Thursday, April 30, 2015

The Problems of Metal Fillings


Note the fractures and leaking interface
There has been much debate within the dental profession and in the public about metal fillings. Many countries have banned the use of these fillings. I personally haven't placed any metal fillings since 1997. They are often referred to as amalgams, silver fillings and metal fillings. 

There is much research covering this topic. Some of the studies were well designed, whereas others were poorly designed. Much of the discussion revolves around potential mercury toxicity. There are numerous studies that show how safe these amalgam fillings are. The American Dental Association has put out much information on how safe these fillings really are. I've heard some people say things like "you'll get more mercury from eating a can of tuna than from a mouthful of amalgam fillings".

I had a patient once that insisted that I place metal fillings in her mouth. She provided a stack of research that supported her position. She left my office because I wouldn't place them for her. Heck, I wouldn't place those things in my pets. I'm sure this statement will make some die hard amalgam proponents angry.

 I will not discuss whether or not fillings are safe from a mercury toxicity perspective. I will however discuss other reasons why I NEVER place metal fillings. 

I HATE metal fillings for other reasons:
  1. Metal fillings break teeth
  2. Metal fillings leak
  3. Metal fillings are ugly
I see broken teeth everyday at my offices that are directly attributable to metal fillings. There are a couple reasons why they break teeth.  
Note the sharp corners.
  1. They break teeth because of the sharp internal line angles within the tooth. What I mean is that there are sharp corners at the interface between the tooth and the filling. The fractures will often start there and spread just like a fracture on a windshield. The borrowed Google Image on the right demonstrates this process. The text is a bit hard to read though. This is not an issue with tooth colored fillings. Tooth colored fillings have rounded line angles.
  2.  
    Fractures radiating from the filling
  3. They also expand and contract in response to temperature changes at different rates compared to tooth structure. Tooth colored fillings on the other hand expand and contract at comparable rates to tooth structure. This difference in the expansion rates is another major reason for tooth fractures.

  4. These fillings also leak because they aren't bonded to the tooth. So, tooth decay will begin at the tooth/restoration interface. Tooth colored fillings on the other hand are bonded to the tooth. Therefore, the interface is much less susceptible to recurrent decay at the interface.

    It goes without saying, metal fillings do not appear natural and are incredibly ugly. Enough said.
  5. They also expand and contract in response to temperature changes at different rates compared to tooth structure. Tooth colored fillings on the other hand expand and contract at comparable rates to tooth structure. This difference in the expansion rates is another major reason for tooth fractures.

  6. These fillings also leak because they aren't bonded to the tooth. So, tooth decay will begin at the tooth/restoration interface. Tooth colored fillings on the other hand are bonded to the tooth. Therefore, the interface is much less susceptible to recurrent decay at the interface.

    It goes without saying, metal fillings do not appear natural and are incredibly ugly. Enough said.
  7. They also expand and contract in response to temperature changes at different rates compared to tooth structure. Tooth colored fillings on the other hand expand and contract at comparable rates to tooth structure. This difference in the expansion rates is another major reason for tooth fractures.

These fillings also leak because they aren't bonded to the tooth. So, tooth decay will begin at the tooth/restoration interface. Tooth colored fillings on the other hand are bonded to the tooth. Therefore, the interface is much less susceptible to recurrent decay at the interface.

It goes without saying, metal fillings do not appear natural and are incredibly ugly. Enough said.


The amalgams, recurrent decay and fractures were removed and restored

Amalgam restorations have been available for over 100 years. They were the best option for many of those years. Many advancements have been made over that time. There are much better options now. Ask your dentist what options are best suited for your unique circumstances.


Dr. Cisneros maintains a practice in Freeburg and Columbia, IL. Both are in the Greater St Louis, MO area. For more information on a wide variety of subjects, please visit www.advanced-smiles.com