LiSi (Questions)

[TheLabGuy]

Rob, Did you find the Lisi pressing and firing parameters? I've pressed a few and they cracked.

Yes I did...I use 890C. I've been pressing LiSi since it's been released, great results. Also, the pressing charts are a great starting point, they help in narrowing your own parameters down but each one of you will have to narrow it down even more from your starting point...when it comes to pressing, a lot of variables (i.e. power supply, elevation, oven, etc...) to take into account is why you need to think of the pressing charts as a starting point and then narrow from there is my advice. Hope that helps.

 

[sidesh0wb0b]

Yes I did...I use 890C. I've been pressing LiSi since it's been released, great results. Also, the pressing charts are a great starting point, they help in narrowing your own parameters down but each one of you will have to narrow it down even more from your starting point...when it comes to pressing, a lot of variables (i.e. power supply, elevation, oven, etc...) to take into account is why you need to think of the pressing charts as a starting point and then narrow from there is my advice. Hope that helps.

my first press was yesterday. started with the book temp of 898C
will divest soon and see

 

[TheLabGuy]

my first press was yesterday. started with the book temp of 898C
will divest soon and see

My issue when I first started was I was getting the orange peel or pits...obviously, thought back to my e.max days and that tells me way too hot. LiSi presses quite a bit lower than e.max. Also, to find the sweet spot per say, you'd be surprised how low you can go (yeah I know, I sounded like a limbo contest right there).

 

[sidesh0wb0b]

My issue when I first started was I was getting the orange peel or pits...obviously, thought back to my e.max days and that tells me way too hot. LiSi presses quite a bit lower than e.max. Also, to find the sweet spot per say, you'd be surprised how low you can go (yeah I know, I sounded like a limbo contest right there).

so far so good, havent looked under the scope yet but they blasted clean with no reaction layer and seem smooth as the wax patterns originally.

 

[sidesh0wb0b]

ok, so no reaction layer was found...but 898C is a bit hot. there was some minor pitting from overheating on the surface near the sprue. will drop to 890C and see how the next few presses go. that being said, was decent to work with... did a full contour lower anterior out of HTE59 and some B2/B3 staining. came out very nice and was easy to stain.
full disclosure: im trying not to be negative...I am NOT a fan of group shade materials.

 

[Sda36]

ok, so no reaction layer was found...but 898C is a bit hot. there was some minor pitting from overheating on the surface near the sprue. will drop to 890C and see how the next few presses go. that being said, was decent to work with... did a full contour lower anterior out of HTE59 and some B2/B3 staining. came out very nice and was easy to stain.
full disclosure: im trying not to be negative...I am NOT a fan of group shade materials.

[emoji4]

Sent from my LG-H812 using Tapatalk

 

[sidesh0wb0b]

update:
i really dont like the group shades. all the extra time i had from not needing to invex and sandblast again was eaten up by multiple stain fires to get where i needed to be. where i would have been with one single fire at most on an emax crown.
that being said, they come out looking great. no complaints there

 

[Car 54]

update:
i really dont like the group shades. all the extra time i had from not needing to invex and sandblast again was eaten up by multiple stain fires to get where i needed to be. where i would have been with one single fire at most on an emax crown.
that being said, they come out looking great. no complaints there

Agree, that's why I've passed on it so far, the LT group shades....or in GC's case, lack of in that group.
A nice variety with the MT's, but 50 - 60% of the time, I use the LTs.

 

[Affinity]

what stain/glaze are you using?

I had horizontal cracks in my veneer case.. fired out with another firing.. but it makes me very nervous. Never had cracking issues with GC porcelain like this... or emax for that matter.

 

[sidesh0wb0b]

what stain/glaze are you using?

I had horizontal cracks in my veneer case.. fired out with another firing.. but it makes me very nervous. Never had cracking issues with GC porcelain like this... or emax for that matter.

ivocolor stains, insync glaze

 

[millennium]

what stain/glaze are you using?

I had horizontal cracks in my veneer case.. fired out with another firing.. but it makes me very nervous. Never had cracking issues with GC porcelain like this... or emax for that matter.

How do you fuse a crack in Lithium Disilicate without melting it?

 

[Affinity]

Luckily these were cracks in the layered porcelain, however I have in the past, and even read in the FB group of refiring the core, covered in peg putty, it does work, I just repress though. I have had cracks in the pressed lisi porcelain after firing as well though. just fyi

 

[millennium]

Luckily these were cracks in the layered porcelain, however I have in the past, and even read in the FB group of refiring the core, covered in peg putty, it does work, I just repress though. I have had cracks in the pressed lisi porcelain after firing as well though. just fyi

Thank you for the explanation. A good while back I used to press Pentron's OPC pellets and could fuse cracks in them with the powder they provided for that.

 

[Car 54]

Thank you for the explanation. A good while back I used to press Pentron's OPC pellets and could fuse cracks in them with the powder they provided for that.

Their repair material. I remember that.

 

[adamb4321]

Hi, after reading through this thread and seeing Al's beautiful work I've got a veneer upper 3-3 case that I'd like to press using LiSi.

Shade is B1 preps have around 1mm facial reduction and are cut through the interproximals with 0.5mm to 1mm space between the preps there is between 1mm and 2mm Incisal reduction.

So I'm after pellet recommendations for monolithic veneers. The underlying tooth colour is a3/a3.5 maybe monolithic is going to be a struggle?

 

[sidesh0wb0b]

Hi, after reading through this thread and seeing Al's beautiful work I've got a veneer upper 3-3 case that I'd like to press using LiSi.

Shade is B1 preps have around 1mm facial reduction and are cut through the interproximals with 0.5mm to 1mm space between the preps there is between 1mm and 2mm Incisal reduction.

So I'm after pellet recommendations for monolithic veneers. The underlying tooth colour is a3/a3.5 maybe monolithic is going to be a struggle?

you may be able to get away with an MTB1 ingot if the dr and patient are okay with a warmer looking B1...prob wont mask it completely but will look nice with the blend from a warm A3 stump...thats just me. we do about 75% of our all ceramics in Lisi now with most of those being MT ingots

 

[subrisi]

I wouldn't touch the case until I get a stump shade.
Also make sure to press all of them with one ingot. If this is not possible, take ALL ingots out of the sleeve and make sure they are exactly the same color. I returned my LISI because the first 2 sleeves I opened, there was a significant color difference between the ingots in the sleeve. If they can not even provide even coloring within the same batch, I would not want to use it. I have lost all my trust in that material.

 

[adamb4321]

Thanks for the info guys. Getting Drs to give stump shades is an uphill struggle. After a long conversation about the case in which my opening question the the Dr was “are the teeth discoloured/dark” and being told “no” the Dr casually dropped the information that the stump shade was A3/A3.5. This was while I was typing my first post.
Sideshowbob, I’m a little hestitant about using MTB1. I designed the veneers for milling, the thinnest is about .7mm. I think the underlying shade will influence too much. I’m thinking maybe using the MTB00 it’s that or E.max LTBL3 and the. Some layering.

 

[ps2thtec]

ok, so no reaction layer was found...but 898C is a bit hot. there was some minor pitting from overheating on the surface near the sprue. will drop to 890C and see how the next few presses go. that being said, was decent to work with... did a full contour lower anterior out of HTE59 and some B2/B3 staining. came out very nice and was easy to stain.
full disclosure: im trying not to be negative...I am NOT a fan of group shade materials.

So b0b, did you settle on 890C? The first several I pressed seemed fine but recently started seeing the hot pits. Pressing by their #s at 898 but set hold an extra five minutes with Super ring. Have ep3000 oven. Also noticed the press function runs longer too. Or anyone else with insight.........Thanks!

 

[sidesh0wb0b]

So b0b, did you settle on 890C? The first several I pressed seemed fine but recently started seeing the hot pits. Pressing by their #s at 898 but set hold an extra five minutes with Super ring. Have ep3000 oven. Also noticed the press function runs longer too. Or anyone else with insight.........Thanks!

ep3k here as well. i left it at 890. on really big units i might end up with some pitting which sucks. just havent had the time to keep toying with it. so ive left it as is