Apical curvatures

One of the major disadvantages of using metal needles is the impossibility to deliver the irrigant in the apical portion of the root canal. What’s more, as stainless steel needles are not able to penetrate in the most apical areas and follow accented curves, the `vapor lock´ effect is increased. The `Vapor Lock´ is a physiological effect that implies an air entrapment in the apical part of the root canal while performing irrigation in the coronal and middle thirds, which avoids contact from the irrigant with the apical root canal. IrriFlex® can overcome this problem because it easily reaches the apical part of the root, mostly adapting to any shape and delivering the irrigant up to working length if desired, which may increase our disinfecting procedure.

Traditional metal needle vs IrriFlex® plastic needle

The following in-vitro video with resin blocks shows how a conventional stainless steel needle is unable to reach the apical third and get stuck into the curvature, while IrriFlex® perfectly follows the anatomy reaching the apical part.

Fig. 1

Double curvatures

If IrriFlex® represents a great advantage when delivering the irrigant in presence of apical curvatures its efficacy in cases of double curvatures is incredibly higher if compared to regular metal needles. The following case shows a maxillary first premolar with a double curvature which was instrumented with Trunatomy system up to 26.03. IrriFlex® was used to irrigate the narrow root canals up to desired working length due to its flexibility.

Fig. 2

Deep splits

One of the main advantages of IrriFlex® is the possibility of pre-bend the needle as desired in cases where multiple canals are encountered as for example in three-rooted maxillary premolars or mandibular premolars with deep splits. The following case shows a mandibular premolar with a deep split in the coronal third where 3 root canals are found. IrriFlex® permits to easily irrigate the different root canals just pre-bending the needle which is extremely soft and allows its constant manipulation without being damaged.

Fig. 3

Anatomical variations: isthmuses and lateral canals

Cleaning and disinfection of root canal inter-communications is one of the most challenging procedures during root canal treatment. Isthmuses and lateral canals represent a potential space for the reservoir of microbes and the accumulation of debris produced from mechanical preparation of the root canal system. The following case shows a first mandibular molar in which after instrumentation, continuous irrigation with IrriFlex® was performed. After root canal obturation, observe how the anatomical complexity of the root canal system is revealed showing the presence of a lateral canal at the mesial root and the presence of an isthmus at the distal root.

Fig. 4

Second mesiobuccal canals (MB2)

Another main advantage of IrriFlex® is that it easily penetrates into a narrow, curvy and complex canal as it is the 2nd mesiobuccal canal of maxillary molars. Achieving continuous patency in such canals is essential because MB2 has been described as a difficult canal to be scouted, negotiated and finally instrumented. Therefore, IrriFlex® allows the clinician to perform a constant irrigation having the canal free of detritus which may impede a proper instrumentation and thus irrigation into the apical part. The following case describes a regular root canal treatment in a first maxillary molar with the presence of a narrow MB2 canal that merges with the main mesiobuccal canal in the middle third, which was continuously irrigated with an IrriFlex® needle.

Fig. 5

C-shaped canal system

Second mandibular molars are the most prevalent teeth where c-shaped anatomy is encountered. The anatomical configuration consists in the presence of isthmuses and fins that connect the main root canal. This morphology presents a great challenge in all steps of root canal treatment specially during root canal disinfection. 

In such cases, IrriFlex® is without any doubt a useful tool which can explore the C-shaped anatomy performing a continuous delivery of the irrigant while activating it with agitation as if manual dynamic activation was performed with a gutta-percha point. 

The following case shows the initial and post-operative radiograph of a root canal treatment in a mandibular second molar with a C1 configuration which was instrumented with Wave One Gold 20.07 and where continuous irrigation with NaOCl 4.25% using IrriFlex® was performed. Check the status of the pulp chamber after performing the agitation of the irrigant.


IrriFlex® has come to stay and change our current irrigation protocols during root canal treatment. The use of this flexible needle implies a series of advantages when compared to traditional metal needles such as an easy insertion into the apical third of the root canal system adapting itself to any curvature present while delivering the irrigant in a safe way. Furthermore, IrriFlex® allows the clinicians to pre-bend the needle according to the desired anatomy of teeth and favours a continous agitation of the irrigant avoiding the undesired `Vapor Lock´ effect while removing all debris and remnants from the root canal system.


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