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Maxillary molar access - Courtesy ROOTS
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The opinions and photographs within this web page are not ours. Authors have been credited for the individual posts where they are. - www.rxroots.com |
From: Terry Pannkuk
To: ROOTS
Sent: Wednesday, March 25, 2009 10:43 AM
Subject: [roots] Access Demo from Today
I decided to take sequence pics of a maxillary molar access today in order to dispell all the bad advice floating
around that is likely to cause you to miss canals, inadequately clean systems, poorly obturate, and increase the
chance of separating an instrument.
I'm sure an argument storm is about to ensue.....so be it.
1. I rarely use ultrasonics on an access. Composite finishing burs are much more efficient and plane walls smoother.
2. Initial penetration is basically palatal to buccal toward the mesial and parallel to the mesial wall of the crown.
3. You can usually find the mesial pulp horn first because it is typically the most coronal, penetrate it and peel off
the ceiling toward the palatal pulp horn, then to the DB which is in a less predictable orientation.
4. Pull the main three corners out and flare for a direct line to the MB1, DB and P orifices. This is the complete
access outline for those favoring the dangerous "ship-in-a-bottle" philosophy.
5. Next use a football diamond to lightly "bowl" each of the three orfices out to the MB, DB, and ML-P line angles...
not deep..the idea is just to efficiently bowl out the mid-mass of dentin that otherwise would take forever to
eventually remove by other means.
6. Next use a cone composite finishing bur to "peel" away the orifice dentin overhang that restricts direct line entry
from the "diamond bowl" to the orfice...this is usually a thin overhanging slice of restrictive dentin.
7. At this point the MB2 on an uncomplicated case is very easy to identify. Don't even think of putting a file in any
of the canals yet. It's not time and you risk ledging!
8. Bowl out the clearly identified MB2 orifice with the football diamond toward the mesial marginal ridge in the same
way you did the MB1, DB, and P. You want to be fairly aggressive bowling it out wide but not particularly deep.
You will rarely over "bowl" although it is possible. The error is usually on the wimpy side.
9. Peel the overhanging lip off MB2 ceiling dentin to smooth it evening from the orifice to the "bowl" ledge on the
periphery just like you did on the other three canals.
10.It is now safe to use hand files.........MB2 last! (if the MB1-MB2 are confluent, extirpating the pulp from the
MB1 first is better and simplifies things)
***** Remember that you should always copiously irrigate with NaOCl. through out this process. Highspeed handpiece
use should always have waterspray blowing away debris. Up until you use the first hand files rinse with
EDTA after use of the high speed to clear away dentin debris and visualize orifices and grooves.
11.Recapitulate several times with precurved hand files series in each canal system not worrying about length but
knowing you're short of the estimated lengths.
12.Peel the orifices peripherally with the cone shaped composite finishng bur, or the flame tip if access is adequate
and the canal is opened up enough not to hit walls with the tip which will ledge. I tend to limit the use of the
flame tip to the larger palatal canals, rarely the DB, MB1, or MB2. The egg shaped composite finishing bur can be
used to bowl out orifices peripherally where the tooth is smaller, an exterior concavity exists, and you are worried
that the football diamond is too large and inappropriate for the presented root morphology.
13. Recapitulate with precurved hand files again. This centrically moves the orifices peripherally away from the
furcation and establishes a much safer angle for file entry.
14. At this point, you might consider use of rotary files if the recapitulations with hand files seemed to suggest
simply anatomy and a system form that allows the files to slide safely down the root without catching fins or
accessory canals. Many times I won't use rotaries until late in the cleaning and shaping process.
15. At this point it is safe to flare the coronal 1/3 with Gates. I use 1 through 4 but only passively.
The one slides down passively never pushed into the dentin so that it contacts the walls circumferentally.
The idea is just to make an oval canal system a bit more circular in cross-section which facilitates better
cleaning and convenience form to the mid-root and apical third. Just let the Gates go lightly where they go
lightly and use RC-Prep flooded in the pulp chamber which is a nice viscous irrigant that keeps debris in
suspension. Sometimes the Gates barely go into the MB2 oriice at all....don't worry about it.
The coronal flare can be developed a bit more later.
16. Take EAL (if necessary) and wire films for length measurement. At this point you may find out the MB2 joins
the MB1 at a coronal level and you can be very conservative with the shaping. If it doesn't and it's long,
bowl out the mesial wall a little more aggressively for safety, perform some more hand file recapitulations
and perrform the passive Gates again and begin the cleaning and shaping sequence.
Completion of final access design has been performed. You can see that the final access outline form has been
strategically and systematically developed which is why it should be considered a "SEE" access.
A "Strategically Extended Endodontic " access is also a "Systematically Extended Endodontic" Access...
also a "Smart (not Stupidly) Extended Endodontic" access, and above all a "Safely Extended Endodontic" access.
There are multiple ways to See a "SEE" access. :) - Terry
Nice presentation Terry, you are a great teacher, thanks a lot - Jose
Nice, Terry. More please - Guy
Nah. Simply unecessary, and untrue. Learn to use the mirror and place your rotary instruments visually.
Here is a patient I saw the same day Terry posted his pics. The angles of entry call for access extensions
kinda...well...oppositve of what Pannkuk is showing - John A Khademy
John, a couple of questions:
1. Considering the case you showed - the reason for endo was? Root caries, crack or resoprtion? -.
can't clearly seen from x-ray... just curious.
2. In the access like that, where are your reference points for measuring length? Let's say both
MBs are measured from where the probe hits palatal cusp incline as in your pic? and similarily to this:
DB is measured from mesial incline? and P from MB cusp tip?
3. How do you sequence preparation of the canals: do you shape one canal to final shape and get to the
next one or do you do prep them simultaneously (first one instrument to all canals, then next instrument
and so on till final shape)? - Dmitri
Shaping isn't necessarily cleaning unless the shaping facilitates the cleaning. Without access convenience
form to facilitate flushing of irrigant and evacuation of debris.....you just have nice looking rads hiding
the caca. - Terry
C’mon John. Let’s get real OK? Maybe YOU can do this with a Xenon illuminated access and an
Endodontist’s experience.
Anyone else without the equipment and skills that YOU have.and you get missed canals, missed anatomy and
busted files.
If you can do it.fine. But don’t for one second think that schools can teach it (I DO teach at schools) or
that it will result in raising the bar for the average RD. It will result in exactly the opposite. You can’t
treat what you can’t see.
John, you and I are buddies, but I will say publicly that if you come to town and try and teach that kind of
crap to my referrals , I will be all over you like Chris Brown on Rihanna.
Learn to use the mirror and place your rotary instruments visually. You know, I distinctly remember Herb
Schilder talking about finding MB2 at a convention lecture. One guy stood up and said he couldn’t even find
the MB root, never mind the MB2 canal. He might have meant MB1 but the look on Herb’s face was priceless.
- Rob K
This is about radiographic esthetics and not really cleaning the case. If you don't have the access
convenience form, the system isn't clean. Debris churns and rolls but isn't flushed out. Constricted access
also resricts file entry taking out the bend of a precruved file before it can efficiently contact apical
third walls and fins. You can tell this by the lack of irregular Hess anatomy filled apically.
You can shape or you can clean but if you haven't shaped to facilitate cleaning it doesn't matter how symetric,
and nice it is on the radiograph.....it's still crap-filled.
It's quite interesting how the same people that have argued for years against the "LOOK" when it really meant
something are the ones now showing off the "LOOK" that doesn't. :):):) - Terry
