Etching liSi vs etching e max

[Adi]

A doctor told me today that LiSi doesn't get etched thoroughly like e max , not happy with it.
I think it has something to do with the reaction layer.

What do you think?

 

[doug]

Did you check with GC to see what their protocol is for the chairside aspect, and what an etched Lisi crown should look like?

 

[sidesh0wb0b]

A doctor told me today that LiSi doesn't get etched thoroughly like e max , not happy with it.
I think it has something to do with the reaction layer.

What do you think?

zero issues here. etching works just fine and identical to emax from everything ive seen.

 

[Affinity]

What I was told by the techs that are KOLs for GC, was that because this material is more dense, it doesn't turn frosty white like emax does when its etched. Im not sure if I believe that.. I was also told that emax shouldn't be white , that means its over-etched, although they look like that even after a few seconds of acid contact..

Does your Dr have a scanning electron microscope? How could he possibly know if its etched or not? It may NOT etch as much as emax, but ive got several veneer cases that have been in over a year without debonding.. if there were no etch, I don't think they would bond.

 

[Adi]

How could he possibly know if its etched or not?

He's comparing it to the frosty white layer he sees in e max when etched, he did use this term that you used " frosty white " : if I don't see frosty white that means it is not etched well .

 

[Adi]

Did you check with GC to see what their protocol is for the chairside aspect, and what an etched Lisi crown should look like?

didn't ask

 

[Sda36]

He's comparing it to the frosty white layer he sees in e max when etched, he did use this term that you used " frosty white " : if I don't see frosty white that means it is not etched well .

My understanding is that you should try and remove white (powder residue ) as this is a by-prodct of the etching reaction. Use alcohol and micro brush. Dr.Ed McLaren steam cleans post etching, also good but not many Dr.'s have a streamer. He reccommends a jewelry steamer, small and not that expensive.

 

[doug]

Why are you even concerned about etching other than to provide info to the doc? The lab should never etch a crown before it leaves the lab.

 

[2thm8kr]

Call me crazy. I always etched every feldspathic veneer, jacket crown and emax that has left my lab. I give instructions only to clean the intaglio with alcohol after try in. Every office uses a different product/method and are you sure the doc is even at the helm for the etching? Most docs use whatever the assistant tells them to use.

 

[Adi]

Why are you even concerned about etching other than to provide info to the doc? The lab should never etch a crown before it leaves the lab.

The concern is to answer the question : is e max better than LiSi because it can be etched better , thus it will last longer without debonding ?

 

[Willard]

I was thinking GC LI press was 40second etch and e max was 20 seconds ???
Not sure

 

[Patrick Coon]

What I was told by the techs that are KOLs for GC, was that because this material is more dense, it doesn't turn frosty white like emax does when its etched. Im not sure if I believe that.. I was also told that emax shouldn't be white , that means its over-etched, although they look like that even after a few seconds of acid contact..

Does your Dr have a scanning electron microscope? How could he possibly know if its etched or not? It may NOT etch as much as emax, but ive got several veneer cases that have been in over a year without debonding.. if there were no etch, I don't think they would bond.

With a 4.5-5% HF etch for 20 seconds on e.max (and I would assume with LiSi Press as well),you should not see an etch pattern with the naked eye (especially when compared to a higher glass content ceramic like Empress)as it is only 30% glass (versus the ~60% glass of Empress). If your using a higher acid percentage like 9% HF (usually the yellow ones) then 20 seconds will be very much over etched and cutting the time in half is not the answer, as it is not a direct correlation between doubling the strength and halving the time.

 

[Affinity]

Talk to GC and have them send you some pics of their SEM images of the material when its etched, Im sure they have that.

I always etch every crown, even if its not being bonded. IMO its impossible to etch emax for under 10 seconds without getting the white haze. if thats a problem, then every crown Ive ever done has been over etched. Im not sure what else you do other than dilute it more or leave it on for a few seconds..

LiSi is nice but im not sure its comparative to emax, color-wise its better, strength-wise Im not sure, Ive had some issues.. Im not even really seeing hardly any all ceramic crowns anymore, everything is done in zr except for veneers.. that is a trend I just noticed this year...

 

[Patrick Coon]

Talk to GC and have them send you some pics of their SEM images of the material when its etched, Im sure they have that.

I always etch every crown, even if its not being bonded. IMO its impossible to etch emax for under 10 seconds without getting the white haze. if thats a problem, then every crown Ive ever done has been over etched. Im not sure what else you do other than dilute it more or leave it on for a few seconds..

LiSi is nice but im not sure its comparative to emax, color-wise its better, strength-wise Im not sure, Ive had some issues.. Im not even really seeing hardly any all ceramic crowns anymore, everything is done in zr except for veneers.. that is a trend I just noticed this year...

Not doubting you, I would just ask what you are watching with? Is it a 4.5% or a 9% HF?

 

[rkm rdt]

I etch but not silane.
I leave the residue to show it was etched only.

 

[Affinity]

I use the red ADS gel, I think its 5%, I also do not silanate them, I tell the Drs to do that after try-in

 

[Gru]

He's comparing it to the frosty white layer he sees in e max when etched, he did use this term that you used " frosty white " : if I don't see frosty white that means it is not etched well .

Read this:
https://leeannbrady.com/dental-materials/etching-protocol-for-e-max-lithium-disilicate and this:
https://www.ncbi.nlm.nih.gov/pubmed/25189110

 

[Sda36]

I use the red ADS gel, I think its 5%, I also do not silanate them, I tell the Drs to do that after try-in

I always etch & silinate as the post etching surface is SOOOOOO Easily Contaminated!!! I also asked Bisco what affects silinating days earlier than insertion would be. They told me the silinated surface/bond would be Enhanced, Not degraded.

 

[rkm rdt]

I was told the silinated surface was easily contaminated.
That was from Clincians Choice . Glad I was told that in bermuda.

 

[Gru]

I was told the silinated surface was easily contaminated.
That was from Clincians Choice . Glad I was told that in bermuda.

Send me to Bermuda and tell me anything you wish.