Root canal Irrigation

1. IRRIGATION
DR SHANTA

2. IRRIGATION

3. COMPLEX INTERNAL ANATOMY

4. THE GOAL OF ENDODONTIC TREATMENT
• The goal is prevention or elimination of a microbial infection in
the root canal system
• success is dependent on successful infection control and/or
preserving the structural strength of the tooth.
• Planktonic microorganisms in the pulp cavity and coronalroot
canal may be readily killed by irrigants

5. IDEAL REQUIREMENTS FOR AN IRRIGANT
◆ Be an effective germicide and fungicide
◆ Be nonirritating to the periapical tissues
◆ Remain stable in solution
◆ Have a prolonged antimicrobial effect
◆ Be active in the presence of blood, serum, and protein
derivativesof tissue

6. ◆ Have low surface tension
◆ Not interfere with repair of periapical tissues
◆ Not stain tooth structure
◆ Be capable of inactivation in a culture medium
◆ Not induce a cell-mediated immune response
◆ Be able to completely remove the smear layer, and be able
todisinfect the underlying dentin and its tubules

7. ◆ Be nonantigenic, nontoxic, and noncarcinogenic to tissue
cellssurrounding the tooth
◆ Have no adverse effects on the physical properties of
exposeddentin
◆ Have no adverse effects on the sealing ability of filling
materials
◆ Have a convenient application
◆ Be relatively inexpensive

9. • ‰
Not weaken the tooth structure
• ‰
Be easily available
• ‰
Be cost-effective
• ‰
Be easy to use
• ‰
Have adequate shelf life

10. • In addition to these properties, if endodontic irrigants come in
contact with vital tissue, these should be systemically nontoxic,
noncaustic to the periodontal tissue and have little potential to
cause an anaphylactic reaction

11. FUNCTIONS OF IRRIGANTS
• ‰
Irrigants perform physical and biologic functions. They remove
dentin shavings from canals and thus prevent blockage of canal
apex
• ‰
Efficiencyofinstrumentsincreasesinwetcanalsandthey are less
likely to break in lubricated canals
• ‰
Irrigants act as a solvent of necrotic tissue, so they loosen
debris, pulp tissue and microorganisms from irregular dentinal
walls

12. • ‰
Irrigants help in removing the debris from fins, anasto- mosis,
accessory and lateral canals where instruments cannot reach
• ‰
Most irrigants are germicidal and have antibacterial action
• ‰
Bleaching action of irrigants lighten the teeth discoloreddue to
trauma or extensive silver restorations

13. FACTORS THAT MODIFY ACTIVITYOF
IRRIGATING SOLUTIONS

14. COMMONLY USED IRRIGATING SOLUTIONS
Chemical Agents Natural Agents
Tissue Dissolving
Eg: NaOCl, ClO2
Antibacterial Agents
Eg : Green Tea, Triphala
Antibacterial
1.Bactericidal (eg: CHX)
2.Bacterostatic(eg: MTAD)
Chelating
1. Mild Ph(eg: HEBP)
2. Strong ph(eg: EDTA)

15. NORMAL SALINE
• Advantages: It is biocompatible in nature. No adverse reaction even if
extruded periapically because osmotic pressure of normal saline is
same as that of the blood.
• Disadvantages:
1. Does not possess dissolution and disinfecting properties
2. Too mild to thoroughly clean the canals
3. Cannot clear microbial flora from inaccessible areas like acces-sory
canal
4. Does not possess antimicrobial activity
5. Does not remove smear layer

16. SODIUM HYPOCHLORITE
• NaOCl is clear, pale, green yellow liquid with strong odor of chlorine
• NaOCl is the most commonly used irrigating solution because of its
an antibacterial capacity and the ability to dis-solve necrotic tissue,
vital pulp tissue, and the organic components of dentin and biofilms
in a fast manner
• first produced in 1789 in France
• Dakinrecommended NaOCl as a buffered 0.5% solution for the
irrigation of wounds during World War I
• 1919 Coolidge introduced NaOCl to endodontics an intracanal
irrigation solution

17. AVAILABILITY
• NaOCl is used in concentrations varying from 0.5% to 8%.
• ‰
Unbuffered at pH 11 at conc. 0.5% to 5%
• ‰
Buffered with bicarbonate at pH 9.0 as 0.5% or 1% solution
• Between pH 4 and 7, chlorine exists predominantly as HClO,
the active moiety, whereas above pH 9, OCl– predominates.

18. MECHANISM OF ACTION OF SODIUM
HYPOCHLORITE
At body temperature, reactive chlorine in aqueous solu- tion
exists in two forms
• Hypochlorous acid (HOCl)
• Hypochlorite (OCl)

19. On coming in contact with organic tissues:
1. It forms- glycerol and fatty acid salts (saponification reac-
tion), resulting in surface tension of the solution.
2. It causes Amino acid neutralization reaction resulting in
formation of salt and water. pH decreases due to release of
hydroxyl ions.
3. When hypochlorous acid comes in contact with organic tissue,
it releases chlorine which combines with amino acids forming
chloramines. This chloramination reaction between chlorine
and amino acids causes interference in cell metabolism.

20. • Together these three reactions that occur in presence of
organic tissues lead to tissue dissolution and antibacterial
effect.

21. METHODS TO INCREASE THE EFFICACY OF
SODIUM HYPOCHLORITE

22. PRECAUTIONS TO BE TAKEN WHILE USING
SODIUM HYPOCHLORITE SOLUTION
• sodium hypochlorite is nontoxic during intracanal use but
5.25% NaOCl can cause serious damage to tissue if injected
periapically
• If sodium hypochlorite gets extruded into periapical tissues, it
causes
1. excruciating pain,
2. periapical bleeding and
3. swelling.

23. • As potential for spread of infection is related to tissue
destruction, medication like antibiotics, analgesics, anti-
histamine should be prescribed accordingly.
• In addition to these, reassurance to the patient is the prime
consideration

24. • Therefore, to avoid accidental extrusion of hypochlorite, care
should be taken to do passive irrigation especially in cases with
large apical openings.

25. ADVANTAGES
• Causes tissue dissolution
• Remove organic portion of dentin for
deeper penetration ofmedicament
• Removes biofilm
• Causes dissolution of pulp and
necrotic tissue
• Shows antibacterial and bleaching
action
• Causes lubrication of canals
• Economical & Easily available

26. DISADVANTAGES
• Because of high surface tension, its ability to wet dentin is less
• Irritant to tissues, if extruded periapically, it can cause
tissuedamage
• If comes in contact, it cause inflammation of gingiva becauseof
its caustic nature
• It can bleach the clothes, if spillage occurs
• It has bad odor and taste

27. • Vapors of sodium hypochlorite can irritate the eyes
• It can be corrosive to instruments
• It is unable to remove inorganic components of smear layer
• Long time of contact with dentin has determined effect
onflexural strength of dentin
• Exudate and microbial biomass inactivates NaOCl. So, continu-
ous irrigation and time are important when irrigation is done
with NaOCl

28. HYPOCHLORITE ACCIDENT
• Hypochlorite accident occurs when sodium hypochlorite gets
extruded beyond tooth apex.
• It manifests a combination of symptoms like severe pain, swelling,
and profuse bleeding both through the tooth and interstitial tissues.
• Clinical Features:
• Edema, ecchymosis along with tissue necrosis, paresthesia, and
secondary injection are commonly seen after hypochlo- rite accident.
Mostly patients recover within 7–10 days, but scarring and
paresthesia may take a long time to heal.

29. MANAGEMENT
• ‰
Immediate aspiration and application of icepacks
• ‰
Since infection because of tissue destruction can spread, prescribe
antibiotics, analgesics, and antihistaminics
• ‰
In severe cases, steroids and hospitalization for surgical wound
debridement is also indicated
• ‰
Home care instructions are given to patients like cold compresses to
minimize pain and swelling followed by warm compresses (after 24
h) to encourage healing

30. PREVENTION
• ‰
Use needles with closed end and lateral vents
• ‰
Tip of needle should be 1–2 mm short of the apex
• ‰
Never bind the needle in the canal, it should allow backflow of
the irrigant
• ‰
Oscillate the needle in the canal
• ‰
Do not force the irrigant in the canal