Archive for the ‘Porcelain Crowns’ Category

Am I allergic to the metal in my crowns?

Thursday, May 19th, 2011

I just read that you can have allergy reactions due to metal crowns (I seem to have allergies to many earrings, regardless of gold or silver). I did not think about this prior to my current crown work. My dentist just implanted two temporary plastic crowns (next appt. is in 2 weeks). Since I could not afford porcelain crowns, my insurance will only pay for metal (teeth 29 & 30). The dentist is going to fuse porcelain over #29 (which I have already paid for). Now upon reading about this metal allergy problem, I do not know what to do.

This is the first time at this particular dentist through my insurance. I have my qualms concerning him (different reasons) & would like a second opinion concerning my questions. I would appreciate your advisement in this matter. Thank you!
- Teresa from New York

Teresa,
You’re asking a good question, and you’re asking it in time to make sure you don’t have a problem with these crowns. And, unfortunately, this is what you get when your insurance company creates these preferred provider lists. They pick the cheapest dentists who use the cheapest materials, and you can get problems like this.

It is the responsibility of your dentist to ask enough questions to prevent any sensitivity reaction to any metals that are in any crowns placed in your mouth. His medical history form should ask specifically if you have any issues with metal sensitivity. But, judging from your worries, you don’t believe that you were asked this question.

When people have metal sensitivities or metal allergies, the offending metal is almost always nickel, chromium, or beryllium. And yes, these metals are used in cheaper metal alloys for dental crowns including porcelain fused to metal crowns. They are also used in some gold and silver alloys in jewelry because they’re relatively light and strong and won’t tarnish.

Here’s what I would do at this point. I would call and ask to speak with the dentist, and would inform him directly that you have metal allergies, and so the alloy used in your crowns needs to be either precious metal or semi-precious metal – no base metals. If they don’t let you speak directly with the dentist, be sure to let them know that this is a serious issue and write down the name of the person you end up speaking with, so that you can follow up. And since it doesn’t sound like you trust this dentist, I would go one step further and would tell him or his staff person that you want a written copy from him with a list of the composition of the metal alloy used in your crown before the crown is permanently cemented in your mouth, or else you will not consent to having it cemented. The dental laboratory will send to the dentist a little certificate with a list showing the composition of any metals used in the crowns, and you would be asking for a copy of this. Look it over and make sure there is no nickel, chromium, or beryllium in the alloy before you let them do anything in your mouth, on the day you come in to get these crowns cemented. Don’t even let them take the temporary crowns off until you can see this certificate – that way you are completely free so you can walk out if they don’t produce it. If they have nothing to hide, they should readily provide this information.

Other links:
The metals that we use in the gold alloys of gold fillings do not contain any of these base metals: nickel, chromium, or beryllium.

Follow-up – See Teresa’s follow-up e-mail and our answer.

This blog sponsored by Boca Raton TMJ dentist Dr. David Kagan.

My porcelain crown keeps falling out.

Friday, March 12th, 2010

I have porcelain crowns on some of my top teeth. I have had problems with them falling out. This weekend I was eating something and bit down and I didn’t know my tooth fell out – I bit down on it – it shattered and apparently I swallowed most of it. I had it done at my family dentist in 2004 and have been back there several times to have crowns re-cemented in. He usually doesn’t charge me to re-cement but now he wants to charge me $1,100.00 for a new crown. I told him I would pay cost for the crown but that was it, that it should not have fallen out to start with. Is it common to have them fall out as much as mine have? Is this something that I have to pay for?
- Susan from Georgia

Susan,
No, this shouldn’t be expected, that a porcelain crown keeps falling out. If they’re done right they won’t ever fall out. But I can understand why your dentist wants to charge for this, because now he has to make it from scratch, and it’s kind of expensive for him to do this.

What holds crowns in is the near parallelism of the way the tooth is prepared. The more parallel the tooth is prepared, the stronger is the retention. But if the tooth walls are made TOO parallel, there is a risk of what are called undercuts, and the crown won’t fit at all. Different dentists have different levels of comfort with how parallel they will make their preparations. The less parallel they are made, the easier it is to fit the crown.

But then with all-porcelain crowns, they are also bonded to the teeth. And if they are properly bonded, they don’t need a lot of retention in the design.

I’m suspecting that your dentist doesn’t know how to bond porcelain crowns. They’re supposed to be bonded to your tooth, and they get most of their strength from the bonding procedure. It sounds like your dentist has simply cemented it in instead of bonding, as that’s the only reason I could think that an all-porcelain crown would just fall out like that.

Yes, I would say that your dentist should just replace this for no charge. But I don’t believe he’s legally required to do this, and if he has lots of these crowns falling out, I imagine he’s getting tired of doing this for free, and it’s hurting his bottom line.