UCLA's tips n tricks

[Andrew Priddy]

I've been doing a TON of UCLA's lately, so thought I might start a thread on UCLA's...
Post tips on successful waxing/ casting/ spruing, and any thing relevant to UCLA's

 

[JohnWilson]

1) Cast it like its solid, sprue to the thickest mass, we use a prefab sprue that has a bulb in it to help with porosity sprue at a less step angle to the pattern to eliminate undue stress on the invest going in the channel
2) Don't use pd alloys its the absolute worst bond to the Non ox gold base. 65sf has been show as the best alloy.
3) change your investment ratio to select ZERO expansion of the pattern
4) eliminate flash on the interface by reducing the force on your casting machine
5) clean the junction of the interface to the wax pattern with wax solvent and immediately use denatured alcohol to clean any residue
5) Never ever divest the pattern with Alox or glass beads only use acid.
6) Thread floss through the hole in the pattern and slowly pull it out as you pour the investment in the ring (thank you DLN)
7) Do more Zirconia and put more money in your pocket and limit veneering issue over time
8) Add additional time to burnout to make sure plastic completely burns out clean.

Thats just a few off the top of my head and yes its a great technique to have in your arsenal but I really feel its an inferior more costly product with no upside with modern technology. Strategy Milling will soon have provisions for high noble milled ceramic alloy. I assume, it will only be time before they offer a service to mill perfectly dense Implant patterns in the future if you want to still offer metal ceramics. It will require a cad base as a cemented interface but the cost savings alone will be huge over traditional Gold interface UCLA's + Alloy.

Now where did I put my mouse...

 

[Andrew Priddy]

3) are you saying not to use expansion liquid?

 

[Andrew Priddy]

John. we don't "push" UCLA's on the market... we do a lot of CAD as well..
But, we have Dr's that demand UCLA's, and we charge for them

 

[Gru]

If there are 2 thin areas close to the cylinder, double sprue to the 2 thickest parts (like on a premolar w/ little m-d room).

 

[Andrew Priddy]

I run a stub off the thin area for a reservoir.. and sprue to the thickest part
works great

I never get a dry cast at the cylinder, or even a short cast

also, I've done a few DPM with Argen and a cemented TiBase while I was at another lab.. worked well, but at the moment, cast UCLA's are on the menu and selling.
we are also so diverse in what we can do, we can easily shift to what the market wants

 

[aqdental]

3) are you saying not to use expansion liquid?

The idea is to reduce expansion to eliminate any possible gap between investment and interface to avoid alloy flowing where you don't want to. An old technique was to coat the interface area with white-out to protect such area. Reducing torque on casting machine and keep interface clean also works. Choose an investment with low expansion so you can still use some liquid for better surface finish.

 

[rkm rdt]

Try using a brass bristle brush to polish the interface.

 

[Andrew Priddy]

Try using a brass bristle brush to polish the interface.

with some comet on it

 

[Andrew Priddy]

The idea is to reduce expansion to eliminate any possible gap between investment and interface to avoid alloy flowing where you don't want to. An old technique was to coat the interface area with white-out to protect such area. Reducing torque on casting machine and keep interface clean also works. Choose an investment with low expansion so you can still use some liquid for better surface finish.

white out doesn't burn out?
i'm using schien vest with 4ml liquid 20ml water
my surface finish is excellent, no complaints there
I do get some sporadic flash that I need to eliminate
it really, really sucks on Synoctas.... even though I carve a moat and keep the interface extremely clean.. i'll start working on some of the tips posted

 

[rkm rdt]

Ya,what would I know

 

[kimba]

it really, really sucks on Synoctas....

let me know when you solve this !!!! I found DNL because of this problem , only on synoctas.

 

[aqdental]

white out doesn't burn out?
i'm using schien vest with 4ml liquid 20ml water
my surface finish is excellent, no complaints there
I do get some sporadic flash that I need to eliminate
it really, really sucks on Synoctas.... even though I carve a moat and keep the interface extremely clean.. i'll start working on some of the tips posted

No it doesn't. I use it to mark my rings as well. Reduce liquid content and you should be ok. I read an article years ago of S Kataoka ( I think that's is name) and he was using white-out for that purpose. I never used myself for that but I started using it for marking my rings. Clean very well the finish line of your waxup also.

 

[Andrew Priddy]

let me know when you solve this !!!! I found DNL because of this problem , only on synoctas.

I've gotten to the point where I cut a moat around it and then laser weld it after casting.. also, I've taken an analog and drilled the engagement out of it, and use it with polishing compound to clean out flash.. works well, but very time consuming

 

[French Cadman]

@ andrew, show us a picture of the connection casted , that is more interesting than the dental model ....

French thanks !

 

[Andrew Priddy]

UCLA's, not casting the connection..

tried some whiteout today, we will see how it works... if it doesn't, i'll have blown a lot of $$ in parts... there is a possibility that tomorrow could really suck

 

[Affinity]

I like to carve around the interface so there is a definite stop and no molten gold flows over the interface.

 

[Andrew Priddy]

we call that a moat.. I do that mostly on Synocta's

 

[rkm rdt]

I call that a plaque trap.

 

[Affinity]

RKM, you know, it has porcelain over it...