What investment is best for an Emax bridge?

[Heidi]

Hello, I've been pressing emax for years, somehow nobody has ever requested a bridge until now. I have a 3 unit anterior bridge to make. I have been investing with Sheinvest without any issues. But I know that that's not a great investment for bridgework. I want this thing to come out great the first time. So what investment and ratio would you recommend, also what burnout temp. I usually do a fast burnout at 1600.

 

[pjd cdt]

I use Zubler 50/50. But that's with a milled wax up

 

[doug]

We use Microstar for everything without problems

 

[user name]

Just curious...why is that not a good investment for bridge work, why are you using it, and why do you burnout so hot?

 

[Heidi]

Just curious...why is that not a good investment for bridge work, why are you using it, and why do you burnout so hot?

I've used it for bridges and they were not fitting well. I burnout that hot because that's the temp the person who taught me did. It worked. I'm open to suggestions or ideas?

 

[Heidi]

I'm not saying I was taught correctly, but it worked so I continued it. I have been using sheinvest, letting it set for 25 min and then burnout at 1600 for 25 min. The only things I invest are emax and gold crowns. All my metal framework I design on my scanner.

 

[Gru]

Microstar HS works well for everything we do. My ratio for emax bridges is 29:21 200g 17min bench set, 2min after ring removal and end scrape to let steam out. 850c (1562f) burnout 1:15 hr. Zero mis-presses. If you are using HenrySchien HS vest, the ratios should be very close to the same (used to use it, still do for CrCo) bench set 30 min.

 

[user name]

Wowzers. Speedvest, Microstar, Zubler 144. I know they all work great. 50/50 liquid/water or up to a couple cc's more liquid/less water. Assuming a 200gm ring, bench set 17 minutes, take the ring and base off and let set 2 or 3 more minutes to sweat and then into a 1553-1562 (845-850c) for 1 hour.

 

[CreDes]

I use Microstar and just follow their directions.

 

[Gru]

Which directions? The ones in the box of power, or Jensen's?

 

[Heidi]

I mostly use 100 gm ring. 1 woman lab here.

 

[Gru]

Gotta use 200g for emax bridge or a super ring, otherwise they split.

 

[Marcusthegladiator CDT]

Definitely use a 200 gram ring for your bridge. And look at Ivoclars PDF for emax press and they show you a 3 unit bridge being sprued and invested properly.
I use Cerevety from Shofu at 30% concentration, 842 burnout.
You want to press at the lowest burnout and press temp possible and still get a successful press. So I have everything dialed in.
LT ingots at 913 and HT at the usual 910.
Incredibly small reaction layer and very acceptable surface texture dialed in here.
But it's all different everywhere you go. Altitude, Humidity, Furnaces... Hell I've never Calibrated the burnout oven... what for? 842 works wonders.

 

[Tayebdental]

Bego investment and Zubler pressing furnace here, with 99% reaction free layer.

 

[rkm rdt]

Have you considered a zirconia frame ?

 

[aqdental]

Hi

I've used it for bridges and they were not fitting well. I burnout that hot because that's the temp the person who taught me did. It worked. I'm open to suggestions or ideas?

Hi Heidi, if your investment is good for singles should be good for bridges as well. Make sure your waxup is fitting well and be carefull during lifting to avoid distortion ( especially if you use wax). You can try 2 different mixes, one for the copings and one to fill the ring ( with less % of liquid). The size of the span will dictate that %. Only if the Pontic span is equal to the diameter of the prepped units you can safely use the same mixture of investment. Longer span = less liquid. If you don't want to use two mixture than use less % of liquid than you normally would but expect some internal adjustment for the two copings. Think of the Pontic area as an inlay ( fitting between the two medial walls of the preps). Hope this helps.

 

[Jason D]

Have you considered a zirconia frame ?

I'm in total agreement, I have seen emax bridges fail repeatedly from a number of labs, from production to boutique.
To make the connectors large enough is a pain, they become unesthetic, and not worth the effort for a 400ish strength...We politely steer our clients to a more reliable result.
In the rare case where they still want it after our explanation, we do not warranty them.
Emax is great and all, but bridges, no thanks.

 

[KentPWalton]

Whatever investment you choose to go with, I suggest you follow the manufacturer's instructions

for use. Investment is a tricky thing, and will vary from state to state depending on the

humidity. I would go with the manufacturer's suggested settings and then contact them

if they have any further suggestions.

 

[Wyolab]

I agree, a lower temp for longer will probably leave you a cleaner press. Is that 1600 Fahrenheit? If so that would be about 870 Celsius. Marcus are your temps in Celsius or Fahrenheit? My pressing oven is Celsius and my burnout oven is Fahrenheit, so I burnout at 1565f and peak pressing temp is 910c. I use scheinvest and with a 100gram ring I use 16ml liquid 8ml h20 and place in the hot oven at 1565f after 20 minutes for one hour before pressing. I don't do bridges without a zirconia frame though. I used shofu for a while and had less of a reaction layer.

 

[AdrianB]

I use Gallaxy 2 from Talladium, 15mil liquid, 10 mil water. You may need to use double size ring. I pressed a few 3 units bridge, and some 4 units . Not recommended, but i did it. Adrian.