Wiggly crowns on abutments

[RileyS]

I have one dr who, compared to my other clients, is extremely picky and always has issues. Either all the other clients are really crappy and don't care what the crown is like and just make it work or I ONLY screw up on this special dr's work cause I do everyone's stuff the same.
Anyways, he always says that the crowns on Ti abutments are wiggly. I always check to see how wiggly they are and rarely find anything. I've got the design parameters set as tight as will fit with only one or two adjustments I seat them. I try to get a good shape to abutments for retention. We haven't had any cemented crowns pop off in the last 3 years.
Anyone want to give any thoughts on "wiggly abutment crowns?"

 

[desertfox384]

Some guys are always looking for an issue, and when you look hard enough you'll always find something....

 

[rkm rdt]

I have one dr who, compared to my other clients, is extremely picky and always has issues. Either all the other clients are really crappy and don't care what the crown is like and just make it work or I ONLY screw up on this special dr's work cause I do everyone's stuff the same.
Anyways, he always says that the crowns on Ti abutments are wiggly. I always check to see how wiggly they are and rarely find anything. I've got the design parameters set as tight as will fit with only one or two adjustments I seat them. I try to get a good shape to abutments for retention. We haven't had any cemented crowns pop off in the last 3 years.
Anyone want to give any thoughts on "wiggly abutment crowns?"

Are you giving him a solid model or do you section the implant die?

You could broaden the contacts which would dewiggle the crown during cementation.

However the best solution is to switch him over to screw retained implant crowns.

 

[JohnWilson]

How about a bit more info on what product and how you are fabricating it

Are they Ti abutments and Zirc crowns?

Are you Designing the abutment and crown from 2 different scans or as a split file?

 

[zero_zero]

 

[rkm rdt]

How about a bit more info on what product and how you are fabricating it

Are they Ti abutments and Zirc crowns?

Are you Designing the abutment and crown from 2 different scans or as a split file?

That's not how we play the wiggly crown game John.

 

[JohnWilson]

That's not how we play the wiggly crown game John.

I'd like to reply with some comical quip but at this moment my brain hurts from deciphering your reply so I will just say

WTF are you saying?

 

[2thm8kr]

I think he's talking about wiggling his crown at you?

 

[JohnWilson]

Ahhh , I knew I had to drink my coffee faster,

 

[RileyS]

Are you giving him a solid model or do you section the implant die?

You could broaden the contacts which would dewiggle the crown during cementation.

However the best solution is to switch him over to screw retained implant crowns.

I don't section my implant cases. I do try to make contacts extra broad but he's checking the crown to the abutment off the model i presume.

How about a bit more info on what product and how you are fabricating it

Are they Ti abutments and Zirc crowns?

Are you Designing the abutment and crown from 2 different scans or as a split file?

I'm designing cust abutments on 3shape, milled by Argen. FZC crowns on top that I scan after receiving the new abutment.

 

[zero_zero]

Cut some anti wiggle grooves on the abutment...

 

[CatamountRob]

 

[2thm8kr]

Video from before you became a dental technician. I didn't realize you were dancer??

 

[rkm rdt]

I don't section my implant cases. I do try to make contacts extra broad but he's checking the crown to the abutment off the model i presume.




I'm designing cust abutments on 3shape, milled by Argen. FZC crowns on top that I scan after receiving the new abutment.

That's just the nature of the beast. I do exactly the same thing.

 

[CatamountRob]

Video from before you became a dental technician. I didn't realize you were dancer??

Not before, it's a side gig.

 

[2thm8kr]

Not before, it's a side gig.

Ah, they don't recognize you from the hug shack without the make up?

 

[JohnWilson]

Riley,

The design of the top cap and the radius you design will dictate the tightness because of how the drill compensation and cement spacer parameters are effected by this design

If you have drill compensation on and have very minimal spacer it can still feel loosy goosey.

If you use the 2d cross section tool and measure the radius of the top cap and plan it will can help tremendously. You can then eliminate the drill comp to keep the cam from over milling these areas which will make a much more precise fit. Your draft angle on the abutment can also be minimized and the cement spacer setting for distance to margin can be reduced as well.

I do not put anti rotation vertical grooves in but I will put a lateral ledge and radius the 90's to be ready for the final restoration. This is mostly on bicuspids anything molar like I can make very square.

I send all my ti abutments to Nobel and I split fill my crowns and have them waiting in the pan for the abutment to come in. Not sure argen is up to the task with how they are milling abutments but just a heads up.

 

[desertfox384]

I don't design many implant cases with CAD so take my opinion with a grain of salt... but especially with smaller implants I will place a vertical groove on the lingual of the abutment - but what helps the most is putting a "V" on the occlusal surface of the abutment, it creates a lot for the crown to lock into on posteriors anyway.

 

[JohnWilson]

I don't design many implant cases with CAD so take my opinion with a grain of salt... but especially with smaller implants I will place a vertical groove on the lingual of the abutment - but what helps the most is putting a "V" on the occlusal surface of the abutment, it creates a lot for the crown to lock into on posteriors anyway.

In an analog state where you are dipping and casting the coping or pressing the pattern this will produce great results. When you are machining it's how the bur cuts the pattern and how the abutment was designed and how the software works that will dictate fit.

 

[Sevan P]

A few factors come to mind. How much spray is applied to the abutment during the scanning of the abutment itself. Any anti rotation on the abutment? And cement gap.

I had the same issue until I completely dialed in my settings and design.

Here is a pic of what I try to put in all my custom abutments if the walls are thick enough and allow me to place it in the design. I made a custom attachment with a flat wall and 90 degree edge and on the other side is a flat wall and a 45 degree edge.



Then in 3Shape I have the margin gap @ 0.01 and the extra cement gap @ 0.025. Then on my VHF CAM I have the cavity set to -0.010mm All my Ti and Zr abutment crown have near zero wiggle. I also find the issue even with these setting to be the scan spray, quick check and Tinactin come on very thick as were my Scan spray from talladium is much thinner. You only need a slight layer to stop the anti glare so the camera and catch the data.

This is how I got rid of my wiggly crowns on abutments.