Screw Retained Crown on a Hybrid Titanium/Zirconia Abutment

[actittle]

First of all I'd like to say that this is theoretical, not a problem I currently have on a live case.

Hopefully someone out there has experience with this issue.

If I make a screw retained crown on a hybrid titanium/zirconia abutment is there any way to remove the titanium connector if I need to add a contact or make some other corrective add-on?

 

[rkm rdt]

All ceramic work is completed prior to cementing to the titanium interface.If you need to add on to the ceramic you will first have to burnout the cement and remove the titanium .

 

[rkm rdt]

...not that I have had to do that!...

 

[JohnWilson]

RKM nailed it, when we do this type of restoration if the contacts look a bit funny on the master model I will not cement the base in. We will let the Dr do it after he verifies the contacts/contour/shade/occ.

Makes way more sense, running up the crown to burn the cement out is not something I like to do, it can potentially fracture the interface and degrade the machine fit of the interface.

What we do is screw on an analog, we submerse the restoration in acetone and soften the cement, we then grasp the analog with channel locks and pull. When the insert come out it usually has the cement attached to the ti base and while the interface to the fixture is protected inside the analog we sand blast the interface to the crown. We do our modifications to the crown then we cement the insert.

So like I said after doing this a few times its much more desirable to have the Dr do it after tryin.

Just use your head when it comes to using solvents in the lab,

 

[French Cadman]

Hi John !

What is the best cement ( model,mark ) for zircon/titan base ?

Thank !

 

[k2 Ceramic Studio]

Hi John !

What is the best cement for zircon/titan base ?

Thank !

Hi Cadman I know you were asking John but we use Ivoclar metal/Zr primer then we use 3M ESPE RelyX uNICEM 2 ( THE ONE WITH THE YELLOW TOP)

 

[JohnWilson]

We use GC metal primer and RelyX

 

[French Cadman]

Thank you my friends, I don't know this primer !

I'll try it as soon as I can ....

Thanks !

 

[Nano]

Hi all

I use 3M Relyx for definitive cementation and we are happy with the results but i have used about ten sysems for temporary cementation (for testing in clinic) and always they come back loose.
Please, have you any trick for temporary cementation between Ti interface and Zirconia crown?

Wax No
Light fast silicone No

 

[[email protected]]

I just purchased the Ivoclar "abutment solution kit" used for same system of making an implant except with emax as opposed to zir. The cement used is called multilink implant cement and you have a primer called monobond. The kit comes with a "try in" luting material with the idea being that you don't cement to the ti base until you have done a try in if you want to. I haven't done any yet as just getting all the bits and bobs together. Has anyone used this stuff before and if so has anyone had to separate after luting, i.e. in the event that you opt not to go with the try in cement, can't see Johns solution working with this as how does the acetone penetrate into the cement ? Confused.

 

[JeffT]

Hi Keith, I have cemented 4 emax hybrids with the Multilink now and have had one come back for adjustment so just burned out at 600.c no probs. I have only used the trial sized kit which does not come with try-in material.

jeff

 

[[email protected]]

Hi Jeff, so you just put in a furnace for say 5 mins at 600 deg Celsius and that burns the cement destroying the bond, you then separate the ti abutment from the crown, adjust crown, clean up the ti abutment with glass bead blast? And then re cement. Is that what you did? Ps thanks for the help, just helps to know these things before the problem could arise.

 

[.:FIN:.]

Most of the ti-bases are grade 5 titanium (Ti6Al4V) which have better strength than pure titanium and it also tolerate more heat without loosing its features. Although grade 5 titanium will loose its strength after temperature will rise over 550C. So to be sure not to damage the features of ti-base, its better to keep temperature under 500C. With Multilink I have noticed that something between 450-500C is enough to burn the cement of.

 

[JohnWilson]

How are you shining the interface after you run it up in the oven?

 

[JeffT]

Hi Keith, yes I just placed it in my porc furnace and put the muffle up for a minute on standby. I would def drop heat to 500.c maybe even 400.c if that does the job as Fin said. And I just did the steps you mentioned and re-cemented to base and polish the interface as John suggested. I think a try-in is def the way to go but my dentists don't want the hassle of another appointment I guess. So I triple check contacts ect. and then check them again

 

[hammerhead]

For all of you with debonding issues or John having sleepless nights,try rocatec on abutment and tit base shot at 3 bar .Yet to have anything come apart in 4 yrs.U are geting sleepy John VERY sleepy

 

[Nano]

Can I change "try-in" material by ?

 

[rkm rdt]

How are you shining the interface after you run it up in the oven?

A soft brass handpiece bristle brush will remove the discoloration without scratching the interface.

 

[JohnWilson]

A soft brass handpiece bristle brush will remove the discoloration without scratching the interface.

I have some of the fine stainless brushes I have not seen brass.

thanks for the tip,

 

[rkm rdt]

I have some of the fine stainless brushes I have not seen brass.

thanks for the tip,

Stainless steel is just as good however the brass ones give you that gold/brass anodized colour.