Fractured izir bridge

[prestige.dental]

Many many hours of work
, placed in Ivoclar oven overnight and found this in the morning ..... A fractured bridge, $300 puck down the drain.....

I have successfully done one izir bridge recently that you can see on the side.

Can somebody give some words of wisdom.

Thanks

Sam

 

[Marcusthegladiator CDT]

Your most distal sprue looks good, the rest are so thin. Beef em up and maybe add 8 not 6. Go for the gusto.

 

[Gabriel]

Did you dry the framework before sintering it? Something like this happened to me when I fired up a bridge without drying it first. The material is very thick in such frameworks and instead of allowing the framework to warp the sintering support and the thick material won't give in and the result is this. Make sure you dry it very well before sintering, maybe keep it two times as much as you would keep a regular framework to make sure all the moisture within has gone.

 

[CoolHandLuke]

if this is a fracture (shear) while sintering then you have an area where one of two things happened: either 1. during milling or sprue trimming there was some vibration in that area that opened a crack. or 2. one side of the bridge was not properly supported.

by the photo above i'd echo the previous statement - use LARGER diameter connector sprues and use more.

 

[prestige.dental]

Thank u guys for the help and support you guys provide. Thank u for not letting me feel lost.

 

[grantoz]

how long was your sintering program what was you temp rise and fall.did you dry it completely before firing. was it cracked before you sintered.these are the main reasons large zi bridges fail.Also good quality pucks are essential no knock offs

 

[DMC]

too wet still

 

[CatamountRob]

too wet still

Scott!

 

[2thm8kr]

Scott!

Someone hacked his account. I think it was Terry.

 

[CatamountRob]

Someone hacked his account. I think it was Terry.

You might be right.
The real Scotty would have written, "too wet still?".

 

[2thm8kr]

You might be right.
The real Scotty would have written, "too wet still?".

The Australian accent was the give away.

 

[Doris A]

too wet still

You've been missed!

 

[CoolHandLuke]

with every bullet so far

 

[Doris A]

I didn't say by who...

 

[ceram1]

The real house wives of DLN

 

[JohnWilson]

I bet the fracture was there after milling and you missed it. I would also check the circumference of the nearest fixture and check thickness around it. By chance is the nearest fixture very divergent? When we do the strategies we set the cam not to go into the holes as it's doing the fine milling and do a separate for each holes slowing down feed rate and rpms. The ones I have had fracture were 100% my fault.

 

[dmonwaxa]

I bet the fracture was there after milling and you missed it. I would also check the circumference of the nearest fixture and check thickness around it. By chance is the nearest fixture very divergent? When we do the strategies we set the cam not to go into the holes as it's doing the fine milling and do a separate for each holes slowing down feed rate and rpms. The ones I have had fracture were 100% my fault.

John what would you recommend the minimum thickness of the Zr wall receiving the Ti inserts? Maybe others can feel free to chime in also.

 

[Marcusthegladiator CDT]

You might be right.
The real Scotty would have written, "too wet still?".

Or, "it's too wet idiot."



Sent from my iPhone using Tapatalk

 

[JohnWilson]

It's not so much the thickness at the base of the ti but it's relation to the screw channel. Lots of times we are so used to looking at joint thickness interproximally but it's the demension buccle ling that often is missed. Your 2d cross section tool is your best friend here.

 

[2thm8kr]

It's not so much the thickness at the base of the ti but it's relation to the screw channel. Lots of times we are so used to looking at joint thickness interproximally but it's the demension buccle ling that often is missed. Your 2d cross section tool is your best friend here.

That rule of thumb is not only for Zr, but Ti as well. I've redone 2 full arches done on Ti by other labs that failed in similar fashion. One had lingual set screws.