Six implant-direct bar thingys...?

[DMC]

Whatever you call this 3.0mm Implant Direct thing, we are making a bar on Six of them for someone, somewhere..... Kinda looks like a Multi-Unit top, but without the tapered walls.

This is included in the DDG CAD library for DentalWings, 3shape, and exocad .

First we try the prototype.....maybe is good? I dunno?

Tight verticle!! My Distal extensions are 12.0mm past last implant.

I am sure the next lab will push that back a wee-bit with plastic.

Any thoughts?? Too weak? It is almost 4mm wide, hard to tell.

 

[dmonwaxa]

Scott is this for a Hader Bar "clip-Denture", detatchable; or is the acrylic being processed directly to the bar, ie: "wrap around", screw retained?

 

[doug]

What's the torque spec for those things?

 

[droberts]

IMO, a better design in relation to the tooth set-up would be a Montreal style metal lingual.
That is if the screw access hole is low enough to allow a lingual flare of the metal bar to the
lingual of the anteriors. Not a good choice of implant for this type of case. On all hybrid
cases, I prefer to have the implant 2-3mm subgingival to allow room the bar height. A
platform as above, limits this...

 

[dmonwaxa]

droberts, agreed on yhe lingual flare. I personally don't like the anterior cantilever, implants are way lingual but that's where the bone is. I would also consider a design that extends the metal on the tissue and at least lingual to the anterior setup and include mechanical retention and reinforcement in the form of posts to accommodate the teeth. Thoughts?

 

[DMC]

The Top of Screws will be flush with the top of metal screw channel.

Cannot go lower around the screws with the metal. (Top of chimney)

Yes, the teeth at quite anterior to the implants.

I dunno what to change?

Yes, customer wanted complete wrap, but some places are only 3.5mm thick from tissue to top of wax-up.

No room for the retention pins. I have many design in cad and pins are only One click away.

Teeth are pretty much on the bar as it is!

Customer did not want metal showing on bottom, but I bet we end up doing just that.

 

[DMC]

What's the torque spec for those things?

Don't know? If cutomer asks, I tell them PLEASE ask the manufacture, not me.

I have too much in my head to try and keep up with torq specs on all things.

I think we are using Nizzznick's Second from left part? TheScrewIndirect?

Have you seen the new GoScrewYourself System yet? All-in-One?

 

[DMC]

Southern Style Retention Pins?? LOL

You guys ever do this?

Is this stupid, or what? I am 3d printing today to see what it looks like in real life....

Scott

 

[DMC]

This is what we are prototyping today.

??

I called it Southern Pin-Retention, unless there is already a name for this?

 

[droberts]

Not sure what the intaglio surface of your bar looks like for the metal / acrylic
finish line? It looks as though the bottom lingual of your bar is touching the tissue?
IMO, that can be a hygiene issue.

 

[DMC]

 

[DMC]

The customer liked the 1st wrap-around better.

Also mentioned the food trap thing....

I think we go back to wrap around with some little retention pins added at horizontal angle-to-5 degrees?

 

[DMC]

For C&B....we all make bridges and pontics just like this all day long.

Why is it acceptable for that, and not for a bar??

I am talking about Sadle the ridge on buccal/labial and ending just at crest of ridge.

We hang down material right on the tissue, all the way up to the crest. ??

Food trap...OK Yes. Looks good...YES. Ask patient which they prefer and it is 99.9% in favor of cosmetics.

Do you guys design each and every bar off the ridge, and also the resin is off the ridge? Just a gaping space?

How much space? (Minimum)

I just don't think this case has enough room, for this.

 

[DMC]

Did you guys know you can design you own bar-profile in .obj or .stl and import into exocad?

We tried this last week. Worked great, after we failed by having profile shape orientation facing wrong way in the cartasian system.

Figures it would be the Third time around we got it right...Centered a curve around 0,0,0, and we extruded the curve up 1mm to give it some 3d-walls...left ends open (just a guess and it worked)

Keep rotating until you find the magic orientation.

You can draw a profile of anything it seems.

Does anyone know the proper rules for importing a bar profile into exocad?

How can I make a .bar file with corrosponding "handles" to tug the bar around and strech?

Mine, I could only strech in the Z-axis, by pulling the bottom of new profile downwards.

The bar in pics above I just designed free-hand in a few minutes using exocad's wax tools.

 

[droberts]

Scott, it sounds as though you are going with the original full wrap around. The other design,
I would not recommend placing the metal/acrylic finish line directly on the ridge. Move it to the
labial/buccal. Having a seam on the tissue as such, is a definite hygiene problem. The doctor
is the only one that can remove this, it could look real ugly after 3-6 months. As for touching the
tissue with the metal bar, or acrylic. That is left up to the customer. I normally on the mand. try
to leave a 2mm space, or what is ask by the doctor. As where the max. I close off to avoid
food/saliva flowing over the anterior.

 

[martintay]

I still think a bit more "Acrylic-Retention" on the bar ? But its looking good ! Consider "Pontic-Scoreing" in the acrylic adjacent to implants for "Super-Flossing" maybe ??

 

[DMC]

So, Two materials butt-up together at the ridge.

How does that produce a food trap anymore than if it was just One material??

You think a human cannot get a smooth finish line?

You think there will be a gap or void, or what exactly?

 

[martintay]

We "Pontic -Score " ceramics as well !

 

[droberts]

The bar above is mainly relying on mechanical retention, not chemical. Putting the seam at the
center of the ridge? Over time, that can create seepage between the acrylic and metal.
From the design above of wanting metal on the ridge, there is no reason you couldnt
extend the base to the labial / buccal. This is not the best analogy, but you never see a boat
company put a seam at the bottom. Fix the problem before you may create one.

 

[DMC]

Yes, I took Dental materials in college. I understand Ti does not chemically bond to resin.
Thanks. (??)
Bottom of a bar does not get forces applied directly to it, unlike the bottom of a boat.
Terrible analogy. LOL Not even close to same situation. Totally opposite.



The Two material need to join somewhere.
Why does it matter if it is on top of ridge, or a few millimeters away/in front of it?

Same/same. ??

Nobody is chewing on the underside of a bar. ??