From: Marga Ree
To: ROOTS
Sent: Tuesday, October 02, 2007 1:08 AM
Subject: [roots] Benefits of pre-endo BU

Hi all,

Here is a case that I finished last week, it shows the benefits of a pre-endo BU.
It's so easy to do this in the first session, in my opinion there are only benefits, e.g.
1. Large reservoir for irrigation solution
2. Better esthetics, patient comfort
3. Better seal between visits
4. Easier to plan the time needed for the sec appointment

In this case, there were subgingival margins. This may cause problems when trying to obtain a dry working field.
This is how I deal with subg. margins. Whenever I treat a severely broken down tooth,
I always clamp the adjacent teeth, that gives me more overview.

1. Removal of old filling material
2. Evaluation of margins
3. Gingivectomy by using an electrosurge
4. Packing cord and leaving it in place for a few minutes. Sometimes this is enough. If not then I'll proceed with
5. A material that is called Expasyl, which contains aluminum chloride, and gives an excellent hemostasis.
   I leave this 5 minutes in place
6. Removal of expasyl and cord, inspection of margins
7. Application of a matrix, in this case a used an upside down core form by Kuraray from which I removed the top
8. Insertion of canal projectors
9. Conditioning of dentin and enamel. Let me go a bit in detail on the procedure.

As for the products, the 4th generation bonding agents are still the gold standard. So I typically use 3 separate
products for acid-etching, priming and bonding, and I want my bonding agent to be dual cure.
Since I use self-cure and dual-cure core materials, I use primer and bonding that can be used in conjunction with both
core materials (so not too acidic). It's called Clearfil SA primer (not to be confused with SE primer, which is a self
etching primer) and Clearfil Photobond dual cure bonding agent from Kuraray.

10. Then put the core material in a needle tube from Centrix.  A core materials that is suitable to be used in a needle
tube is e.g. LuxaCore by DMG, you can use this also to cement a post, it has the right flow. Other core materials with
a similar consistency are ParaCore by Whaledent, and Build-it by Pentron.

11. After the material has set, remove the canal projectors by screwing in a hedstrom file.
12 Remove the matrix
13. Finish the BU, and enlarge the access opening by connecting the holes formed by the canal projectors
14. Do a final irrigation, dry the canals, and apply Ca(OH)2, fill the access with cavit
15. Remove the rubber dam and adjust the occlusion.

I don't mind if there is no contact point, this will be taken care of in a later stage.

In the second session, you're only have to fill the canals, stick in the post, and close the access opening.

Endo is easy.....sometimes....:-) - Marga








Fabulous teaching cases! - Siju

What type of Matrix did you use Marga?..it looks like plastic.- Joey D

It not only looks like pastic, it is plastic...:-),
it's a Kuraray core form with the top cut off, and used upside down.- Marga

Since you use them...I presume you like them.
Do you have a part number for the forms? - Joey D

http://www.kuraraydental.com/accessories.php
Core form kit (# 970) - Marga

Premier makes some conical core forms that work well for this purpose, and pentron also has some core forms
you can cut the top off of that also works very well. - gary



Excellent lecture of how to do the build-up, Marga.
Do you use the split-dam also in the lower arch? Is it possible to avoid saliva coming "through" ? In my hands it doesn't work very well.
Do you use heavy or xtra-heavy rubberdam? - Jörg

I subscribe to dr. Siju's post. TEN times.

thanks to Roots,now I am practicing  to use Centrix Needle Tube to
place Build-it for core BU.
my question is regarding their compatibility with Build-it. I find it
sometimes too viscous and some of the load remains in the Tube.

I read on http://www.cjmengineering.com/index.html in the Projectors technique section
that they recommend thinning the composite core materials with a
thinning composite agent because most of them are too viscous when
used with the Centrix Needle Tube. Should I use a composite thinning
agent when I use Build-it with Centrix Needle Tube , and If yes, can
you recommend me one?
or simply this is not the case with Build-up(which i suppose), and I
am not storing well the material to have the right flow for placement
(or simply I am at the bottom of the learning curve)

also which delivery device is better to use when placing core
materials for better control, the gun or the syringe ? I have only the
syringe but I can buy also the gun, so that's why I ask - Cosmin