From: Terry Pannkuk
To: ROOTS
Sent: Tuesday, July 06, 2010 10:05 AM
Subject: [roots] Complex Molar Anatomy

This patient is a professor at UCSB and a great patient.   The patient was Asian with a very prominent zygoma and
unusual root anatomy with an MB root being bifid/almost two separate roots. The DB and MB1 were both well over 25 mm long.
The MB2 was 23.5mm and the Palatal 24mm long with a complex terminus.  I took a post-treatment CBCT which was interesting.
The buccal systems were quite ribbon shaped.  This type of root canal system geometry cannot be adequately described by a
taper size, apical gauge diameter, or working length.   In other words, what brand and size of rotary file that was used
is a meaningless discussion -  Terry






Very very nice case Terry. Nothing to say really but bravo. I for one know that proper radiographic documentation of
such cases is not easy and you show perfectly how CbCT can help in such cases. Furthermore you really put your finger
on the main issue that shaping in endodontics is all about adapting the instrumentation to the tooth and not the tooth
to the instrumentation. Warm regards, - Hani

PS: I am attaching a series of photos/xrays of an extracted second upper maxillary molar (anatomy similar to what you're
showing) that I have used in my courses to illustrate the difficulty of interpreting radiographs and evaluating tooth
anatomy and working length radiographically. I think they would/could complement your case rather well (just to
illustrate the anatomy). Please feel free to use them. (XR1 is ortho view, XR1 deviee is what would get by offsetting
the cone, and XR1 md is mesiodistal view, a clinically impossible angulation. The 2 others photos are rather obvious) - Hani






Nice images.  I’m going up to UCSF to teach the residents on Friday and I think I’ll add them as a very nice
compliment to the concept of root anatomy not being a tube.  The common perception is that a taper size,
glide path, and gauge apical diameter can be determined by two contact points and a conventional PA radiograph
which belies the true complex internal anatomy in 3-D.  For years many in academia denied the reality of
3-D interpretation which Schilder so elegantly described.  Mantras such as it’s what you take out of the canal
not what you put in .you can fill canals with bird crap and yada yada yada .simply serve to trivialize the
true clinical art which consists of astute perception and an understanding that 3-D interpretation facilitates
the cleaning via shaping while copious flushing of the contents to evacuate churned debris and contaminants.
A focus on file design, artificially imposed geometry, and a cookbook preparation mentality simply makes a clinican
wholly inadequate and distracted from the true goals of endodontic therapy; i.e. to debride, eliminate space, seal
the portals of exit of the root,  protect the attachment apparatus, and to definitively restore the dentition to
health and function. .   Thanks for your images!    - Terry

[This is a drive-by]
Ummm...yeah.

I can post case-after-case-after case just like these 25+ year recalls...from today.

What is missing is the 20+ year recalls on all the over-accessed, over-prepared, hogged out BU-style endo.
Surely 40+ years of BU alumni should be able to bury us with tens-of-thousands of 20+ year recalls.

But...No.
The obturation-driven shaping protocols result in beautiful looking endo that simply doesn't go the distance.

If the clinician takes a serious, unbiased look at the truly long-term cases, you will see that the things
listed below in blue are irrelevant at 20 years.  The word "seal" should simply be removed from the endodontic
dictionary, and using it speaks miles to the incongruities in peoples' mental models of what they do versus what
they actually do.

Preservation of the PCD trumps everything at 20+ years.

I mean...take a look...these teeth aren't even crowned...

The mantra should be:

"It's not what you take out or put in...it's what you leave behind." -  John A Khademy



Mantras such as "it’s what you take out of the canal not what you put in" you can fill canals with bird crap and yada yada yada
simply serve to trivialize the true clinical art which consists of astute perception and an understanding that 3-D interpretation
facilitates the cleaning via shaping while copious flushing of the contents to evacuate churned debris and contaminants.
A focus on file design, artificially imposed geometry, and a cookbook preparation mentality simply makes a clinican wholly
inadequate and distracted from the true goals of endodontic therapy; i.e. to debride,eliminate space, seal the portals of exit
of the root,  protect the attachment apparatus, and to definitively restore the dentition to health and function !

These words must be engraved on the wall next to the entrance of every endo dept at Dental Schools ! Well said/written Terry !
-  Valeri

Valeri,
I kinda wrote the chapter on "complex molar anatomy" about a decade ago.

http://www.amazon.com/Color-Atlas-Endodontics-William-Johnson/dp/0721690300

Due to limits imposed by the publisher, we had to limit the number of pictures and variations, but it's a start.


What is missing, because my chapter was an access chapter, is the shaping protocols.
Unfortunately, the shaping chapters and protocols are written by people who don't find this kind of anatomy,
like this patient from yesterday.  The MM was "shaped" to about a #20patent/#25 just short hand file.  1 year recall.

No, I didn't retreat the distal. - John A Khademi

John,

There are a lot of controversy in endodontics about what could be determined as a success.
See attached RX of a tooth which was treated back in 1989 and not crowned for 21 years.( I posted this picture several
times already ). Though it looks crap on RX it is doing fine without any clinical or radiological symptoms.
And here in Bulgaria I can show you many like this one I see everyday. They never been accessed properly, they never
been shaped and cleaned properly and they have been filled just with formaline - resorcine paste without any gutta-percha at all.

So as Dr.Mike Miller wrote:
I can do clinical/radiographic beautiful stuff that fails in 2-5 years  and I have some of my so-so  endo healing/healed
( not going there) after 20 + years and I see Sh*#@T that lasts  like this.  It all comes back to the patients ability to heal.

Endodontics is a dental speciality in which "success" is quite poorly defined if at all imho.

Having in mind findings of cbCT, Prof.Wesselink group studies and taking upon consideration my own clinical experience
what matters is not access, shaping, cleaning and etc. - it is the body's ability to heal - i.e. human immune system abilities.
That is like the role of immune system and antiobiotics when we treat dental infection - immune system is THE ONE which
eradicates/"treats" the infection and AB ONLY help it to do this faster.

As I wrote this earlier here - what we must do is to ensure the best possible conditions for the body's immune system to
heal the lesion - this means we should do exactly what Terry has said below in blue and we should not fill the canals
afterwards with bird crap, but with material which is helping the immune system to achieve healing and not adding more
irritating agents.

In accordance with that approach is also my opinion that we should combine whenever possible the regular endo with apico
when treating PA lesions larger than 5 mm.

And yea, I also do not touch something that works, in spite of the fact it may be looking filled short on RX ;-).

About shaping protocols - I do not think in almost all cases conicity of more than 4 % is needed, although I now routinely
work with 6 % conicity to stay safe on irrigation side :-). There were colleagues in Bulgaria who were telling me less
than 10 % conicity was crap :-), but I see after few years they have now became much more cautious on using conicity
larger than 6 % !  Large white lines may look good on RX, but are hardly of any help to already compromised tooth
which needs endo. - Valeri



John, any competent restorative dentist is going to remove as little tooth structure as possible in order to best restore
the tooth and this includes those of us restorative people doing a lot of endodontics.  All of the biomimetric stuff works
fine if you are working on virgin teeth but people like me practicing dentistry in the real world don’t get to work on many
virgin teeth.  We catch teeth with multiple attacks and injuries which are cumulative.

The vast majority of the teeth that I see needing endodontic treatment have already been blessed with multiple restorations
resulting in a large amount of tooth loss.  Of course any sane competent practitioner is going to remove the bare minimum
in order to reach their restorative goals.  That’s why I think this biomimetric hot topic is just another way to create CE cash.
Good restorative dentists doing adhesive dentistry are not using Black’s preps.  We are utilizing modern materials,
techniques, and adhesive mentality.  That equals minimal preps.  I don’t need to take a course to know this. - Guy

John's disconnect with reality is the same as Carr's.  I look at many of my own 20 year recalls; Carr doesn't claiming it's
too expensive and impractical since he moved his practice from Chula Vista.  Interestingly after I badgered the crap out him
to show some long-term recalls, his first one he posted had a lesion.  This was of course after he had insisted that
Endo failures don't occur after short-term validation of healed lesions.

Whether the scanned tooth I had sent Eric was perfed, or not, didn't clinically mat -  Terry Pannkuk