SURE THAT many of you have tried using the EZ-Fill technique in doing your
endodontic procedures. With every new technique there is always a
learning curve. Dr. Musikant has explained the steps in using the
SafeSiders reamers more than once in recent newsletters (and you can download
his full explanation). Do not be disheartened if you are not
able to create the perfect-looking canal. It is okay to go back on
certain size reamers to open up the canal wide enough to get the Peeso
reamer down the canal. The SafeSiders reamers are great instruments,
but their results are only great if the dentists using them are able to
adapt to certain situations.
In this article, I will explain the different approaches
to certain root anatomy and complicated situations as they occur.
I hope that it will help you to understand the methodology behind the technique.
This understanding will in turn make root canal treatment easier and more
I tend to deviate a little from the method that
Dr. Musikant teaches. You have to find a pattern that is comfortable
for you to work with. I follow the same initial sequences for every
case I encounter. I will then determine the next step upon analyzing
the situation Iím in at that time. You cannot expect the technique
to work out the same way in every case. The only thing you can expect
is the end result, which is a continuous tapered root canal filling using
a single gutta-percha cone.
I do mostly molars, so I will explain the steps
I use in performing the root canals. I would start out with a #6
reamer to get to the apex. I continue to instrument the canal with
a #8 and a #10 reamer until the canal feels loose. I will then get
the working length with a #15 reamer, because the apex locator gives a
better reading with a snugly fit reamer in the canal. Once I have
the proper working length, I then proceed to instrument the canal up to
#25 to the apex. The chamber is filled with sodium hypochlorite the
entire time to aid in the cleaning process and to prevent debris impaction.
Now I will open up the canal using a #2 Gates
Glidden (GG). The GG should have no problem following the curve of
the canal because the shank is a little flexible. The width of a
#25 reamer is wide enough to allow the GG to follow. Do not use force
to push the GG into the canal. Just use a gentle pecking motion to
drive the instrument down the canal. This pecking technique will
prevent debris impaction. The reason I do not go to the #2 Peeso
reamer is that the canal is not wide enough at this point to allow a smooth
cutting. You may have encountered this problem once or twice.
After I have widened the canal with the GG, I irrigate the canal to remove
the debris. I then go back with a #10 reamer to break up the debris
created by the GG.
Next I use the #2 Peeso reamer (PR) to widen
the canal. The PR should cut smoothly down the canal by following
the path of the GG. Remember to lean the PR toward the wall away
from the furcation. Do not force the PR, but use a light pecking
motion. It is okay if the PR does not go far into the canal.
It is not important at this point. Remember to irrigate the canal
to remove the debris. I then re-instrument the canal starting with
the #10 reamer to #30 to the apex. The reason I go back to
#10 is to make sure the apical foramen is patent.
This is the general sequence of steps I go
through with every case. Now during these steps, certain situations
arise in which you have to deviate a little from the general sequence.
Letís say that you used the GG with a little too much force to go down
the canal and found out that you canít get back into the canal again.
You have probably caused debris impaction in the canal. What you
want to do is to make sure the chamber is filled with sodium hypochlorite.
Next, go back in with a #10 Hedstrom and gently turn clockwise one revolution
and pull out. This procedure will help you to remove the debris and
renegotiate the canal. Do not rush and push too hard or you will
make your own canal instead.
If you used too much force with the PR and canít
get back into the canal, you have probably caused a little ledge at the
curve of the root. In that case, you would take a #15 SafeSiders
reamer and bend the tip a little bit. Insert it into the canal and
gently twist it back and forth slowly until it renegotiates the canal.
Continue in the same manner up to a #30 reamer. If the ledge is too
tight for you to get the NiTi files to engage the canal, you will have
to go back in with a Hedstrom and strip the curvature a little bit to allow
the NiTi file to engage. This procedure will take a little time,
but donít rush.
If you are working on a molar with a sharp curve
like the one in Figure 1, do not use the GG or PR until you have opened
up the canal to at least a #30 reamer. The reamers do not have to
reach the apex at this point as long as they go past the curvature.
Now go in with the GG slowly with a gentle pecking motion. Donít
worry if the GG doesnít go in too far. Itís not supposed to because
of the sharp bend in the root. Now irrigate the debris and make sure
that the chamber is filled with sodium hypochlorite. At this point,
I make another deviation from the general steps. Take a #10 Hedstrom
and instrument to the apex using the technique of making one clockwise
revolution and pulling out. This technique will allow you to widen the
canal and reduce the sharp curvature at the same time. Follow this
with a #15 SafeSiders reamer to open up the canal for the #15 Hedstrom
to engage. Continue with this SafeSiders-Hedstrom routine until you
get the #30 Hedstrom to the apex or close to it. Remember to irrigate
well after each SafeSiders-Hedstrom set to prevent debris impaction.
Now use the #2 GG, and it should be able to go a little farther down the
canal. After that, go in with the #2 PR with a light pecking motion.
Do not push when you feel resistance. After all these steps are completed,
take the orange NiTi 30/.04 and instrument the canal to the apex with a
watch-winding motion. You do not have to get the brown NiTi 25/.08
down to the apex. You just need to get it past the curvature to give
a continuous-taper shape to the canal.
The most important part of the instrumentation
process is the constant contact of the sodium hypochlorite with the canal
wall. It will assist in debris removal and also in removing pulp
tissue in lateral canals and apical fenestration as seen in Figures 2 and
3. What I normally do is to flood the chamber with the solution and
leave it there while I instrument the canal. The bi-directional spiral
will coat the wall very well and force the EZ-Fill cement to fill in the
lateral canal and apical fenestration.
I hope that this article will help you in
the future if you happen to encounter such problems.
FIGURE 1: Upper molar with
a very curved mesial buccal root.
FIGURE 2: Upper first premolar
with a lateral canal filled with EZ-Fill cement.
FIGURE 3: Lower second molar
with a distal root apical fenestration filled in with EZ-Fill cement.