This is the first comparison case I am doing to test a new crown technology. Glidewell Labs has a new type of crown for back teeth made out of zirconia, a high strength ceramic. Like gold crowns, they are virtually unbreakable, don't require a lot of tooth height. Unlike gold crowns, they are tooth colored.

Many people know about 3M's Lava crowns. They are porcelain fused to zirconia. They are beautiful in the front, but they are expensive to produce, and the porcelain is relatively fracture prone. Few problems on front teeth, but using them on high-load molars is risky; I've actually had a couple of them break myself. In every documented case of failure, (I'm talking the published clinical studies) the outer porcelain breaks off, leaving the inner zirconia intact. So the folks at Glidewell decided to make the entire crown out of zirconia.

The benefit is a lower cost, more conservative tooth reduction (dental colleagues, they're claiming 1mm occlusal reduction), and better appearance than a gold crown. The tradeoffs: harder for the dentist to adjust, harder for the dentist to repolish, and poor translucency. (which is why they are meant for back teeth) I decided to ask my friends at Glidewell to make me two crowns: a PFM, the tried and true porcelain fused to metal crown, and a new Bruxzir, the all-zirconia crown.

Here's the photos:

As you can see, the zirconia crowns hold up very well to the PFM crowns that go on 90% of my patients. And compared to a gold crown, they are hugely better. As a matter of fact, this patient chose the zirconia crown. She said it fit like a glove, and she loved the appearance much better. We agree. We're doing another case to confirm our very positive initial findings.

Here's a successfully finished remineralization case. We started with non-decayed teeth with white spots. We were going to do veneers, but we thought we would try this conservative non-surgical approach first. This is what they looked like before the treatment:



Lots of white spots on the cervical third of the tooth (that's the part near the gumline). The reason you get congenital (born with it) white spots is simple: there wasn't quite enough calcium right there to form strong, clear enamel. The weaker, hypocalcified enamel is frosty white in appearance, and often appears in bands or spots. You can also get white spots from too much plaque or too much acid in your mouth. The plaque contains bacteria that make lactic acid, which dissolves the calcium out of the enamel, causing it to break down and turn frosty white. (neglect it longer, and the enamel breaks down completely, leaving a hole we call a cavity)

I'm not a big fan of cutting down well shaped teeth if I don't have to. So we decided to try a protocol by GC America. The idea is simple: if the tooth is missing calcium, add it back in. MI paste is calcium phosphate (what your bones and teeth are made out of) wrapped in milk proteins that make it easier to absorb. You just have to soften the surface of the tooth a little bit to get it to soak in deeper. On the first visit, we acid-etched the teeth, and then polished them with pumice. This breaks down the outer layer of weak enamel. Then we applied MI paste, a white calcium phosphate cream made from dairy proteins, to the teeth for five full minutes. We instructed our patient to apply this creamy white paste to her teeth every night after brushing. We repeated the whole process for four visits, over a period of about two and a half months.

Coffee staining was the only complication. Even though we told her not to drink it, for some, the urge is just too strong. The treatment makes the teeth relatively porous and permeable to the MI paste, but it also makes them more susceptible to staining beverages like coffee and red wine. We had to spend a couple of weeks whitening and polishing to under the coffee. For future cases, I will strongly recommend Ultrabrite Advanced Whitening toothpaste during the treatment period, because it's a strong stain fighter--Consumer Reports said it is the best stain remover of all toothpastes. And it's a buck a tube at Walmart.

Here's what the teeth looked like after four treatments. I blew them dry to show the detail of the enamel. If they are wet (which they usually are), they look just about perfect.



After all was done, I applied a clear coat to the teeth (which should hopefully allow her to drink. There's a tiny little white spot on the right central incisor (#8), but it's usually hidden under her lip, and she really wanted to be able to drink coffee again. If we gave it a few more treatments, we probably would have gotten it all out.

All in all, this was a very successful re-mineralization case. We got rid of the white spots, and saved her from two very expensive (and difficult to match) veneers. A lot of dentists will read this case and think "I could have made a lot more money and been done much quicker if we did veneers." My philosophy is if you drill less, you might make less, but patients appreciate conservative care. After all, it's what I would want done in my own mouth.

Originally posted on my photodontist blog.