Does Layered Zirconia Fracture Easily?

Does Layered Zirconia Fracture Easily?

Short answer, NO!

Long answer, when it first came out, some laboratories handled it wrong and fabricated a few units poorly, going against all of the porcelain veneering rules they have used for 75 years, (PFMs) and giving layered zirconia a bad name.

Labs thought zirconia was bulletproof. Nope!

It’s really simple! Veneering porcelain needs to be supported.

When you fabricate a PFM, the substructure is waxed to full contour then cut back 1.5mm all around and occlusally for the ideal support of the veneering porcelain. If veneering porcelain is close to 2mm thick it leaves the supporting protection of the substructure and is prone to cracking, chipping, and fracturing.

The exact same rules apply when layering or veneering zirconia. The technique is a little different but the theory is the same. Design the tooth to full contour (virtually), then hit the cutback button and it immediately cuts the crown back 1.5mm in preparation for the veneering porcelain.

The unbreakable law for veneering porcelain has always been keep it within 1.5mm for safety and strength.

Does layered zirconia fracture easily? NO! Not when it is fabricated correctly.

Scott Emett

What’s Up? Gold!

What’s up? The price of gold, that’s what.

10 years ago we used to watch that price like a hawk. It seemed like we lived or died with the spot price of gold. When it was low then gold crowns and big pfm bridges were no problem for anyone. When the price of gold was high then a laboratory got a phone call before every big case just for an estimate of the cost of the gold. If the estimate was too high then there was a discussion of how to cut down the gold content or the amount of metal needed for that certain case.

Right now the price of gold is over $1,200 an ounce. That would blow the minds of all of the dentists and insurance ladies in the office. We struggled when gold started towards $800 an ounce. That was the real danger zone and sometimes dictated treatment because of the high cost of gold. No one gave it a second thought when it was at $250 an ounce. When the $800 an ounce price rolled around it changed the thinking of insurance companies and doctors who were hesitant to quote the high price of a restoration.

Now, with the price at over $1,200 an ounce no one even seems to care. It certainly does not dictate treatment and it is hardly even a consideration. Why is that?

Gold is the standard for Dentistry. Gold is highly biocompatible, it had the same wear characteristics of enamel, the margins can be perfectly burnished down and closed, it does not chip or break or crack or fracture, and it has over a hundred years of actual in mouth proven success.

In Riverside Dental Studio right now, our clients prescribe zirconia 2/3rds of the time. The other 3rd is shared by pfms, EMax, and other restorations such as gold crowns. When I got into this industry 38 years ago, all I did was gold crowns! That lab fabricated 250 gold crowns a month. That same lab today does 5 gold crowns a month.

The most ideal dental material in the world has been pushed aside.
There are two reasons we have stopped using gold.
One reason is the subject we have been talking about in this blog. That huge reason is price. The cost of gold begin to be prohibitive and begin to dictate treatment, so alternatives were sought after. The other reason is aesthetics. Vanity has been a huge influence. The General Public does not want gold showing in their smile. They want straight, white, beautiful teeth without a flaw.

That is it! Very simply, dentists have caved in to cost and vanity. In my short time and limited experience on this earth, I have never seen anything turn out good that was based on low price and vanity.
Just saying.

Scott Emett

Do you “Get It?”

Do you get it?

Wow! I was shocked!
For sure I was pleasantly surprised. I went to an appointment with a potential new client. He had heard about my lab and wanted to talk to me about lab communication and about his laboratory work.

I set down in his office and we discussed occlusion theories and time schedules and material selection.   On a computer monitor he pulled up a large case for us to go over.

He had taken pictures from all angles including lips at rest, full smile and profile shots. Using mirrors for occlusion and lip retractors where needed he did a great job. Not only that, but they were high quality pictures. Next, he was holding the correct shade tabs showing the number of the shade and holding it incisal edge to incisal edge so they were on the same angle as the teeth. Thus facilitating accurate shade matching.

My surprise did not just stop there.

He had taken a horizontal stick bite and a vertical stick bite. I know it was done well because he took a picture of it. When I looked at the impressions they were incredibly well done. The preps looked great for the intended restorations and he had gotten a great impression.

Now he pointed out some issues with tissue and other concerns he had and concerns the patient had. I was taking notes as fast as I could write. I was thinking the whole time that this is how these cases should go. With all of this great information, all the lab had to do is follow directions. Ok, I get it.

These restorations we’re going to turn out fabulous because the doctor and the patient and the Lab are all on the same page. He really did not need a wax up in this case because we were copying the pre op. The patient’s problem was in chipping and in some tissue recession that was showing some tooth surface at the gum line.

This case was going to be a slam dunk. There are many dentists that do this kind of high quality work. But it seems like I have taught most of the ones that send their work to my lab. It is such a pleasant surprise to walk into a new client’s office and have him already knowing how important lab communication is.

This case is highly predictable and the results will be everything that the patient and the doctor expected.

Obviously a little bit of work at the beginning will pay huge dividends at the end. The old saying that you should measure twice and cut once is so very true. Does he get it? YES!

He “gets it”!

Scott Emett