Debonding of Multilink Hybrid cement from abutment

[rkm rdt]

Hi folks,

I've been having trouble with this case. The cement keeps debonding from the zirconia.
You can see the one abutment has a different resin cement so it's not the cement.

I must have an issue with the zir surface. Contamination of some sort.

can you suggest a remedy that will ensure good adhesion? I sandblast and cement both surfaces. Ti bases and custom abutments have always worked but this one came apart when the dr torqued it down.

Is there a bonding agent that I could use? Have at me ! I can take it.

 

[zero_zero]

Did you cut retention grooves in the Zr structure and the abutments ? You gonna need all the mechanical keying you could get with those short parts. Try DTK-Kleber from Bredent, it never failed me...

 

[rkm rdt]

There's not a lot of zir material around those abutment except for the buccal walls. I could create some dimples with a highspeed.

 

[Patrick Coon]

Are you using the Monobond Plus on the Ti and the Zirconia? This will help with the actual bond to the Zirconia.

Your abutments are also very short. We have found for the best bond you need a height of at least 4mm on the Ti.

 

[rkm rdt]

Are you using the Monobond Plus on the Ti and the Zirconia? This will help with the actual bond to the Zirconia.

Your abutments are also very short. We have found for the best bond you need a height of at least 4mm on the Ti.

Thanks Patrick, I will order the monobond plus today.

They are short on the linguals but over 4mm at the buccal. It was a tough lingual contour to keep low and the placement didn't help.

All abutments are engaging.

 

[zero_zero]

There's not a lot of zir material around those abutment except for the buccal walls. I could create some dimples with a highspeed.

A PFM might be a better candidate?

Post a pic of the Zr as well.

 

[BobCDT]

There is clearly not enough retention form in the abutments. That said, if the interocclusal space has limited the abutment height to what is in the photo the case should be screw retained , likely directly to the implants.

 

[rkm rdt]

A PFM might be a better candidate?

Post a pic of the Zr as well.

That is my plan B .

There is clearly not enough retention form in the abutments. That said, if the interocclusal space has limited the abutment height to what is in the photo the case should be screw retained , likely directly to the implants.

The picture is a bit deceiving as these abutments are lingual to the ridge and bevelled . This is a screw retained md zir bridge.

Now that I look at it ,the abutments are not placed in the right order by the dr.

 

[rkm rdt]

I'll follow up with more pics later.

 

[PearlZ]

That is my plan B .


The picture is a bit deceiving as these abutments are lingual to the ridge and bevelled . This is a screw retained md zir bridge.

Now that I look at it ,the abutments are not placed in the right order by the dr.

HAAA HAA HAA OMG is this the same guy that called your bite wonky ?

 

[JohnWilson]

Any bonding agent that has a cursory bonding improvement to ZI will not bail your ass out on this case. In never hurts but its not what is causing the failure here

Mechanical retention is the only thing you have a chance with, however if I was a betting man if this case is splinted together the master model may be off a bit and when the Dr torques them in the interface is now under stress and it debonds. Even singles that have thick and fiberous tissue and you are blanching the case heavy I have seen this.

Was there a mock done and verified or a jig made? If so ask the dr for the xray, it may open your eyse to the problem.

I have outlined our protocol to cement on this forum before but one thing I always like to refresh is after you cement let the case set do not go and try the soft tissue on the model and screw things back on. Outside the mouth this stuff takes much longer to self cure and sometimes the initial tack light cure does not fully penetrate and gives us a false sense that its ready to go.

 

[PearlZ]

also why wasnt this case done on your trios ?

 

[rkm rdt]

Any bonding agent that has a cursory bonding improvement to ZI will not bail your ass out on this case. In never hurts but its not what is causing the failure here

Mechanical retention is the only thing you have a chance with, however if I was a betting man if this case is splinted together the master model may be off a bit and when the Dr torques them in the interface is now under stress and it debonds. Even singles that have thick and fiberous tissue and you are blanching the case heavy I have seen this.

Was there a mock done and verified or a jig made? If so ask the dr for the xray, it may open your eyse to the problem.

I have outlined our protocol to cement on this forum before but one thing I always like to refresh is after you cement let the case set do not go and try the soft tissue on the model and screw things back on. Outside the mouth this stuff takes much longer to self cure and sometimes the initial tack light cure does not fully penetrate and gives us a false sense that its ready to go.

We made a temp bridge with metal abutments from his old partial.

The debonding was necessary anyway because we need to add more tissue porcelain.
Using a new model,I see a heavy contact with the premolar which wasn't there before.That could be all it took because of the short abutments.
Monobond Plus is on it's way and I will add more retention to the buccal walls of the zir. The abutments have machined grooves which are visible after the cement was removed.

 

[rkm rdt]

HAAA HAA HAA OMG is this the same guy that called your bite wonky ?

No , he is on his way out.

This is what I love about digital. Instead of dropping a client, you just delete them.

 

[lcmlabforum]

Just like the SIMS/Farmville?
Not like I played this before

LCM

 

[lcmlabforum]

I like what John said - very likely not passive clinically.
And if that was the case, doing it UCLA may introduce a whole set of problems
at the time of seating . . . unless you don't worry about seating passively, and
that sort of thing . . .
LCM