Maryland Bridge

taha

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I'm ask about Maryland Bridge what is the best metal you can use it for casting
And if there is some specific wax for building the frame work?
 
TheLabGuy

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I'm ask about Maryland Bridge what is the best metal you can use it for casting
And if there is some specific wax for building the frame work?

Use a refractory model if you're going to wax it (most accurate way). Non-precious metal tends to be the easiest thing to etch when it comes to metal. However, you can etch gold, but I don't do metal maryland bridges anymore. I always go with a Lava (all-ceramic) maryland bridge and I'm able to etch the lava by laying a very thin layer of glaze on the underneath of my wings, and that etches very well.
 
JohnWilson

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I'm ask about Maryland Bridge what is the best metal you can use it for casting
And if there is some specific wax for building the frame work?

I believe that NP metal must contain Be to etch. Make sure the one you use has that,

If you want to use a Noble or High Noble alloy you will need to tin plate the wings for any kind of bond

I suggest using pattern resin for wing restorations. It is exceedingly more accurate than any wax that you can use. I have used the refractory method with good success as well I just find I can do it in resin faster.
 
A

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I have used rexillium 3 and creation porcelain, seems to work. Refractory die as stated is best.
 
Al.

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I make a resin frame like John. I like to make sure it draws well before I invest so I dont have to worry about scraping the model seating it.

I make the wings in resin, take them off and trim them, then tack a wax pontic on, then connect it with resin. I give it an hour then remove and seat it a few times then seal my margins.
 
Travis

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Are you casting it without the refractory model Al?
 
Travis

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I am doing two now on one model and its a full arch impression both sides needing work and I do not have a ring big enough for a refractory model. I think I might send it out for a lava framework.
 
DMC

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I believe that NP metal must contain Be to etch. Make sure the one you use has that,

If you want to use a Noble or High Noble alloy you will need to tin plate the wings for any kind of bond

You guys never heard of the VA/MD bridge huh? Noble metal with salt crystals that have been washed away leaving little square undercuts for retention.

Travis, your refractory model baffles me. Sounds like a lot of time and money, and I don't understand why you are doing t6hat. Takes me 2 min to make a pattern using Zap-It and plastic as a connector. I can throw it against the wall, it's so sturdy. I finish the pontic and seal the margins with regular wax
 
JohnWilson

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I believe that NP metal must contain Be to etch. Make sure the one you use has that,

If you want to use a Noble or High Noble alloy you will need to tin plate the wings for any kind of bond

You guys never heard of the VA/MD bridge huh? Noble metal with salt crystals that have been washed away leaving little square undercuts for retention.

Travis, your refractory model baffles me. Sounds like a lot of time and money, and I don't understand why you are doing t6hat. Takes me 2 min to make a pattern using Zap-It and plastic as a connector. I can throw it against the wall, it's so sturdy. I finish the pontic and seal the margins with regular wax

I know this technique well, the wings can get a bit bulky to satisfy the mechanical retention the salt makes but it definitely stays put in the mouth when done right.
 
taha

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First thanks for everyone answer me. For me I max two type of wax stake wax and some cervical wax. And i use wiron 99 from bego
Any way i get good result.
 
CatamountRob

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Well my curiosity is piqued, can someone explain how to do this salt crystal thing? Thanks Rob
 
DMC

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It only works if you live in the South. ;)I'll make a youtube vid of it.

The guy who invented it is a 1/2 mile from me.
 
CatamountRob

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Cool can't wait to see it. Thanks ***, Rob
 
JohnWilson

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It only works if you live in the South. ;)I'll make a youtube vid of it.

The guy who invented it is a 1/2 mile from me.

Not sure about the "invented part" I have an old book somewhere that has this process outlined and it was printed long before I was born or adhesive dentistry was even thought of. This process relied on retention in the tooth as well the wing and utilized Zinc phosphate cement.

Still looking forward to your video to see if your technique mimics mine.
 
DMC

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Not sure about the "invented part" I have an old book somewhere that has this process outlined and it was printed long before I was born or adhesive dentistry was even thought of. This process relied on retention in the tooth as well the wing and utilized Zinc phosphate cement.

Still looking forward to your video to see if your technique mimics mine.

Dr. Peter Moon (material science)
and Dr Escherman of MCV in VA came up with the idea. My dad (now 70) was teaching C&B there when it happened. Unless you have another story, that's pretty much it. We used a special series of screen filters to get the salt to a certian size. That screen assembly is now at Goodwin Dental Lab in Richmond collecting dust. The kit was salt, red grease, slow and fast cyano-acrylate accelorator, and thick super glue. The kit looked home-made.

As you mentioned, the wings were a little thick. With modern cement and now Zirconia and implants.....this is pretty much obsolete.
 
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Clear Precision Dental

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show me....show me....
 
JohnWilson

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Dr. Peter Moon (material science)
and Dr Escherman of MCV in VA came up with the idea. My dad (now 70) was teaching C&B there when it happened. Unless you have another story, that's pretty much it. We used a special series of screen filters to get the salt to a certian size. That screen assembly is now at Goodwin Dental Lab in Richmond collecting dust. The kit was salt, red grease, slow and fast cyano-acrylate accelorator, and thick super glue. The kit looked home-made.

As you mentioned, the wings were a little thick. With modern cement and now Zirconia and implants.....this is pretty much obsolete.

I may have to eat my words which I hate but your gunna force me to dig around in the garage and potentially get bit by a black widow spider looking for that damn book. :)

What you briefly outlined is what I have done in the past as well, we still have the screen around that we used and sometimes use it to strain fibers from acrylic.

I will scan the page in the book just for fun if I find it this weekend.
 
CatamountRob

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I am interested in this technique (obsolete or not ) because I have a dentist who does MD bridges and has me put holes through the wings for retention. I would much rather do it this way because it kills me to put holes through my work. All of his cases are high nobel so etching isnt an option. Rob
 

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