1. Endodontic Irrigants
 Irrigation has been performed in conjunction with endodontic therapy for
many years. One of the primary reasons for irrigating the root canal
system is to ensure cleaning of the canals prior to obturation. This
cleanling involves both:
 elimination of microorganisms and removal of organic matter
Desiared functions of irrigating
solutions
 _ Washing action (helps remove debris)
 _ Reduce instrument friction during preparation (lubricant)
 _ Facilitate dentin removal (lubricant)
 _ Dissolve inorganic tissue (dentin)
 _ Penetrate to canal periphery
 _ Dissolve organic matter (dentin collagen, pulp tissue, biofilm)
 _ Kill bacteria and yeasts (also in biofilm)
 _ Do not irritate or damage vital periapical tissue, no caustic or cytotoxic
effeActs
 Do not weaken tooth structure

2. Benefits of irrigation during
endodontic work
 Making a wet environment during preparation ..the dentin shaving
floating to the chamber
 Files and reamers are less likely to break when the canal is wet
 The irrigant that are typically used have the function of necrotic tissue
solvent
 The irrigants loosen depris, pulp tissue , and M,O from irregular dentin
walls
 Most irrigants are germicidal
 Also have ableaching action to lightens teeth discolored by trauma
post operative darkness
Useful irrigants
Sodium hypochlorite(naocl)
 Most widely used.
 the pH of sodium hypochlorite is near 12.
During the treatment of a root canal,
the increase in pH likely creates
a microenvironment that is not
particularly hospitable to bacteria in the
root canal system.
 . It is potently antimicrobial and dissolves organic material.
 It also affects -- but doesn't remove -- the smear layer. Removal of the
smear layer enhances obturation and decreases apical leakage.
 NaOCl may also cause pain and injure periapical tissues when it extrudes
through the apex.

3. EDTA and CA
 Complete cleaning of the root-canal system
requires the use of irrigants that dissolve
organic and inorganic material.
As hypochlorite is active only against the
former, other substances must be used to
complete the removal of the smear layer
and dentin debris.
 EDTA and CA effectively dissolve
inorganic material, including hydroxyapatite.
EDTA is most commonly used as
a 17% neutralized solution (disodium EDTA, pH 7), but a few reports have indicated that
solutions with lower concentrations (eg, 10%, 5%, and even 1%) remove the smear layer
equally well after NaOCl irrigation