Combo cases on a SAM3 articulator

[wwcanoer]

So this is my first question for this group, I hope you can help me.

When you have a combination case of implants and crowns that is to be mounted with a face bow on a SAM 3 articulator and you want to use with magnetic mounting rings, how do you go about it?

In the first photograph, My sectioned model, first pour, was used for margin definition for the crowns. But the model, with base, was too thick to probably bring the top of the articulator into contact with the mounting jig.

Second photograph. So I mounted a solid model, second pour, on the SAM.

When I went to recheck contacts, etc., on my sectioned model, I discovered that I now had an open contact between implants on #9 and #10 (these had not been sectioned) and that #9 was now slightly longer than #8. To me, this meant that something had shifted somewhat on the second pour.

So aside from getting another gray hair to add to my collection... There has to be an easy answer to this, but I'm not seeing it.

What is everybody else doing in this kind of situation?

Thanks in advanced,

Carol

 

[JohnWilson]

Face bow mountings can be a real pain, especially if the Dr has not adjusted the table/fork correctly. Some times when the jig gets mounted to the articulator there is not enough room for a pinned model (like you have). When this happens its generally because the client has not adjusted the fork correctly in the jig. When its a local doc I run it by and show them and then its a non issue in the future.

Another option is to mount the Solid as you have done. Make a custom incisal guide table and then cross mount the pinned model. We routinely do this when implants are involved so that we can have solid model that has the analogs in it as well. We do all the movements/check contacts on the solid model and stack and grind in on the pinned models.

 

[Al.]

What is everybody else doing in this kind of situation?



Carol

Use a different magnetic system that is shorter or not use one at all if there isnt room.
I used to pindex my base and use those plastic reverse pins to make mine removable. Now the system I use has a really short magnetic base.

Ive never used that art before. Is the incisal guidence pin supposed to be attached to mand. like you have it?

 

[zena]

get different skinnier mounting plates or trim some of the base off your cut model to make it fit on the articulator.

 

[TheLabGuy]

Wow, that's a lot of stone (i.e. expansion and chance for distortion). I use to use Sams articulator all the time, never used them with the magnetic base......I now use Stratos .....much better.

 

[JohnWilson]

Wow, that's a lot of stone (i.e. expansion and chance for distortion). I use to use Sams articulator all the time, never used them with the magnetic base......I now use Stratos .....much better.

Sam was never my favorite either now my new all time favorite is the panadent.

 

[wwcanoer]

Rob,

You're right, that is a lot of stone to be working around, and definitely can cause issues. So what I did, was grind the model down until I hit the analogs, then went ahead with my pinning and basing. So maybe I should've just continued grinding away until I had a proper thickness, and not worry about the analogs.

Al,

Yes, the incisal pin is supposed to be that way.

And, I have found thinner mounting rings that are on order...

Thanks for everybody's input,

Carol

 

[TheLabGuy]

One last thing Carol, I know combo cases are combo cases, but when you have that much removable and fixed in one case (i.e. all that stone)....what if you break it up. For instance, tell the Doctor you'd like to seat the crowns and then get an accurate bite before doing the partials. I'm not a big fan of combo cases, just my opinion, much easier to take everything in steps. Maybe i'm being retarded, let me know if I am......wouldn't be the first time.

 

[CShof]

tell the Doctor you'd like to seat the partials and then get an accurate bite before doing the crowns.

Do you find it easier to do a partial first then make the crowns fit the partial later? Coming from a removable background I'd rather make a partial to fit existing crowns, but then again I don't make crowns either. If it were broken down into steps, what's everybody's preference, partials or crowns first, and why?

 

[yooper886]

Either way the team decides to do it you should always have a removable tech set the denture teeth in set in place so it aids the c&b tech in the fabrication of the crowns, this can also provide an aid to the partial tech in the fabrication of the frame. If possible the c&b team member should know the design of the partial framework. The more information you can pass along to all the team members involved the better the product is going to be in the end not to mention less bitching among ourselves wondering why the other team member did this or that.

I kept mentioning team because there is at least 4-5 techs and dentists working on a case like this.

 

[TheLabGuy]

Do you find it easier to do a partial first then make the crowns fit the partial later?

Easier to do the fixed (crowns) first, get your rests put in the crowns and get those seated, then get an impression for the partials......that would be the ideal way to do it.

 

[Al.]

Easier to do the fixed (crowns) first, get your rests put in the crowns and get those seated, then get an impression for the partials......that would be the ideal way to do it.

I agree 100%. Its a pain in the butt to make crns fit to exhisting ptrs. and I wouldnt trust doing it all together.

 

[zena]

when DR wants everything at once, at my work when we get combo cases that need crowns and partial, we do the crowns first then when they are done pass finished crowns to the casting department for the partial part. I don't mind doing it the other way where crowns are done last.

 

[wwcanoer]

So this is basically how this case progressed
appointment 1: study models for diagnostic wax up
appt 2:impression for lower partial framework.
appt 3: try in framework, prep upper arch, impression of prepped teeth and of implants.

After I got everything mounted, do a full upper arch wax up, sit the teeth on the lower partial, I then got to work on the crowns. The implants were a challenge, as they all require either 15 or 20° abutment's, but everything pulled together very nicely. We cemented the case today, and the patient had very sore smile muscles! Took a new upper impression and bite, and will be sending the partial off to be finished.

One of the big advantages of being an in-house technician, is that I get to see these big cases from start to finish. But one of the disadvantages of being in-house, is that when something doesn't go smoothly, as with what started this thread, I don't have somebody immediately to bounce a question off.

This is\was my first "mega-combo" case. New lower partial to correct occlusal plain , full upper arch reconstruction with implants and porcelain crowns. I think I'll kick back and relax this weekend!

Thanks again to everybody

Carol

 

[TheLabGuy]

Glad everything worked out for you Carol........take a break, you earned it!!!!!!!