From: Harald Prestegaard
To: ROOTS
Sent: Friday, March 04, 2005 6:10 PM
Subject: [roots] Interesting canal anatomy 46

Interesting canal anatomy 46
Asymptomatic periodontitis.
MB/ML 23.5 mm ref. Buccal cusp ProTaper S1,S2,F1;F2 apical prep with NiTi Flex nr.40
DB/DL 23.5 mm ret. Buccal cusp ProTaper S1,S2,F1 - F3 apical prep with NiTi Flex nr. 50
Irrigation 5% NaOCl, 17% EDTA and final rinse 5 min. with Consepsis.
Obturated with cold lateral condesation Epiphany/Resilon.

Harald Prestegaard
Norway



Dear Harald !

Very nice case. If you don't mind me commenting the DL canal looks quite short, was this where the EAL was showing the anatomical apex/constriction to be ?
I use very much the same technique. - Thomas

Inspecting the x-ray again I may agree.
I think it was very difficult to see on the X-ray exactly the apex on the distals.
So I used the EAL reading.
When I look now it may be approx. 1.5 mm too short.
This is the nice thing about roots getting a lot of another views. - Harald

These three rooted mandibular molars are very common on native
americans and asians.  We see these all the time, along with the C
shaped variation of the lower second.  From a few weeks ago.  Is yours
a little short? - John A Khademy



Dear John, This look realy nice or should I say geourgous.
What kind of shaping and obturating technique.
I did not think that I was short but I understand what you mean looking at
the X-ray again. I thought it was difficult to be sure from the X-ray so I
followed the EAL  only in the distals and I got consistent readings in both.
SO HOPEFULLY I HAVE SHAPED;IRRIGATED AND OBTURATED WELL ENOUGH. to get this
working - Harald

John, I like this post op.
Could you let us know how your intrumenting sequence, please? Thanks - Marcos Arenal

Copy of a post to TDO where I was asked the same question.
Phil, Thank you for the compliment.  All I really tried to do was not screw
it up.  Truth be told, I did not know about the reverse curve on the
DL root.  I just kept is small as usual with this little root.

It seems like no one here follows instructions, and I will be at the
front of the line to admit it.

Like most of us, the spectrum of cases we see ranges from difficult on
up.  No one "cookbook" method, or set of instrumets solves all the
problems.  In my hands, Profile Series 29 .06's are the bread and
butter, supplemented by GT's in  my favorite sizes of 20/.08, 30/.08,
40/.10.  I keep telling myself to try some of the "sharp" files, but
I'm a chickenshit.

1) Gain access and locate canals, and suspected location of canals
that are not readily visible

2) GG accessible canals 1-3 short GG.  Not trying to shape, just get funnel.

3) Go find the suspects.  Usually too small to GG.

4) Negotiate to full apex locator length.  If there is a fighter (usually MB2) bail on that for now.

5) Negotiate to full apex locator length to #20.  Don't cheat.  #20. All the way.

6) Series 29 profile #2, #3, #4 as far as they want to go.  Repeat once or twice.

7) If the #2 has not gone to full length, we are probably binding coronally.  Bring in #5 and #6.

8) Hang the #2 long, now #3 goes.  #3 long, #4 goes.  If appropriate,
#4 long, #5 goes.  We are now at least to a 20/.06 on these canals. Thin, but fillable.

9) Go back and deal with the fighter.  After fighting, then following
Herbranson's advice about not doing the hard canal first I continue to
be amazed at how the initially difficult canal somehow got easier.

10) Bring out a fresh set of instruments and prep the fighters as above.

11) Assess shapes ala Buchanan and guage.  Use GT's as needed to
increase shape and/or apical diameter as appropriate in large and/or
straighter roots.

The problem with Profiles and GT files is that they are blunt to start
with and get even duller.  It is not uncommon for me to use two or
even three sets of #2 to #4 Profiles (6-9 instruments) on an upper
molar.  The advantage is that with the U-blade, it is almost
impossible to strip or straighten a canal.  They just don't cut unless
they are wedged in.

This tooth had the following shapes:

MB, MB, D #4 Series 29 .06 (essentially a 20/.06 GT) DL root #2 Series 29 .06 about 1mm long (with prayer)
(again essentially a 20./.06)  - John A Khademy


Short? No. It's perfect. DougR

Wow, great work. - Guy W. Moorman, Jr. DDS

Very nice, how did you instrument the 'S' shaped canal? - Carmen cohn

Great case and case report! - DanS

John: Great post and explanation of your protocol....thanks!
judging from your cases, you must be carrying the same wallet as Samuel L.
Jackson in Pulp Fiction....remember the restaurant scene?....))
with every system there is a learning curve and it is amazing to me that so
many can switch back and forth between different file systems. For instance
K3 is my main file. I have learned when to lean, when to push and when to
just let it drop in the canal. I know more about these than any other file.
That's my bow and arrow. I mix in the GT's & ss files but that's it
Personally, I hated the profile system. Broke too dang many of them.
But I was an ignorant who didn't know how to use them.
(there you go Barry....right down the middle of the plate)
Not only they were dull, I always felt like they were burnishing the canal
walls rather than "filing" it.
Having said that, when You, Schwartz and Stropko use this system, who am I
to argue? - ahmad

John, Your use of so many files reminds me of my technique.  I was impressed by
watching and listening to Rosenberg at his office this past weekend.  He
spends probably 45 minutes on his typical molar access prep.  Included in
this process is going into the canals 2-3 mm's with ultrasonic tips moving
the canal wall way toward the safe side.  This provides for way better
straight line access than I was achieving with my gg's and peezo.  After he
has his 20 hand file to length and has spent the time on straight line
access, he frequently can finish the canal prep with only 1-3 rotary files.
I tried it on some ext'd teeth and I was amazed.  He usually starts with an
S2 protaper and then finalizes his rotary use with a 20/.08 GT file, and
sometimes a 20/.06.  On really tight canals, he'll sometimes use the S1 also
if the S2 won't readily go to length.   - Mark