attachment case

[CShof]

I'm not the most knowledgeable person when it comes to attachments. I received this case today. Patient already has a bridge with attachments so the doc inserted these plastic things and took an impression and I'm not so sure this is going to work. They don't exactly remove from the model so I'm thinking if the casting company waxes to them that they will break the model when they're done. What do I need to do this right? Do I need the actual bridge?
FYI - #21 will be extracted

 

[kcdt]

Does the male piece slide in and out of the female accurately?
If you're uncertain, fabricate the framework and the males separately, pick the males up intraorally and weld/ solder them on. You'll probably have to anyway.

 

[CShof]

I don't know if they slide in and out accurately or not, they are a piece of the model at this point. Can they make the males with the model I've got here? So you're saying make them separate then get an impression with the frame and males in place and attach them together at that point? That sounds like a good plan. Only one problem, its an immediate and I'm thinking they want it to be finished before extractions. I dont think that's going to be possible, I think I'm going to have to ask them to do extractions then take new impressions at that point.

Please humor me and let me write this out.
Step 1 - Have frame and male attachments made
Step 2 - Extract teeth
Step 3 - Try in frame and attachments and get pick up impression
Step 4 - Solder attachments to frame
Step 5 - Bite rim, set teeth, normal deal from there.

One question, how do I save the model after they pick up the attachments and I solder them to the frame? Won't the female area break apart since it will only be made of stone? Is it possible to coat the males with something so they will slide out?

 

[tomvou]

In my opinion,doctor have to know the attachment's company and kind.I mean companies have a variety of matrix or patrix analogs that doctor put them in the mouth and then takes the impression.
Then in this impression you put the laboratory analog before you pure it with super hard gyps.
After pouring the impression with super hard gyps,you take a master model,that in the area of female has the lab analog,that it is made from alloy ,I think is a kind of Cu.So you can work without the danger of breaking the critical area when you are going to check the fitting.
You can have help from ZL-Microdent-Attachment GmbH & Co. KG .

 

[nvarras]

These are semi-precision attachments (plastic) so there are no analogs. You can only use new males. Even if there was an analog I don't think it would work well. This was a part of an RPD and the old males were probably cast as part of the frame (chrome). The females were cast out of a c+b alloy which is softer than chrome therefore your females will have worn to the point that the new males will need to be customized to fit. Make sure that the impression of the females is accurate and goes all the way down to the bottom of the females. Find the path of insertion that is parallel to both attachments; put the male in the surveyor and slowly add wax to it while you are moving it in and out of the female. Then do like Kcdt recommends and cast them separately and pick it up. It looks like there is enough space distal to the canine so the chrome lab remove #21 and wax the struts for the males. The patient is still going to have to go without the partial for a few days until you can solder the attachments and finish the partial.

 

[CShof]

So I need a new impression without the males inserted in the bridge attachments? Then cast something to fit that impression? This impression was taken with the plastic males in place in the female bridge attachments. I poured it up like that and the plastic males are pretty well stuck where they are.

I don't have the equipment to cast anything myself so I'll be outsourcing that job. I'm going to guess the doctor will probably say the plastic males fit fine and to use those. In case doc says to use what I've got, can the casting company make the males with what I have or do I still need a new impression? It would almost be easier if I could have the whole bridge.

 

[nvarras]

If the doctor says the males fit well AND you trust him...then move forward with what you have but someone is going to need to get those males out of there without damaging the model.

 

[CShof]

Thank you everybody for you advice, I really appreciate it. One more question. If I get a new impression that accurately depicts the females, why can I not have the males cast as part of the frame? What are the advantages to having them cast separate?

 

[droberts]

Thank you everybody for you advice, I really appreciate it. One more question. If I get a new impression that accurately depicts the females, why can I not have the males cast as part of the frame? What are the advantages to having them cast separate?

You could...But minimal warpage in the frame will not make an accurate fit. My experience, best to have them cast separate, then laser welded or soldered to frame.

 

[CShof]

Since there seems to be an overwhelming consensus that they should be cast separate, I will definitely take advantage of the experience of this forum and go that route. Please humor me with one more question.

Say I get my new impression and have the males and frame made on that model. Then I get the males picked up in a new impression so I can attach them to the frame. After attaching the males, that pick up impression model will be destroyed correct? Will the frame fit back onto my original model for setting teeth and processing?

 

[AJEL]

The piece looks a little like the Sterns 070 or GL, I still have some of the pieces in old stock. I put the male & analogue on the second instruction page. Click on the image & U will go to photobucket with severalpages on this type intraoral attachment. The idea was to direct forces along the center of the tooth with the hope of reducing the tilting forces. It was thought that Cekas & distal extension attachments of the time were working like an ortho device moving the crown & contributing to tooth failure (they didn't take into accord the heavy smoking of the 60's - 80's0's). So these intra oral attachments very difficult to do & hader clips, ASC52, Dalbo, & the old Zest anchor were produced. Of which I still have some parts for)

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[kcdt]

Since there seems to be an overwhelming consensus that they should be cast separate, I will definitely take advantage of the experience of this forum and go that route. Please humor me with one more question.

Say I get my new impression and have the males and frame made on that model. Then I get the males picked up in a new impression so I can attach them to the frame. After attaching the males, that pick up impression model will be destroyed correct? Will the frame fit back onto my original model for setting teeth and processing?

You could attach plastic females and pour your pick up like that. Or you engage in selective destruction of just the keyways and use the rests and bead marks to seat the frame on it.