Скачать или смотреть Demo | How to manage ledges using rotary files ? | Dr. Waleed Kurdi

Endodontics is nowadays becoming more and more user-friendly with modern rotary or reciprocating files; however despite introducing new products, protocols are still prone to failure. One of the most common problems in endodontics is the formation of a ledge. This deviation from the original canal can be fatal for a tooth.

Managing a ledge can be a real challenge. Ledges lead to mistreatment and poor outcome. Main causes for ledges are improper instrumentation of a canal, pushing instruments or failing to use instruments in sequential order. When scouting a canal, one has to be very tactile and try not to push instruments. Sometimes its also connected with improper access.

First important issue is to understand how is it developed in a canal.

All NiTi instruments have two features, one bad and one good. Both are called "shape memory". On one hand it's good that files are flexible and adopt to the curvature of a canal. On the other hand, the problem occurs when we stop on the curvature with a rotating file. It’s proceeding while cutting on the outer part of a curvature. Time needed to develop a ledge depends on the construction of a file (more agressive file means faster ledge). It happens because the file wants to come back to its programmed shape (straight). Ledges can also be done with too rigid, fast or aggressive hand file introduction in the canals.

Knowing that issue can help us prevent from doing ledges, but sometimes it happens. So what to do in that situation. In order to pass a ledge, one have to pre-bend a file in a special way. Not as most of us do it. One has to use the advantages of a canal anatomy. What is good is that it's impossible to do a ledge on the inner curvature and this would help us pass a ledge more easily and more predictably. Ledges always occur on the outer curvature.

Mostly inner curvatures don't have any obstructions. Knowing that, we can use it to guide a steel hand file to pass a ledge very efficiently. First, what one has to do is to pre-bend a file in a fishing hook style. Then next step will be to advance it in the canal in a way that a tip of a file always goes toward the inner curvature.


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Ledge creation is one of the most common iatrogenic damages during the shaping.

As Clinicians we do prevent ledge creation using a “sweet” approach to the Endodontic anatomy during the shaping, but we also know how to manage the ledge when it is present, as there is a strong and scientific recognized relationship between presence of the ledge and negative outcome of the endodontic treatment. Aim of this article is to share with the community a rational and easy approach to manage the ledge using rotary files.

A ledge is a deviation from the original pathway of the canal created by the clinician during the instrumentation. Two factor are needed to create a ledge: the first is the presence of a curved canal, the second is an inappropriate approach during the instrumentation by the clinician.

Once the ledge is created, if the clinician continues to force the manual/rotary file, a perforation could be created. The ledge impedes access of instruments to the apex, thus canal blockage is caused by packing dentin chips and/or tissue debris: as a result, the portion of canal located apically to the ledge it is not shaped, cleaned and filled, and this is the reason why it is well recognized by the scientific community that there is a strong relationship between ledge creation and negative outcome of the therapy. According to the Literature we well know that working through contracted access cavities, forcing file/rotary file in curved canals and an improper WL registration are all factors that could lead to a ledge formation. Knowing the etiology of the ledge is really helpful to prevent its creation and during the treatment of curved canals helps us paying attention to all these factors.

Howewer it’s also important to know how to manage a ledge: in this article I will share with you some considerations and some clinical tips to properly manage a ledge, according with the Styleitaliano Endodontics philosophy.

To properly manage a ledge we do take into account these points:

The ledge is always in the external wall of a curved canal
It’s really important to know how deep is the ledge and the WL in order to choose the best operative strategy to complete properly the endodontic treatment
Prebendig a manual file is still a very important stage to manage a ledge
Martensitic rotary files at body temperature are very helpful to quickly and safely manage a ledge