In vital teeth, pulp chamber and root canals may contain vital tissue and in case of non vital teeth, the pulp canal will contain necrotic pulp remnants and tissue fluid. In some cases bacterial byproducts and bacteria may also be present inside the root canal.
Careful removal of these pulpal contents is necessary for successful root canal treatment without pushing the contents into the periradicular spaces.
When irrigation is done during canal instrumentation, irrigant loosens the debris, pulp tissue and microorganism from the dentinal walls allowing them to be easily removed from the canal.
While cleaning the root canal, Preliminary debridement is accomplished by hand instr-uments, but pulp remnants are not completely removed. So, chemical dissolution of the remaining tissue is necessary.
Irregularities from the root canal system such as accessory canals, lateral canals, apical deltas and narrow isthmus prevent complete removal of root canal contents by mechanical debri-dement alone. In these areas bacteria can strive and residual tissue tags provides pabulum on which the bacteria can survive.
Irrigation serves as a mechanical flush to remove the debris as well as serving as a bacterial agent and also as tissue solvent in some cases.
Host defense is responsible for the prevention of spreading canal infections to the bone and to other parts of the body. The body defense is usually successful in stabilizing the lesion size and preventing its expansion after the initial growth period. However, because of the lack of circulation, host defense mechanisms cannot effectively reach the microbes residing inside the tooth in the necrotic root canal system. Mechanical instrumentation removes a portion of the microbes from the main root canal space, but its main purpose is to enhance irrigation and the placement of medication and the root filling. Irrigation supports mechanical instrumentation, by reducing friction and removing dead and living microbes from the root canal. In addition, many irrigating solutions have antimicrobial activity that effectivelykill residual microbes in the canal. Intracanal antimicrobial medicaments, on the other hand, are used in multi-appointment endodontic treatments to complete the work started by instrumentation and irrigation and, optimally, to render the root canal system bacteria-free.
When NaOCl is added to water, hypochlorous acid is formed, which contains active chlorine, a strong oxidizing agent. Available evidence suggests that chlorine exerts its antibacterial effect by the irreversible oxidation of sulfhydryl groups of essential enzymes, disrupting the metabolic functions of the bacterial cell. It is well known that an increase in NaOCl concentration in a solution brings a corresponding increase in the antibacterial activity as long as other factors such as pH, temperature, and organic content are held constant.
A commercially available oral rinse contains 0.12% chlorhexidine gluconate in base containing water, 11.6% alcohol, glycerine, flavoring age-nts, and saccharin. Approx-ima-tely 30% of Chlorhexidine is reta-ined in the oral cavity after rin-sing and is slowly released into the oral fluids. This substantive antimicrobial activity has been identified as a potentially prot-ective element in the canal tissues for many hours after instru-mentation.
At low concentrations of 0.005-0.01 %, a stable monolayer of chlorhexidine is observed, which might change the phy-sical and chemical properties of the tooth surface and prevent or reduce bacterial colonization. At higher concentrations, multilayers of chlorhexidine are present and the excess of chlorhexidine can be released rapidly into the surro-unding environment. This reve-rsible reaction of uptake and release of chlorhexidine results in a substantive antibacterial activity usually referred to as "subs-tantivity".
Advantage of chlorhexidine gluconate over sodium hypo-chlorite is that, even through both are effective as anti-microbial agents; chlorh-exidine gluconate is relatively nontoxic. Another advantage of using chlorhexidine is that it could be used in patients those are allergic to sodium hypo-chlorite and teeth with open apices. The major disad-vantage of using chlorhexidine glu-conate as the primary endo-dontic irrigant is that it lacks the ability to dissolve necrotic pulp tissue.
Studies have sugg-ested that distilled water or pure water should be used as an irrigant to eliminate H2O2 in the canal. Usually, NaOCl is used as the final irrigant in root canal irrigation. Because of possibility of development of pressure due to O2 liberation, H2O2 must always be neutralized by NaOCl and not be sealed in the canal. NaOCl reacts with H2O2 and liberates the remaining oxygen and then the canal can be dried with a paper point so that if there is any remaining irrigant, it is absorbed.
It can decalcify up to a 50-mm thin layer of the root canal. EDTA is normally used in concentration of 17%. It removes smear layers in less than 1 minute if the fluid is able to reach the root canal wall surface. Goldberg and Spielberg have shown that the optimal working time of EDTA is 15 minutes, after which no more chelating action can be expected. The decalcifying process is self-limiting, because the chelator is used up. To achieve continuous effect the EDTA must be replaced through frequent irrigation. EDTA reacts with glass, so syringes of glass material should not be used. For root canal preparation, EDTA has limited value as an irrigation fluid.
Zubriggen et al., however, reported that a residue of RC-Prep remains in the canals in spite of further irrigation and cleansing. This led to the question of the effect of RC-Prep residue on apical seal. Cooke et al. showed that RC-Prep allowed maximum leakage into filled canals over 2.6 times the leakage of the controls.
A new irrigation solution (MTAD), containing a mixture of a tetracycline isomer (doxycy-cline, Sigma-Aldrich Company, St Louis, MO), an acid (Citric acid, Sigma-Aldrich), and a deter-gent (Tweem-80, Sigma-Aldrich) on the surface of instrumented root canals has been developed
Various chemicals have been used to remove the smear layer. They include different formulations of EDTA, acetic acid, citric acid; polyacrylic acid, tannic acid, and Bisdequa-liniumacetate. Results showed that none of the above solutions were as effective as 5 ml of a mixture of doxycycline and citric acid for 1 to 5 min in removal of the smear layer.
It is the most common and conventional set of irrigation techniques.It involves dispensing of an irrigant into a canal through needles/cannulae of variable gauges, either passively or with agitation by moving the needle up and down the canal space without binding it on the canal walls. The needle/cannula should remain loose inside the canal so that it allows the irrigant to reflux and causes more debris to be displaced coronally, while avoiding the extrusion of the irrigant into periapical tissues. Some of these needles are designed to dispense an irrigant through their most distal ends, whereas others are designed to deliver an irrigant laterally through closed-ended, side-vented channels. The latter design has been proposed to improve the hydrodynamic activation of an irrigant and reduce the chance of apical extrusion. Advantage of syringe irrigation is that it allows good control of needle depth and the volume of irrigant that is flushed through the canal.Disadvantage is that it is Difficult to standardize fluid flow rate. Inaccessible canal extensions likely to harbor debris and bacteria. Mechanical flushing action created by conventional hand-held syringe needle irrigation is relatively weak.
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. Drying should be done with absorbent points.
Grossman recognized the need for adequate enlargement of the root canal to improve irrigation efficacy in 1943.
It has been reported that hand-held syringe needle irrigation is less effective when the canal is enlarged to less than size 40 at the apex. Therefore, clinicians need to balance the mechanical efficacy of irrigation via canal enlargement. This leads to inadvertent reduction in radicular dentin thickness and subsequent weakening of the root structure.
“Today it’s our turn”
DR SNEHA RATNANI
The ideal requirements of irrigation
1. It should have broad spectrum of antimicrobial activity.
2. It must aid in debridement of the canal system.
3. It should have the ability to dissolve necrotic tissue.
4. It should have low toxicity level.
5. It should be a good lubricant.
6. It should have low surface tension so that it can easily flow into inaccessible
7. It should be able to effectively sterilize the root canal.
8. It should be able to prevent formation of smear layer during instrumentation
or remove the latter once it has formed.
9. It should inactivate microbial toxins.
10.It should not corrode instruments.
11. Dissolve inorganic tissue.
12.Penetrate to canal periphery.
13.Do not weaken tooth structure.
Lavage Of Debris
Quantity and temperature
Time of contact
Type and gauge of irrigating needle
Gulabivala k et al 2005
One of the early irrigating solutions used for
flushing of the root canals showed good
Studies performed in 1955 by Lorixzy et al
showed periapical bone regeneration of after
mechanical instrumentation using tap water
as an irrigating solution.
A stream of hot water, 140-178°F discharged
from an insulated syringe was the first
From a biological stand point, sterile normal
saline is the best irrigant to use because it causes.
• Least apical tissue irritation or damage.
• Least amount of cell lysis.
• However saline solution does not remove the
smear layer but merely flushes out some of the
superficial debris from the root canal system.
• Has poor antibacterial properties,
• It should not be used alone as root canal irrigant, it should be used as
an adjunct to the chemical disinfectant where the chemical irrigant
provides disinfection and the dissolution properties and saline helps in
• It can also be used as a final flush of the root canal to remove any
chemical irrigant left inside the root canal.
• White, odorless, crystalline powder.
• In 1951, Blechman and Cohen suggested 30% urea solution can be used as
• Mild solvent for necrotic tissue, pus and an antiseptic too.
Mechanism of action
• Denaturation of proteins by destroying bonds of secondary structure
resulting in loss of functional activity of proteins.
• Chemically debrides the wound by softening underlying substrate of fibrin.
• White crystalline powder with slight odor, soluble in water, alcohol and
• Dissociates into urea and hydrogen peroxide
• 10% urea peroxide solution with anhydrous glycerol available as glyoxide
• Glycerol increases stability of urea peroxide solution, increases its shelf life, acts
as a good lubricant facilitates negotiation of fine tortuous canals.
• It dissociates very slowly.
• Its effervescence effect is prolonged
but not pronounced.
• This can be overcome by
alternating irrigation with hypochlorite.
The use of sodium hypochlorite for treating wounds
was introduced during World War I by a physician
named Dakin The solution used is called Dakin’s
solution and is used for lavaging large flesh
• Sodium hypochlorite is a reducing agent.
• It is a clear, straw coloured solution containing
about 5% of available chlorine.
• The solution should be kept in a cool place away
• Popular household bleaching agents such as Clorox
or purex are usually 5.2% solution of sodium
hypochlorite and are satisfactory.
• Solution ranging in strength from 0.5 to 5.25% have been recommended
for use in endodontics.
• NaOCl should be used clinically in concentration of 2.6 – 5.25% to take
advantage of its ability to dissolve pulp tissue from all aspects of the root
• Increasing concentration will increase the rate at which organic material is
dissolved and may improve its effectiveness as an antibacterial agent.
• 50% dilution of commercial preparation (clorox) with distilled water gives
a solution of 2.6% NaOCl.
• Sodium hypochlorite (Naocl) has a broad-spectrum antimicrobial activity. It
can rapidly kill vegetative bacteria, spore-forming bacteria, fungi, protozoa,
and viruses (including HIV, rotavirus, HSV-l and -2, and hepatitis A and B.
• Heating the solution elevating the temperature causes an increase in the tissue
solvent action of the NaOCl. Too high a temperature can cause breakdown of
• Clinically a 60o C warm water bath is prepared by placing a beaker of water on
a hot plate. Preloaded syringes of NaOCl maybe warmed by placing them into
this warm water bath.
• The Endo Irrigator II has 3 reservoirs for irrigating solutions NaOCl
5.25 %, EDTA 17% and alcohol 95%. The gun on the right has four
buttons. Three to activate the solutions and one is for suction. The gun
on the right is a Stropko irrigator and is an option. The device has a
built in heater that also heats the lines so the irrigating solutions come
out warm. There are two settings that allow for "push-intermittent"
and push-on, push-off" dispensing of the solutions.
• Solutions of NaOCl should be prepared fresh daily to obtain optimal clinical
• Stable shelf life of 5.25% NaOCl – 10 weeks.
• Whereas 2.6 and 1.0% NaOCl - 1 week after mixing with water.
• Disinfection by means of NaOCl is initially slow, but increases progressively.
• In fact one of the most advantages of pretreatment is to build teeth up so they
have pulp chambers that can retain irrigants.
• The potential for an irrigant is maximized when it is heated, flooded into shaped
canals and given ample time to work.
• Mechanism of Action of Sodium Hypochlorite
• - Direct contact with microorganisms.
• - Vapor 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 that
Sodium hypochlorite acts as an organic and fat solvent degrading fatty
acids, transforming them into fatty acid salts (soap) and glycerol
(alcohol), -> reduces the surface tension.
• Sodium hypochlorite neutralizes amino acids forming water and salt
• With the exit of hydroxyl ions, there is reduction of pH.
• Results in formation of Hypochlorous acid, when in contact with organic tissue
acts as a solvent.
• It also releases chlorine that, combined with the protein amino group, forms
• Hypochlorous acid and hypochlorite ions (OCl - ) lead to amino acid
degradation and hydrolysis.
• The chloramination reaction between chlorine and the amino group (NH)
forms chloramines that interfere in cell metabolism.
• Chlorine (strong oxidant) presents antimicrobial action inhibiting bacterial
enzymes leading to an irreversible oxidation of SH groups (sulphydryl
group) of essential bacterial enzymes.
• Sodium hypochlorite is a strong base (pH>11). At 1% concentration, sodium
hypochlorite presents :- )
• A surface tension equal to 75 dynes/cm, 65.5 ms of conductivity, 1.04 g/cm 3
of density and moistening capacity equal to 1 h and 27 min.
• The antimicrobial effectiveness of sodium hypochlorite, based on its high
pH (hydroxyl ions action), is similar to the mechanism of action of
• The high pH of sodium hypochlorite interferes in the cytoplasmic
membrane integrity with an:-
• Irreversible enzymatic inhibition,
• Biosynthetic alterations in cellular metabolism and
• Phospholipid degradation observed in lipidic peroxidation.
• The amino acid chloramination reaction (reaction3) forming chloramines
interferes with cellular metabolism.
• Oxidation promotes irreversible bacterial enzymatic inhibition replacing
hydrogen with chlorine.
• This enzyme inactivation can be observed in the reaction of chlorine with
amino groups and an irreversible oxidation of sulphydryl groups of bacterial
• Thus, sodium hypochlorite presents antimicrobial activity with action on
bacterial essential enzymatic sites promoting irreversible inactivation
originated by hydroxyl ions and chloramination action.
TISSUE SOLVENT PROPERTY
• NaOCl possesses strong tissue dissolution property .
• This equals to that of H2SO4 and HCl.
• The solvent action of NaOCl has been attributed to its high alkalinity.
• Grossman and Meiman reported that 5% sodium hypochlorite dissolves pulp
tissue in 20 min to 2 h.
• 5.25% of NaOCl is capable of penetrating into the dentinal tubules &
dissolving the contents of tubules adjacent to the main canal.
• This is an extremely important property for an endodontic irrigant
because of the irregularities in the surface of the canal walls which prevents
contact by instruments.
Other Properties of NaOCl
• 1. Lubricant – for effective instrumentation.
• 2. Bleaching action on discolored teeth.
• 3. Increased permeability of dentinal tubules for easier penetration of an intra-
• Baumgartner and Cuenin, in an in vitro study, found that 5.25%, 2.5%, and 1.0%
solutions of sodium hypochlorite completely removed pulpal remnants and predentin
from uninstrumented surfaces of single-canal premolars.
• Although 0.5% sodium hypochlorite removed most of the pulpal remnants and
predentin from uninstrumented surfaces, it left some fibrils on the surface.
• The ability of an irrigant to be distributed to the apical portion of a canal is
dependent on canal anatomy, size of instrumentation, and delivery system.
• Trepagnier et al. reported that either 5.25% or 2.5% sodium hypochlorite has
the same effect when used in the root canal space for a period of 5 minutes.
• Spångberg et al. noted that 5% sodium hypochlorite may be too toxic for
routine use. They found that 0.5% sodium hypochlorite solution dissolves
necrotic but not vital tissue and has considerably less toxicity for HeLa cells
than a 5% solution.
• They suggested that 0.5% sodium hypochlorite be used in endodontic therapy.
• Bystrom and Sundquist examined the bacteriologic effect of 0.5% sodium
hypochlorite solution in endodontic therapy. In that in vivo study, using
0.5% sodium hypochlorite, no bacteria could be recovered from 12 of 15
root canals at the fifth appointment.
• This was compared with 8 of 15 root canals when saline solution was used
as the irrigant.
• Baumgartner and Cuenin also commented that “The effectiveness of
low concentrations of NaOCl may be improved by using larger
volumes of irrigant or by the presence of replenished irrigant in the
canals for longer periods of time.”
• On the other hand, a higher concentration of sodium hypochlorite
might be equally effective in shorter periods of time.
• Unpleasant taste
• Relative toxicity
• Inability to to move smear layer
• Corrosion of instruments
• Damages clothes
• On contact with Vital tissue:
– Inhibits neutrophil migration
– Damages Endothelial and Fibroblast cells
• Pashley et al (1985) and chang et al
– 0.5-1% NaOCl
Causes of complications
• Increased pressure application
• Wedging of the syringe
• Periapical bone destruction
• Lateral perforation
• Incorrect Working Length determination
• Inadvertant injection in to periapical tissue
• In to Maxillary sinus
• Hypersensitivity or allergic reactions
• Mixing of syringes (LA)
• Swallowing : pharyngeal oedema or oesophagal burns
• Paediatric : damage to Permanent tooth follicles
One month later
Infra orbital Nerve parasthesia
• There have been numerous reports of soft tissue complications as a result
of its inadvertent infection beyond the root canal system.
• Severe pain, Edema, Profuse hemorrhage both interstitially and through
This may be followed by (for several days)
• Increasing edema.
• Tissue necrosis.
• Secondary infection (rarely).
• Majority of cases, have shown complete resolution within a couple of
weeks. In some cases they may be long-term parasthesia or scarring.
Treatment for this type of emergency:
• 1. Remain calm and assist the patient in remaining calm.
• 2. Evaluate the reclined dental chair to decrease pressure from the
• a. For immediate relief of pain – nerve block and L.A.
• b. Wet, cold, compress – continually applied to the face – for relief
of pain and burning sensation and minimize swelling (for upto 6
Analgesics – after emergency treatment.
To control inflammation – corticosteroids immediately- i.v. for 3 days.
To prevent infection – antibiotics (1wk).
Heat packs and warm mouth rinse (after initial treatment).To improve
circulation to the area.
• Advise the patient concerning the anticipated swelling and ecchymosis.
• Give the patient both verbal and written instructions.
• Reassure the patient that he will regain his normal appearance within a
• is a cationic bis-biguanide that is usually marketed as
a gluconate salt.
• pH of 5.5-7.
• The most common preparation is with the digluconate
salt because of its stability and high water solubility.
wide spectrum antibacterial agent, and is active
against Gram-positive and Gram-negative bacteria,
facultative anaerobic and aerobic bacteria, spores,
viruses and yeast.
• Being a cationic agent, chlorhexidine electrostatically
binds to negatively-charged surfaces of bacteria,
damaging the outer layers of the bacterial cell wall
and rendering it permeable.
• The resulting penetration of chlorhexidine into the cell
causes precipitation of the cytoplasm, preventing
repair of the cell membrane and leading to the
destruction of the bacterial cell.
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
Suggested for irrigating canals of teeth that have been left open
for drainage, since the effervescence is effective in dislodging food
particles as well as other debris that may have packed the canal.
Being less effective as a solvent, H202 is also less damaging to
periapical tissues. Therefore, when procedural accidents have
caused either root or floor of chamber perforation or when the
apical constriction has been destroyed, it is the preferred irrigant.
Hydrogen Peroxide H2O2
• 1. Effervescence of the solution when in contact
with tissue and certain chemicals physically foams
debris from the canal.
• 2. Liberation of oxygen destroys strictly anaerobic
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 bactericidal 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 effervescence (bubbling) action which aid in mechanical
debridement by dislodging dentin debris and necrotic tissue particles and
floating them to the surface.
Advantages of using alternating 3% H2O2 with Naocl solution are :
1.Effervescent reaction (bubbles pushes debris mechanichally out of root
2.Solvent action of sodium hypochrorite on organic debris.
3.Disinfection and bleaching effect by both solutions.
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.
• Chelating agent is a chemical which combines with a metal to form a
• The purpose of a chelator is
Holding debris in suspension
smear layer removal
Chelators are formulated as
viscous suspension or an aqueous suspension.
A viscous suspension of a chelator advantageously
• promotes the emulsification of organic tissue
• facilitates the negotiation of the canal and
• is best used for holding debris in liquid suspension.
An aqueous solution of chelator
• best reserved for finishing the preparation,
• it removes the smear layer in an organic or inorganic film or both formed on the
walls of the canal by the cutting action of instruments.
Ethylenediamine Tetra Acetic Acid (EDTA)
• EDTA is a non specific divalent cation chelator,
chelating with calcium ions as well as with
• Nygard Ostby was the first who suggested the use of
EDTA for cleaning and widening canals.
• Facilitate canal identification,
• to clean and disinfect the dentinal wall
• to enhance chemomechanical enlargement of the
• EDTA results in increased dentin permeability which
augments the action of drugs.
• It can decalcify up to a 50-mm thin layer of the root
• If functions by forming a calcium chelate solution with the
calcium ion of dentin, the dentin thereby becomes more friable
and easier to instrument.
• EDTA is used during cleaning and shaping of the root canal and
is effective for achieving canal patency, enlargement,
debridement and disinfection.
• EDTA contains four acetic acid groups attached to
• The formula is as follows :
Disodium salt of EDTA : 17.0 g
Distilled water : 100.0ml
5N Sodium hydroxide : 9.25 ml
Effects of EDTA :
• EDTA is effective in softening dentin
• EDTA has distinct antimicrobial properties.
• EDTA is capable of causing a moderate degree of irritation.
• EDTA has no deleterious effect when used clinically as an irrigating solution.
• Irrigation with EDTA removes the smear layer.
• The extent of demineralization of EDTA is proportional to the exposure time.
• EDTA effects partial demineralization of dentin to a depth of 20 to 30 m in 5
• The most common chelating solution used for irrigation include Tublicid, EDTA,
EDTAC, File Eze and RC-Prep in all of which EDTA is the active ingredient.
CHX and EDTA
• Mixing CHX and EDTA immediately produces a white
precipitate * it seems that the ability of EDTA to
remove the smear layer is reduced.
• RC prep is a viscous chelator. introduced
by Stewart et al in 1969.
• Its principle ingredients are 15% EDTA,
10% Urea Peroxide and Propylene Glycol
in a base of Carbo Wax.
• 10% urea peroxide produces hydroxyl
radicals that oxidize sulfhydryl groups,
double bonds in proteins, lipids, and outer
membranes, and cause cell death.
• According to Stewart et al, urea peroxide
retains its antibacterial activity in the
presence of blood whereas aqueous 3%
hydrogen peroxide does not.
• Glycol is the lubricant that coats instruments and facilitates their movements in
canals, coating calcific material or in restricted canals that exhibits various
degree of calcification.
• It also protects the EDTA from oxidation by urea peroxide
• It is not water soluble.
• Irrigation with NaOCl following the use of RC prep removes smear layer and
produces significant effervescence, creating an elevator action to evacuate debris
that was dislodged from the root canal system.
• Since it is foamy, RC prep is placed on flutes of a file and carried directly to
walls of canal being prepared.
• Fehr and Nygaard-Ostby introduced EDTAC (N-O Therapeutics Hd,
Sweden), quaternary ammonium bromide, used to reduce surface tension
and increase penetration.
• The addition of Cetavlon (0.84 gm), a quaternary ammonium compound to
EDTA produce a solution called EDTAC, which has greater germicidal
• It has greater inflammatory potential to tissue as well.
• The inactivator for EDTAC is NaOCl.
• EDTA + texapon
• Edta is combined with sodium lauryl sulphate which results in decreasing
EDTA is combined with cetrimide ,cetyltrimethyl 1 ammonium bromide.it
helps in better cleaning of canals.
Hydroxyethylidene bisphosphonate (HEBP)
• Also called etidronic acid.
• Has chelating properties.
• The advantageous property of HEBP as chelating agent is that it shows
only short term interference with sodium hypochlorite.
• It contains a quaternary ammonium salt.
• It is a root canal chelating irrigant, N1-
• Has a broad spectrum of bactericidal activity
and the ability to chelate calcium, biologically
• Its low-surface tension and chelating effect aids
in biomechanical cleansing.
• Salvizol induces irritation of tissue at levels
similar to those of iodophores but less than those
of sodium hypochlorite or quaternary
ammonium compounds (Zephiran).
Bis-Dequalinium Acetate (BDA) / Solvidont
• It is used as a disinfectant and chemotherapeutic agent.
• It has
– Low toxicity
– Lubrication action
– Disinfecting ability
– Low surface tension
– Chelating properties
– Low incidence of post operative pain.
• It was marketed as Solvidont.
• BDA is recommended as an excellent substitute for NaOCl in
those patients who are allergic to NaOCl.
• The University of Malaysia reported a remarkable decrease in
postoperative pain and swelling when BDA was used.
• A new solution for the removal of the
• Mixture of Tetracycline isomer
(Doxycycline) + Acid (citric acid) +
Detergent (Tween 80).
• MTAD is an effective solution for the
removal of the smear layer and does not
change the structure of dentinal tubules
when canals are irrigated with NaOCl
and followed with a final rinse of MTAD.
• Tetracycline including Tetracycline HCl, Minocycline and Doxycycline are
Broad Spectrum Antibiotics that are effective against a wide range of
• Mechanism of action : Tetracycline has the following properties :
• It is bacteriostatic in nature. This property may be advantageous because
in the absence of bacterial cell lysis, antigenic byproducts (i.e. Endotoxins)
are not released.
• Low pH : Thus it can act as a calcium chelator and cause enamel and root
• Substantive medication : Becomes absorbed and is gradually released
from tooth structures such as dentin and cementum have prolonged
• It significantly enhances healing after surgical periodontal therapy.
• Acid : Citric acid were effective in removal of smear layer when used for
1 to 5 minutes.
• Detergent : The role of the detergent in this mixture is to lower the
surface tension and increase the generating ability of the irrigating
• Experimentation with various concentrations of these material showed
that a mixture of Doxycycline, Citric acid and Tween-80 was capable of
removing the smear layer from the surface of instrumented root canals
better than a combination of Doxycycline and citric acid alone.
• When EDTA is alternately used with 5.25% NaOCl, the smear layer is
completely removed in the middle and coronal thirds of canal preparations,
but this combination is less effective in the apical third.
• This is probably because of inadequate volume and/or penetration of the
solution into the apical portion of the canal during irrigation.
• The placement of MTAD with a cotton wrapped barbed broach allows
intimate contact of the solution even in the apical region of the canals and
improves debridement and less abrasive.
• MTAD also is less destructive to the tooth structure compared with EDTA
when used as a final irrigant. Close examination of the appearance of the
dentinal tubules showed higher amounts of erosion with EDTA.
Ruddle’s Solution :
• It contains
• Hypaque is a high contrast and injectable dye
• Used in medicine for - Angiography
• Hypaque is an aqueous solution of 2 iodine salts, diatrizoate meglumine
and sodium iodine.
• This is a radiopaque contrast solution to radiographically visualize root
canal system preparation procedure.
• The solution has the same specific gravity as NaOCl, is water soluble, has
a pH of 6.7 to 7.7, and is stable at room temperature.
• This composition simultaneously provides the solvent action of full
strength NaOCl, visualization (because its radiodensity is similar to gutta
percha), and improved penetration (because the tensioactive agent lowers
• Clinician can use endogram to visualize the microanatomy, verify the
shape and monitor the remaining root wall thickness during preparation
• Clinically, the solution is flushed into the root canal system of a tooth once
sufficient access to the pulp chamber has been made.
• The sodium hypochlorite portion of the composition will dissolve the pulp
and eliminate the bacteria, along with endotoxins that are harbored within
the root canal system.
• The solvent action of this solution progressively clears out the contents of
the root canal system, thus enabling the iodine portion of the composition
to flow into this vacated space.
• Endograms are useful in visualizing pathologic events, such as caries, certain
fractures, missed canals, and leaking restorations.
• Additionally, endograms can assist the clinician in managing internal
resorption, because the solution will map its location, size, and extent. In
endodontic nonsurgical retreatment, the endogram has shown promise for
improving diagnostics, treatment planning, and management of iatrogenic
• This method of visualization assists dentists in determining the best course of
action and in deciding whether to salvage or extract a particular tooth.
• Super oxidized water is saline that has been electrolyzed to form super-
oxidized water (hypocholorus acid and free chorine radicals)
• Supplied as Sterilox (sterilox Technologies,Radnor,PA) .
• This solution is nontoxic to biological tissues yet able to kill
• It was shown that it has potential irrigating solution.
• ECA was produced from tap water and saline
solution by a special unit that houses a unique floe
through electrolytic module .
• The fluid electrolytic module contains anode ,
made from titanium coated with ruethenium-oxide
,iridium and platinum and the cathode made from
titanium coated with pyro carbon and glass
• A diaphragm consist ultra filtration , electro
catalytic ceramics on the bed of zirconium,
yttrium, aluminium and nobium oxides separates
the anode and cathode.
• The solution exist in a metastable or equilibrious state after the production and
contains many free radicals and variety of molecules and ions in the metastable
state the solution has a very high oxidation potential .
• Two types of ECA was produced. One is anolyte which has a high oxidation
potential and catholyte is an alkaline solution with a high reduction potential
• It has strong chelating effect and detergent effect.
• These solutions remain in the metastable condition for about 48 hours before
coming to stable state.
• These solutions were active against Mycoba-cterium tuberculosi, M avium –
intercellular, M chelonae, E coli. E feacalis. pseudomionas aeruginosa. Bacillus
subtilis, Methicillin resistant staphylococcus aureus. candida albicans.
• Compared to NaOCl, the ECA solutions left a thinner smear layer with
a smoother and more even surface.
• NaOCl enhanced the opening of tubules predominantly in the coronal
and middle thirds of canals, whereas combination of ANOLYTE and
CATHOLYTE resulted in more numerous open dentine tubules
throughout the whole length of canals.
Chlorhexidine Gluconate gel
• Natrosol, a biocompatible carbon polymer, should be used as a gel base for
• It is a water soluble substance and therefore can be completely removed
from the root canal with a final flush of distilled water.
• Studies have confirmed the antimicrobial activity of chlorhexidine and
sodium hypochlorite demonstrated that the gel form may overcome the
inability of chlorhexidine to dissolve organic tissues by its mechanical action.
• So chlorhexidine gel has potential as a routine endodontic irrigant, (if
Natrosol is used as a gel base) because it has proved to be of low toxicity and
possess a wide antimicrobial spectrum.
• Powerful antimicrobial agent against bacteria, fungi, protozoa, and viruses.
• The advantages of ozone in the aqueous phase are its
Ease of handling,
Lack of mutagenicity,
Rapid microbicidal effects,
and suitability for use as a soaking solution for medical and dental
Oxidation mediated by ozone destroys the cell walls and cytoplasmic
membranes of bacteria and fungi. After the membrane is damaged by
oxidation, its permeability increases and ozone molecules can readily enter
the cells, causing the microorganism to die.
Endoquil (castor oil dete-rgent)
• Natural product derived from a tropical plant, Ricinus communis.
• Endoquil was developed in the Chemistry Institute of Sao Carlos (Sao
• Ferreira et al using Endoquil and 0.5% NaOCl in vivo as irrigating
solutions, observed a signi-ficant reduction in the number of colony
forming units for anaerobic microorganisms S. mutans and streptococci,
with no statistical difference betwe-en these two solutions.
• Richman in 1957 was the first to use ultrasonic scaler for apicoectomies.
• He was followed by Martin who designed a commercial system harnessing
the ultrasonic energy for the preparation and cleaning the root canal in
1976. This technique was termed endosonics.
Martin and Cunningham have coined the term endosonics, to refer to
endodontic treatment by supersonic, sonic or subsonic systems.
There are principally two different types of devices.
• The ultrasonic device which oscillates at a frequency of 20-30 KHz.
Eg. Caviendo, Piezo Ultrasonic.
• The sonic device which oscillates at a frequency of 1-6 KHz.
Eg. Endosonic air.
Method for Action
• Ultrasonic cleaning was described initially as Implosion or Cavitation.
• Cavitation occurs when ultrasonic file vibrates in a liquid to produce
alternating compression and rarefaction of pressure in the form of
growth and subsequent violent collapse of bubbles in fluid.
• A negative pressure develops within the exposed cells of the intracanal
materials (pulp tissue, bacteria, debris, metabolites, substrates etc).
• This causes an implosion or inward explosion that breaks these cells
apart inwardly and leads to their destruction.
• Since an irrigation / aspiration system is employed in the endodontic
equipment for ultrasonics, the broken cell part are washed out and then
removed from the canal system. The atomic bomb also works by the
• In 1975 Ahmad and group described another mechanism for ultrasonic
cleaning – Acoustical Streaming.
• Ahmad stated that cavitation cannot occur in closed environment as in root
canals for 2 reasons.
• For cavitation to occur in root canal the file must vibrate at a displacement
amplitude of atleast 135 micrometers and power setting in endosonic unit
was too low to produce this amplitude.
• Cavitation also depends on the free displacement amplitude of the file.
• This would be impossible to achieve during instrumentation because when
the file contacts the canal walls there will be reduction in amplitude.
• Acoustic streaming is produced around an
object oscillating in a liquid, that is it
creates small, intense circular fluid
movement (i.e. eddy; flow) around the
• It is characterized by the production of
large shear forces that are capable of
dislodging or disassociating lumps of
material. However the forces of acoustic
streaming are not sufficient to break up
the bacterial cell wall.
• The eddying occurs closer to the tip than in the coronal end of the file, with
an apically directed flow at the tip.
• Streaming forces occurring around the file disassociate clumps of bacteria
without disrupting them.
• The acoustic streaming generated by the file help reduce the number of
bacteria in the canal by removing the smear layer and debris harboring
bacteria, thereby facilitating their mechanical removal.
• The main advantage of ultrasonic files is that they move irrigant around the
canal and penetrate to the most apical extent of the instrument.
• The general conclusion is that acoustic micro streaming does occur around
the oscillating file. To be effective in this action, the file must be kept moving
at all times so that free oscillation can be maintained. Instruments are
generally moved circumferentially within the canal space.
• Two components
– PAD solution: Tolonium Chloride
– Save Dent Laser -635 nm
• Mechanism of action:
• Reactive Oxygen sp
• Disrupts membrane
• It includes PDT/LAT i.e photo dynamic therapy or light activated therapy.
Light of Photosensitizer Oxygen based free
specific wavelength Activation radical formed
Membrane damage Genetic damage Enzyme inactivation
• Optic fibre may be used to direct the irradiation to the intended side of
• Ease or use
• Duration -1-2 min
• Does not affect fibroblasts or Keratinocytes
• Laser is safe
IRRIGATION DEVICES IN ENDODONTIC
3.Manual Dynamic Agitation
(hand activated well fitting gutta
ІІ- MACHINE ASSISTED
6. Recent advance system
b. Light activated disinfection
C. Electrochemically activated
D.Oxidative potential water
Different sizes (1-20 ml)
Modifications of tip of the needles
C) Safe ended (A) (B) (C )
1.Syringe irrigation with needles/
27-31 gauge recommended
should not bind in the canal
not enough flushing action
deliver solution only 1 mm
deeper than the tip of the needle
B. NaviTip FX
used only as an adjuncts
Nylon bristles set in twisted wire
Can’t be used till working length
Dislodgement of radiolucent bristles
30-gauge needle covered with brush
3.MANUAL DYNAMIC AGITATION
Effect of “apical vapor lock”
Technique: Gently moving a well-fitting
master cone up and down in short 2- to 3-mm
strokes within an instrumented canal
1. changes in intracanal pressure
2. frequency of 3.3Hz, 100 strokes per 30
3. viscously dominated flow (mixing of fresh
spent solution with the reacted irrigant)
1. ROTARY BRUSHES
2. Continuous Irrigation
During Rotary Instrumentation
Self contained fluid delivery unit
uses a pump console, 2 irrigation
reservoirs & tubing
- no significant results in middle &
apical in cleaning efficiency
ІІ- MACHINE ASSISTED
A.Ruddle brush B.Canal brush
A. Rispisonic file
combines battery-driven vibrations
(9000 Cycle per Minute) with manually
operated irrigation of the root canal
ІІ- MACHINE ASSISTED
consists of a portable handpiece and
3 types of disposable polymer tips of
different sizes 10,000 cycles per minute .
IT is the simultaneous combination of ultrasonic irrigation and
instrumentation. it has been almost discarded in the clinical
Ultrasonically activated files have the potential to
prepare and debride root canals mechanically.
Files are driven to oscillate at ultrasonic frequencies
of 25–30 kHz in a transverse vibration
Two types of ultrasonic irrigation :
A. Active ultrasonic irrigation (AUI)
B. Passive ultrasonic irrigation (PUI)
ІІ- MACHINE ASSISTED
A. Active ultrasonic irrigation (AUI)
PASSIVE ULTRASONIC IRRIGATION (PUI)
During PUI, the energy is transmitted from an oscillating file or a smooth wire
to the irrigant in the root canal by means of ultrasonic waves.
The latter induces acoustic streaming and cavitation of the irrigant.
Irrigant Application Methods During PUI:
a) Continuous Ultrasonic Irrigation
Nusstein’s needle holding devices
needle is simultaneously activated by the ultrasonic
handpiece, while an irrigant is delivered from an intravenous
tubing connected via a Luer-lok to an irrigation-delivering
b) Intermittent Flush Ultrasonic Irrigation
Acoustic streaming cavitation
1-PUI is more effective than syringe needle irrigation in removing
pulpal tissue remnants and dentin debris.
2-smear layers were effectively removed from the apical, middle, and cervical
thirds of the canal walls by EDTA plus Cetavlon (EDTAC) and NaOCl by
using a size 15 file energized by ultrasonic agitation.
High-power ultrasound causes de-agglomeration of bacterial
biofilms via the action of acoustic streaming
Cavitation may produce temporary weakening of the cell
Removal of Bacteria:
B.PASSIVE ULTRASONIC IRRIGATION (PUI)
Removal of smear layer:
5. PRESSURE ALTERNATION DEVICES
A. The EndoVac System….
Multi-Port Adapter (MPA)
ІІ- MACHINE ASSISTED
(A) Macrocannula with handpiec
(B) Microcannula with fingerpiece
(C) Master delivery tip
(D) Tip of microcannula
The EndoVac System….
APPLICATION OF MICROCANNULE IN THE CANAL :
Advantages OF ENDOVAC SYSTEM
1.Safety:Less apical extrusion risk using the EndoVac system compared with needle
2.Efficacy:Better debridement 1 mm from working length using the EndoVac system
compared with needle irrigation
3.SUCCESS:Negative apical pressure irrigation system EndoVac results in
significantly less postoperative pain & necessity for analgesic medication than a
conventional needle irrigation protocol
B. The RinsEndo System
65 mL of a rinsing solution oscillating at a frequency of 1.6 Hz is
drawn from an attached syringe and transported to the root canal via
an adapted cannula.
Suction phase (100 times per minute)
higher risk of apical extrusion of the irrigant
ІІ- MACHINE ASSISTED
5. PRESSURE ALTERNATION DEVICES
• Regardless of which type or combinations of irrigants are used, it is
important to remember several points. The type of irrigant is only part of
the cleaning and shaping process. Gross removal of tissue is very
important to the dissolution of the remaining tissue, if the majority of the
tissue can be removed with files and initial irrigation, this leaves less
material to be dissolved.
• It is also important to remember that without proper access
preparation and canal enlargement, it is nearly impossible to get deep
enough needle penetration to allow the irrigant to provide the maximum
benefit at the apical portion of the tooth. These two are very important,
since even if we discover an ideal irrigant, it will be ineffective without
proper access and canal preparation.
• Since there is no ideal irrigant and since many different types and
combinations of irrigants have been used successfully in root canal therapy,
it is important for the practitioner to choose an
• Pathways of the pulp ,cohen, 6th & 9th edition
• Endodontics, ingle,6th edition.
• Endodontic practice, Grossman , 11th edi. & 12th edi.
• Lisha G, Kim JR. review of contemporary irrigant
agitation techniques and devices. J Endod
• Safety and Efficacy Considerations in Endodonti
Irrigation :A Peer-Reviewed Publication Written by
Gary Glassman, 2011