radical
scavenging activity and may have an added advantage over the
traditional root canal irrigants.
188
190. Although the technique for irrigation is simple, the potential for
serious complications exists.
Regardless of the delivery system,
-the solution must be introduced slowly
- the needle never wedged in the canal
As a rule, the clinician should irrigate copiously, recapitulate and
continue.
190
191. The most common method of delivering irrigant into the canal is
with the aid of a syringe and needle
A 5 ml syringe with a Leur Lok mechanism is the preferred one.
Gauge of the needle
Gauges ranging from standard 22 to finer 30 have been used in
endodontic irrigation.
Since irrigation of the apical third requires the needle to be in
close proximity for adequate effect the canals should be flushed
with a 27-30 gauge preferably.
191
192. For relatively large canals the tip of the syringe is placed until
resistance from the canal wall is felt, the tip is withdrawn a few
millimeters, the solution is expressed very slowly until the
chamber is full.
In treatment of posterior teeth and or small canals the solution
is deposited in the chamber .
The file will carry the irrigants into the canals and the capillary
action of narrow canal diameter will retain much of the solution.
192
193. Excess irrigant is carried away by aspiration with a small tip of
approximately 16 gauge otherwise a folded gauze pad is held near
the tooth to absorb the excess.
Several types of plastic disposable syringes are available.
193
194. It should be bent approximately 30degrees in the center of the
needle to allow easier delivery of the solution and to prevent deep
penetration of the needle or probe.
194
195. 195
Squeezing the plunger with the thumb
may result in more rapid delivery
Of irrigant and possible extrusion
Using a forefinger to depress the plunger
gives greater control of irrigant delivery
196. Designs of needle
1. open ended blunt needles
2. beveled needles
3. blunt ended side venting needle
4.notched tip
5. perforated needle
196
198. Designs of needle
ProRinse probes
The effectiveness of the ProRinse seemed related to its design.
It has a blunt tip, with the lumen 2 mm from the tip.
Expression of fluid through the lumen creates turbulence around
and beyond the end of the probe.
Also prevents forceful periapical injection of irrigant.
198
200. Moser and Heuer reported 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.
200
201. Stropko NI-TI irrigation needles
They are available in short (17 mm) and (25 mm) long sizes and
can be sterilized and reused.
Needle size is 27 gauge, side vented.
Advantages are its good flexibility and their resistance to
clogging.
201
202. MAX-l-PROBE
These are designed to produces upward flushing motion for
complete canal irrigation.
Side port dispersal prevents solution and debris from being
expressed through the apex closed,
rounded end reduces risk of apex damage.
Closed-end needle eliminates possibilities of puncture of the
apical foramen
202
204. THE ENDO VAC SYSTEM
The EndoVac system (Discus Dental) consists of a
delivery/evacuation tip attached to a syringe of irrigant and the
highspeed suction of the dental unit.
A small tube attaches either a macro or micro-cannula to the
suction.
The delivery/evacuation tip places irrigant in the chamber and
siphons off the excess to prevent overflow.
204
205. THE ENDO VAC SYSTEM
The macro-cannula is plastic with an open end that measures
size 55 with a 0.02 taper.
The micro-cannula is stainless steel and has 12 small, laterally
positioned, offset holes in 4 rows of 3, with a closed end
measuring ISO size 30.
The micro-cannula can be used at working length in a canal
enlarged to ISO size 35 or larger.
205
206. 206
Scanning electron microscope photograph of
the microcannula
Comparison picture of
the closed-ended
microcannula
(ISO size 30)
open-ended macrocannula
(ISO size 55).
207. 207
The macrocannula attached to its handle used for
initial flushing of the coronal portion of the canal.
The microcannula attached to its handle.
and is used for irrigation at the apical portion
of the canal to working length.
208. 208
The delivery/evacuation tip attached to a syringe.
Irrigant is delivered to the pulp chamber by the metal needle.
Any excess is immediately suctioned off through the plastic tubing
surrounding the metal that is attached to the suction.
209. 209
A) The complete EndoVac system including all tubing and vacuum
attachment.
The free end of the large tubing plugs into the high speed
suction of the dental chair.
210. MICRO BRUSHUS
Advancement in small wire technology, bristle materials and
bristle attaching techniques have enabled the creation of an
endodontic microbrush of clinical field testing.
A micro-brush is provided to remove the smear layer that
remains in the root canal after the pulp, bacteria, and related
irritants have been mechanically and chemically removed from
the root canal using files and irrigants like sodium hypochlorite.
210
211. The brush includes a shaft or shank and a tapered brush section
extending from the distal end of the shank.
The brush section includes bristles extending radially from a
central wire base.
The shank can be provided with a handle for manual use or the
shank can be adapted to be received in a rotary, sonic, or
ultrasonic handpiece to impart rotational or vibratory motion to
the micro-brush.
211
212. The brush section has a diameter of between about 0.2 mm and
about 0.7 mm at a tip end and a diameter of between about 1 mm
and 2 mm at a coronal-most end.
The brush section is about 16 mm long, and thus has a taper of
about 0.06 mm/mm and about 0.12 mm/mm.
212
213. Rotary and ultrasonic endo brushes are fabricated in ISO
lengths, containing 16mm of bristles, have the bristle diameter of
0.40,0.50,0.60 and 0.80mm
Rotary activated microbrushes run at about 300 rpm and the
helical bristle pattern effectively augers residual debris out of the
canal in coronal direction
Microbrushes designed for ultrasonic use effectively brush the
walls of the preparation and activate solution of NaOCl and 17%
EDTA to produce cleaned canal.
213
216. Ultrasonic irrigation
Ultrasonic devices were first introduced in Endodontics by
Richman (1957).
Martin and Cunningham have coined the term endosonics.
In 1976 Martin had designed the first commercial system which
used ultrasonics for preparing root canal.
216
217. Ultrasonic irrigation
Ultrasonically activated files have the potential to prepare and
debride root canals mechanically.
The files are driven to oscillate at ultrasonic frequencies of 25–30
kHz
The files operate in a transverse vibration, setting up a
characteristic pattern of nodes and anti-nodes along their length
(Walmsley 1987, Walmsley & Williams 1989).
Ultrasonic irrigation has been shown not very effective for
shaping the root canal.
217
218. On the other hand it has been shown that ultrasonically driven
files are effective for the ‘irrigation’ of root canals.
Two types of ultrasonic irrigation have been described in the
literature:
1. where irrigation is combined with simultaneous ultrasonic
instrumentation (UI)
2. without simultaneous instrumentation, so called passive
ultrasonic irrigation (PUI).
218
219. Acoustic streaming
Acoustic streaming is the rapid movement of fluid in a circular or
vortex-like motion around a vibrating object. ( file)
The acoustic streaming that occurs in the root canal during
ultrasonic irrigation has been described as acoustic micro-
streaming.
The shear flow caused by acoustic microstreaming produces
shear stresses along the root canal wall, which can remove debris
and bacteria from the wall.
219
221. Cavitation
Acoustic cavitation can be defined as the creation of new bubbles
or the expansion, contraction and/or distortion of pre-existing
bubbles (so-called nuclei) in a liquid, the process being coupled to
acoustic energy (Leighton 1994).
These bubbles expand and then rapidly collapse producing a
focus of energy.
221
223. 223
Dentine debris packed in oval shaped
root canal after syringe irrigation
and clean oval canal after 3 min
of PUI
224. 224
SEM micrograph of a size 15 stainless
steel K-file used for ultrasonic
activation of the irrigation
SEM micrograph of a blunt
Ni–Ti-wire used for
ultrasonic activation of the
irrigation
225. Application of irrigant during PUI
Two flushing methods can be used during PUI, namely
a continuous flush of irrigant from the ultrasonic handpiece
or an intermittent flush method using syringe delivery
(Cameron 1988).
In the intermittent flush method, the irrigant is injected into the
root canal by a syringe, and replenished several times after each
ultrasonic activation.
Both flushing methods were equally effective in removing dentine
debris from the root canal in an ex vivo model when the
irrigation time was set at 3 min (van der Sluis et al. 2006).
225
226. Heat generation
Cameron (1988) reported a rise of the intracanal temperature
from 37 to 45 C close to the tip of the instrument
and 37 C away from the tip when the irrigant was ultrasonically
activated for 30 s without replenishment.
The external root surface temperature recorded was 40 C
A cooling effect from 37 to 29 C was recorded when the irrigant
was replenished with a continuous flow of irrigant.
Ahmad (1990) reported a mean rise of temperature of 0.6 C during
a continuous flow of irrigant.
A rise of temperature within these ranges will not cause
pathological temperature rises in the periodontal ligament.
226
227. Based on this literature review it is concluded that PUI appears to
be an adjunctive treatment for cleaning the root canal system
and that PUI is more effective than syringe irrigation.
227
228. THE MICROMEGA 1500
is a sonic hand pieces that can be used with endodontic files and
irrigation solutions to debride canals.
Sonic handpieces allows for simultaneous canal flaring,
debridement and irrigation with cavitation effect.
228
229. Endo Irrigator Plus (K Dent Dental System)
It is based on ACWIS concept, i.e. activated continuous warm
irrigation and evacuation system.
Strong vacuum evacuation system insures that Sodium Hypochlorite
doesn’t reach the periapical region so it does not harm or damage the
peri-apical tissues.
This device creates positive and negative pressure inside the canal.
This gives a perfect cleaning and disinfection of root canal assisted by
negative and positive pressure with warm Sodium hypochlorite.
In this unit the Sodium hypochlorite is warmed upto 45°. Positive
pressure irrigation with warm hypochlorite cleans and disinfect upto
middle 1/3rd, removes all macro debris and negative pressure
irrigation with warm hypochlorite cleans and disinfect upto apical
1/3rd, removes all micro and nano debris.
According to the manufacturers due to its powerful suction ability not
even a single drop of Sodium Hypochlorite solution comes out of the
canal (even if working in maxillary molars or if there is wide/ open
apex) 229
232. Conclusion
Instrumentation of the root canal system must always be
supported by an irrigation system capable of removing pulp
tissue remnants and dentin debris.
Liberal amounts of irrigation are essential for the effective
function of the files.
A variety of chemical agents in fluid form and sometimes in
viscous preparation has been used to aid canal preparation and
irrigation.
232
233. Conclusion
The most popular and advocated irrigation is sodium
hypochlorite in various concentration.
Ongoing researchers are directed towards comparing the
different irrigating solutions and different methods of irrigation
to enhance the cleanliness of the root canal preparation
Clinician must always be alert to fundamental concept of
cleaning and shaping that provide success of root canal
treatment.
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234. Many new materials and methods have recently been introduced
to improve root canal debridement and to achieve root canal
sterilization.
However, bearing in mind the complex anatomy of the root canal
system and the ability of microorganisms to survive under
adverse conditions, it might be premature to believe that the
total sterilization of the root canal system could be readily
achieved by any of the systems.
In the age of evidence-based dentistry, it is advisable to wait until
quality independent data are available to support the use of such
new technologies.
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