Stone Plaster Gypsum

[Jack_the_dentureman]

I wonder which plaster Typ IV (hard) choose. I began to compare different manufacturers and noticed that declared expansion ranges is between 0.10 and 0.07 %. Most of them are 0.08% and it seems decent.
But the compressive strength is very different from ~53 MPa to 104MPa. I know there is more, like Hardness, thixotropic, working time, chipping....
Gc Fujirock EP compressive strength is 53 MPa, i use it before and it did not seem too weak.

So what are your experiences with plaster from different brands. Have you noticed any differences or problems?

 

[gallagerdental]

Sorry I'm a little confused. Do you want mounting plaster? I use Fujirock EP for my C&B, white plaster for mounting, yellow stone for full dentures, & acrylic partials, & Veri-Die (stone) for chrome partials ( yellow for processing Dups ). As you have said each has its own range & purpose.


Sent from my iPhone using Tapatalk.

 

[JMN]

I wonder which plaster Typ IV (hard) choose. I began to compare different manufacturers and noticed that declared expansion ranges is between 0.10 and 0.07 %. Most of them are 0.08% and it seems decent.
But the compressive strength is very different from ~53 MPa to 104MPa. I know there is more, like Hardness, thixotropic, working time, chipping....
Gc Fujirock EP compressive strength is 53 MPa, i use it before and it did not seem too weak.

So what are your experiences with plaster from different brands. Have you noticed any differences or problems?

I always liked Begostone. It's a bit pricey, but never did me wrong. Very smooth pour, very good plastiscene stage, nice working time.Never needed a surfectant to pour anything the doc could impress, no matter the angles/sharpness/thinness.

Anything with "resin" always left a residue in my sink and trimmer, bowls, etc. I may just not be in on the secret to dealing with it, but it left a bad impression .

 

[kcdt]

I wonder which plaster Typ IV (hard) choose. I began to compare different manufacturers and noticed that declared expansion ranges is between 0.10 and 0.07 %. Most of them are 0.08% and it seems decent.
But the compressive strength is very different from ~53 MPa to 104MPa. I know there is more, like Hardness, thixotropic, working time, chipping....
Gc Fujirock EP compressive strength is 53 MPa, i use it before and it did not seem too weak.

So what are your experiences with plaster from different brands. Have you noticed any differences or problems?

My first suggestion is that the type of gypsum used should match the procedure.
Without specifics, the question is too open ended to answer helpfully.

So,
Master cast?
A. Cast RPD
B. Thermoplastic injection? (should be type V)
C. PMMA denture base (avoid resin impregnated, which usually rules out type IV)
D. crown and bridge sectional dies.

Both A and D are good candidates for type IV for gypsum
I used Fujirock for my PFM/gold for years, then switched to ResinRock, which I preferred at a better price point as well.

 

[AJEL]

Nylon type IV is ok but not always needed, the beta stone most think of as yellow (105) for dentures & processing partials. Acetal depending on type requires a typeIII expansion stone for Myerson, and a Beta yellow for Flexite Acetal, the new injected Vinyls Snowrock and soon a Myerson version are best with Beta, the new Flexite T-Val poly olefin is injected at 245*c and I use type IV.

 

[JKraver]

For acrylic dentures you could get away with only having cheap lab plaster and a lab stone like microstone. For partials I always use a type 4 unfortunately I am running through the last of my resinrock before I get the non resin type 4