Irrigation : The Powerful weapon
Dental Post – 1
#Irrigatewisely
The success of endodontic treatment is completely relied on the principle of 3 dimensional cleaning and shaping root canal system by complete eradication of pathogenic microorganisms and necrotic pulp. And IRRIGATION plays central role in endodontic treatment.
How Irrigation works? Why it is important step? Which all solutions and methods are used ? And in what sequence it is used ?
I will try to explain this topic more practical point of view because more of us don't know how to apply our theory knowledge when it is needed while doing cases. Let’s start.
What is irrigation and how it works?
Irrigation means flushing the root canal space with different irrigating solutions to remove all the inflamed pulp tissue and debris and also to reach all the inaccessible areas where mechanical cleansing doesn't work well.
During the cleaning and shaping phases of an endodontic treatment it is possible to distinguish chemical and mechanical cleansing. Mechanical cleansing, in addition to the removal of necrotic or vital pulp tissue leads to the formation of a thin layer of debris known as " smear layer". This SMEAR LAYER is made up of potentially infective organic and inorganic substances that must be removed from the canal walls, dentin tubules and root canal branches with the aid of root canal irrigants that is chemical cleansing.
Methods of Irrigation –
There are mainly four types :
1. Apical Negative Pressure System (ANP) - This system is introduced to simultaneously release and remove the irrigant. These systems comprises a macrocanula for the coronal and middle portion and a microcannula for the apical portion, which are connected to a syringe for Irrigation. This system has the purpose to ensure a constant and continuous flow of new irrigant in the apical 3rd with safety and a lower risk of extrusion.
• Examples – Endovac system, Endoirrigator plus
Cost Effective Alternatives : You can attach metapex tip to suction tip which will remove the irrigant from the canal and normal needle syringe to release irrigant in the canal
2. Manual Dynamic Agitation (MDA) - It is a simple & cost effective technique which involves repeated insertion of a well fitting gutta percha cone in short vertical strokes to hydrodynamically displace & agitate an irrigant. Here the canal is filled with 5.25% sodium hypochlorite (NaOCl) & push pull strokes are performed manually, 1-2 mm short to the working length at an approximate rate of 100 strokes/min for minimum 30 seconds to 1 min.
3. Ultrasonic Irrigation system – Ultrasonic irrigation of the root canal can be performed with or without simultaneous ultrasonic instrumentation. When canal shaping is not undertaken the term PUI can be used that is ‘Passive ultrasonic irrigation'. PUI is the non cutting technique which reduces the potential for creating aberrant shapes in the root canal ( like apical zips, perforations). This method is more effective than sonic activation and manual Irrigation as it creates a higher speed and flow volume of the irrigant in the canal during Irrigation thereby eliminating more debris, producing less apical packing, better access of the chemical product to accessory canals and even the flush effect is produced by ultrasonics but not manual irrigation.
• Example – Endoultra
4. Sonic activation system - Most actual systems have smooth plastic tips of different sizes activated at sonic frequency by a handpiece . This effectively clean the main canal, to remove the smear layer and to promote the filling of a greater number of lateral canal. Recently introduced technique uses a syringe with sonic vibration that allows the delivery & activation of the irrigant in the root canal at the same time.
• Example – PATS system ( air sonic activation), Endoactivator system, MM 1500
5. Needle Irrigation (NI) - In this method, solutions are delivered by a syringe and a 30 guage needle. The tip is placed as deep as possible( but 1-2 mm short to Apex) in the canal without wedging to permit backflow of the irrigant.
- Other cost effective alternative for activation of irrigant:
1) You can use ultrasonic activator tip which can be attached with your ultrasonic scaler.
2) You can attach Endoactivator tip to waterpik flosser.
3) 'U' files – They can be used in conjunction with 120° file holder that is endochuck which can be fitted onto an ultrasonic scaler handpiece.
“Apical vapour lock effect” :
Apical vapour lock is consistently formed during routine endodontic irrigation which impedes irrigant penetration till the working length thereby leading to insufficient debridement. This problem can be minimised by negative pressure irrigation OR techniques such as sonics/ultrasonics, Laser induced activation.
