Endodontic Preparation Techniques, General Updates

What’s New in Endodontics for 2011?

Wishing you happy and successful endodontics in 2011

Wishing you happy and successful endodontics in 2011

Happy New Year to you wherever you are in the world. Here at the Endospot we like to keep you up to date with the latest in endodontic technology, so for the first post of the new year we’ll be discussing a new trend in endodontic file systems that seems to have been taken up by a few of the big companies. Previously I’ve mentioned adding additional files to your instrumentation protocol in order to create a smooth glide path. Now it seems that in the quest for an endodontic system that is faster and uses fewer files, the concept of a reciprocating file has been revisited.

Back in 1985, James Roane published an article on the balanced force technique and this is compulsory reading for any aspiring Endodontist (Roane et al. 1985). I won’t go into an explanation of the technique, but it uses a clockwise, anti-clockwise, clockwise motion to negotiate curved canals using stainless steel files. This process became motorized with the Introduction of the M4 handpiece, which is a reciprocating handpiece for use with stainless steel files. This handpiece has limited application but some Endodontists still use it for by-passing ledges in curved canals.

Back to the topic at hand. Dr Ghassan Yared has taken a step back to this concept of reciprocation to see if nickel titanium endodontic files can be used in a reciprocating motion to prepare canals. He published an article in the Journal of Endodontics in 2008 with his initial thoughts and experiences (Yared, 2008). At that stage he was using a single Protaper F2 to prepare canals. The canals were initially negotiated with a #8 hand file to length and then the reciprocating F2 file was used with a light apical pressure to prepare the whole canal. Of course, due to the variability of root canal anatomy, sometimes a larger file was needed to complete preparation – for example in distal canals of lower molars. The article also mentioned that sometimes the glide path had to be prepared with a #10 and #15 before the F2 would progress to length. These facts sort of negate the concept that this is truly a “one endodontic file system”, but I guess that in most of the cases, only one file was used. Anyway, have a read of the article yourself for a full run down.

Although there is limited research behind the process, there now exists a commercial version of the reciprocating files, developed with Dr Yared’s input (I’m not sure of his commercial interest in the system). A new file has been developed to replace the Protaper file. Apparently the use of the protaper had a couple of drawbacks in that it could be susceptible to fracture due to cyclic fatigue and a glide path was required.

The new reciprocating endodontic file system (VDWs is called RECIPROC) contains three files with a #25, #40 and #50 tip and is claimed to cut more efficiently than the protaper. IN cross-section, the file is similar in appearance to an Mtwo file. In instructional material Dr Yared claims that in the majority of canals only require one of these new endodontic files and that no hand filing is required. You do need to use a hand file to determine which reciprocating file to use.

Only one file to prepare a canal and no requirement for hand filing. Sounds like an endodontic dream right? Further reading of the material does in fact indicate that in some curved canals a glide path is still required using hand files and where there is an abrupt apical curvature hand files must be used to complete the apical prep, so unfortunately the system is by no means a panacea.

Apparently there is unpublished data available indicating that the reciprocating endodontic file system is faster at preparing canals, easier to learn and results in fewer procedural errors than rotary NiTi, so hopefully this data will be published soon so that we can assess it.

As well as GDW, Dentsply also has a reciprocating system on the market. I’ve had an opportunity to briefly trial the VDW and Dentsply files in plastic blocks. I’m told the files will be available commercially in Australia in a few months time so we’ll be able to test them out properly at that point and provide feedback.

If any readers out there have had experience with these files, I’d love to hear what you have to say. In the meantime, we’ll wait and see what research is published over the coming years. My take on this concept is that it does make sense to use the files in a reciprocating manner and I am looking forward to trialing the system. We really should be approaching each individual canal that we prepare as a unique task though, so I’m always a bit dubious about an endodontic system that has only a few files, but if the studies show promising results, this could become an important part of our armamentarium.

Roane JB, Sabala CL, Duncanson MG. The “balanced force” concept for the instrumentation of curved canals. J Endod. 1985 May;11 (5):203-11

Yared, G. Canal preparation using only one Ni-Ti rotary instrument: preliminary observations. Int Endod J. 2008 Apr;41 (4):339-44

Pathfiles
Clinical Tips, Endodontic Preparation Techniques

Faster, Easier, Safer Rotary Endo? Get Your Glide Path On.

Well, I don’t know if I’m going to help you improve the speed of your preparations, but I do want to make some comments about some files that I’ve recently had the opportunity to try (they may not be new to everyone, I work in China and things take a little longer to become available here). I’d like to make the point now that I’m not tied in any way to these files or the companies that sell them. In general, debates over what file system is best usually leave me a little bored and I’m not here to promote a particular brand or system. Everyone has their own favourite system and when you have experience with one type of file, then that is probably the one that will provide the best results for you. I also think it’s often quite difficult to take to a new file system as they all have a learning curve, a different feel within the canal and certainly different tolerances when it comes to fracture resistance.

Pathfiles

Thin files for narrow canals.

Anyway… The Pathfile NiTi files are only designed to prepare the glide path through the canal, and then you can use whatever system you prefer to complete the preparation. Want to know what I think is the key to quality rotary NiTi preparations? You guessed it, it’s the glide path. Most rotary Ni Ti files are designed to follow a path, not create one. It’s quite well accepted that if you can resist the temptation to pick up your initial NiTi file until your glide path is well and truly established, then you’ll find preparations are easier, smoother and probably faster. So, a rotary file system designed to create a glide path is a novel concept which challenges the assertion I just made.

There’s not much research around regarding these files other than an article that showed novice users could produce smoother glide paths in plastic blocks than endodontists can with stainless steel hand files. (Berutti et al, 2009) Sounds promising right? Well, I must admit to being a little hesitant when I first saw these files, because they are really narrow and well, you’re not creating a proper glide path before you put them in the canal. In my head, this meant susceptibility to breakage.

There are three files. A #13 (Purple), #16 (white) and #19 (yellow). The files are 2% taper, so they really are  quite narrow, but I guess that’s what makes them useful for preparing glide paths. The idea is to use a #10 stainless steel hand file to scout the canal (and confirm initial working length with EAL if possible), then use the #13, #16 and #19 to create the glide path. Working length is confirmed after this step. In practice, I found that they do a really good job of preparing the glide path, especially in narrow and curved canals e.g. MB2. The glide path that is produced is generally very smooth and makes the subsequent cleaning and shaping procedure easier and dare I say it faster. I don’t think you necessarily need to use all three files in all canals. Overall, you’re probably not going to prepare the canals any faster as you are now adding additional files to the process, and there is obviously going to be an increase in cost. But, if you are new to rotary NiTi, or looking to improve the consistency with which you can create a smooth tapered prep all the way to the apical foramen, then it might be worth giving these files a try. To be honest, these are the first products I’ve tried in some time that have had any sort of “wow” factor for me.

Using these files won’t be for everyone and more experienced practitioners probably have less need for them, but The Endospot is all about sharing information and helping others to improve their endodontics, so when I find something that I think might be worth discussing, then it will appear in your inbox. So, if you feel inclined to do so, get your friendly local rep (I think will be Dentsply in most places around the world) to drop a few samples off to you and grab some extracted teeth to get the feel of the file before diving into a live case. And remember to be gentle, these files are thin and going into narrow canals. If you do a search for Pathfile on youtube, you’ll find a couple of videos worth watching as well. If any readers have experience with these files and want to contribute some tips, then please leave a comment below.

References:

BERUTTI E, CANTATORE G, CASTELUCCI A, CHIANDUSSI G, PERA F, MIGLIARETTI G, PASQUALINI D. 2009. Use of nickel-titanium rotary pathfile to create the glide path: comparison with manual pre-flaring in simulated root canals. J Endod, 35, 408-412

Clinical Tips, Endodontic Preparation Techniques, Endodontic Re-treatment

How to Simply Remove GP for Endodontic Retreatment

Endodontic retreatment, remove GP

How are you going to remove the GP from this tooth?

Below is a video of a demonstration I gave at the Jiao Tong University Dental School in Shanghai. I was demonstrating a method for removal of GP from treated canals. The method that I describe is only one of many methods, but I think it is a good way to begin re-treating. Please watch the video and share your thoughts:

httpv://www.youtube.com/watch?v=D5SeDNOusV4