From: Michael Moran
To: ROOTS
Sent: Wednesday, March 02, 2005 10:27 PM
Subject: Re: [roots] Question for Mark Dreyer on Squirting

Dear Mark,

Would you care to outline the relevant points of canal preparation when intending to use the squirt technique, or would
that be letting out some of Joey D's and John Stropko's secrets into the public domain?

I've been using the Obtura II alone for obturation since the Roots discussion not long ago regarding having adequate
thermoplasticity at the apical constriction when using the System B technique outlined by Dr Buchanan.  I'm making sure
there is a very definite apical constriction to compact against, injecting GP with the Obtura, following up with the
System B technique as per Dr Buchanan (but with a slight variation here as I'm also using a Schilder type condenser to
compact before reinjecting again, repeating the downpack to a slightly more coronal level with a System B tip to ensure
there is union between the first and second increments).  At least this way I'm confident the GP at the apex is warm when
I compact vs. a cold GP point heated with the System B tip to within 3 - 4 mm of the working length  - Michael Moran


John & Joey have never minded that I share some of their info.  As much as I’ve learned online, this is one area that I
feel I really benefited in having a hands on course.  I recommend you consider their courses.

Here I am describing what I learned from John & Joey as per the obturation process.  The shaping process I describe isn’t
exactly how they teach it but is pretty similar.. Mark

Squirt obturation techique

First of all prior to doing this technique, the canal should be shaped with gg's 1-4, or 2gg and 2 peezo.  Then the
apical should be shaped so as to provide continuity of taper.  I use Protapers S1, S2, F1, F2, F3, and if the foramen
is larger than 30 then I do some extra refinement with either .02 or  .04 taper k3 files.  I choose the appropriate k3
file based on the size of the foramen and the degree of curvature of the canal.

Needed supplies:

Obtura Gun
Sterile Fine paper points
20 gauge obtura needles
Kerr's EWT sealer
Blue/Black Dovgan niti condensor

Steps in squirt technique:

1. Canal must be as dry as possible-alcohol, evacuate, dry-paper points, stropko to air dry
2. Apply Kerr's Sealer to the canal walls with a paper point then dry off excess using dry paper point.
3. Introduce obtura tip into canal as far as it wants to go.  Obtura should be turned to maximum temperature.  Needle
   should touch canal walls, but not be firmly wedged into the canal.  Begin injecting.  Allow backpressure to back the
   obtura needle out of the canal.
4. Vertically condense with blue (size 60) Dovgan niti condenser.  Condense the gutta percha (called wadding-this is
   something that is hard to describe), switching to the black condenser after using the blue one initially.  Once the
   gutta percha is well "wadded" place, maintain firm condensing pressure on the gutta percha for 30 seconds/canal to help
   counteract the cooling shrinkage of the gutta percha.
5. Go to www.excelinendo.com if you are interested in John & Joey's hands on course which will help you master this
   technique.

Mark, do you use this technique religiously or have you hybridized it a bit.  I've got an Obtura II sitting on a shelf
because I can't get past the point of hot gutta percha/Resilon shrinking.  With Bill Watson and Fred's apical control
lesson I've learned that cold material does not shrink.  In my untrained reasoning, the more cold gutta percha/Resilon I
can put in that well gauged apex and the less ZOE/Epiphany I put there then the less the shrinkage will be and the less
leakage I'm going to allow.  If I plug the apex with a cold point and back fill will I heat that plug/fitted clipped cone
to the point it will shrink?  I am now using System A on some cases but still feel that I'm heating the Resilon at the
apex.

This is the problem I have with Barry Musikant's technique.  He's not really concerned with filling the shaped apical area
with gutta percha.  He's using the same size point on every case and slamming it home.  He's depending on cold sealer to
fill the apex and we know that shrinks...even AH 26.  We know hot gutta percha shrinks even when held under pressure.  I
can't get past the reasoning that fitting a well shaped apex with an apically sized cone and very little sealer is going
to give a better seal.  Could I use the clipped plug pushed into place with a plugger and then back fill without heating
up the plugged apex?  Any answers will be welcomed.  Guy

Guy, I don’t have all the answers for you.  I don’t know that any of these obturation techniques represent utopia.  As
much experience I have in doing resin bonding from my restorative years (only adhesive restorations for the last 5 years
of practice), I still don’t trust that I can effect a leak-proof seal in the apical third with resin bonding.  I know you
feel differently.   Have you ever treated some extracted teeth and cut them back to evaluate your obturation technique?
I’ve done it with my technique and it looks pretty good - Mark

Guy,

You simpify things a bit too much and lose some accuracy in the process. I always state that the MINIMUM preparation I
create is a 35 at the apex and an .08 mm/mm taper. The medium point that I fit (I prefer the ones from Dentsply Maillefer)
binds about 1 mm coronally to the most apical position of the preparation. You get excellent tugback consistently when you
do this. The epoxy-resin cement that we place with the bidirectional spiral followed by the generous coating of the
prefitted medium gutta percha point has been shown thru dye studies to seal the apex at least as well as any other
technique used. The gutta percha point's major function is to act as a carrier and a driver of the cement. it has no
inherent sealing abilities of its own.

One of the nice things about not doing thermoplastic techniques is you have the luxury of completely flooding the canal
and the point with cement without any concern for driving signficant amounts of cement over the apex. This is simply
because the coronal escape route for excess cement remains patent, unlike the almost immediate coronal blockage that
occurs when using any thermoplastic technique.

Another advantage is that as the cement and gutta percha warm to body temperature (from 24 degrees c to 37 degrees C) they
expand approximately 1.75%. This is not a lot. but it is headed in the right direction. Between the bidirectional spiral
and .08 mm/mm taper of the gutta percha, the cement is driven laterally with great efficiency. Since the viscosity of the
cement at room temperature is thinner than plasticized gutta percha it takes less apical pressure to drive the cement
laterally into all the nooks and crannies of the canal in the goal of achieving a 3-dimensional fill.

When canals require further widening I do notg hesitate to create wider apical preparations and at times greater tapered
preparations. In these cases i will either cut back on a medium point or place a .10 mm/mm tapered gutta percha point (a
medium large) or a .12 mm/mm tapered gutta percha point (a large).

So there is no philosophy of one size fits all, although I would say that most teeth are adequately shaped to a 35 at the
apex and an .08 mm/mm taper. Certainly with the correlation of thicker rotary Niti instruments negotiating curved canals
separating more frequently, the impetus to create these tapers with a rotary system encounters more risk than when done
with a reciprocating system that shapes 95% of the canal space with tough inexpensive stainless steel before it uses any
Niti at all. Under any circumstances we are not "slamming" that medium gutta percha home. We are placing it with care
after creating a shape that accepts it with predictable tugback.

In the next few days, I'll post 6 or so cases and you can judge for yourself, if it looks like the fills are just slammed
home. I have a huge number of cases with lateral canals filled in the most apical 2 mm of the canal too.

Regards, Barry

Haven't had to extract any yet, thank God.  Guy

What I was talking about is doing some endo on teeth you’ve had to extract due to perio or ortho, or non-restorability,
and then cut them back and look at your fills - Mark

Mark, my point was not that you were not getting good fills.  I have no question about that.  Part of the hoopla about the
new resin sealers is just how much they shrink and disintegrate.  I have no doubt at all that they do not disintegrate
because that would be a very easy thing to research.  The question is just how much they shrink on setting.  We know we
have to go to great lengths to remove all bleach before obturation and that is not a difficult thing to do with modern
canal preps but the material still shrinks on setting as does hot gutta percha.  We also know that all resins shrink on
curing whether they are self cure or light cure.

I've considering going to the Simplifills as Bruce suggests and backfilling with the Obtura but how much shrinkage does
that add to the resin mix?  Now I only have the sealer shrinking because I'm using a single well fitted cone to plug the
apex and attempting to get as little sealer as possible in that seal.

Bruce, do you think that you get a better seal with Simplifill and back filling with hot Resilon or with a well fitted
single cold cone alone with sealer/well fitted cone and lateral condensation?   You have to heat the Simplifill with the
back fill.  Guy

Guy,

I Don’t have a definitive answer on what would seal better – Simplifill/Obtura or the lateral technique. There is research
that suggests  that the Simplifill technique with an Obtura backfill may be better. Heated Resilon only shrinks about
0.5%, where the sealer shrinks about 2%. Whichever technique allows the minimization of sealer should seal better. Maybe
Dan Shalkey can comment on his experience with Simplifill with Resilon. Dan? - Bruce

Bruce, Testing with ISO standards by Gianluca Gambarini showed that Resilon sealer expanded 0.2% - Fred

Now that I like.  I'm staying with cold Resilon fitted to a gauged apex with Epiphany.  Hey, Fred, think Alvin Artz could
put paraformaldehyde in Epiphany and do Sargenti with that since it expands rather than shrinks like ZOE?  :-) Guy

I like the Simplifill with PacMac backfill, or a well fitted cone pacmaced - DanS