Expert: Frederick R. Liewehr DDS, MS, FICD - 8/21/2004

Question
To give you alittle history, dont know if you really need it. My braces have been off since 1994, and the last time I went to the dentist was in 1998 (really bad I know) and I had 2 fillings done, and had a serve allergic reaction to the carbucaine/mevocaine that was used. Due to that reason I have been terrified to go back.
I am "missing" my wisdom teeth and 2 other molars. They simply arent there, and do not appear on dental x-rays.
Today I discovered that somehow within the last 24 hours the filling that was on the "top" of my last molar on the bottom left is "missing" leaving a hole and a jagged edge to one side of the tooth.

How important and vital is it that I replace it? And is it something that can wait awhile?

Answer
Hi Maka,
    Well, it sounds like you are due for a visit to the dentist! Fillings are either metal or plastic composite, but whichever they are, they are placed into the tooth when they are soft and then set up to become hard. Because of what we call "undercuts" - places where the preparation (hole) in your tooth is bigger underneath than it is on the surface - they become "locked" in place once they harden. This means that they cannot fall out unless one of two conditions are  met: either a piece of the tooth breaks off, or the tooth decays around the filling. The latter is far more common.
    The problem is that your tooth is normally covered with a hard material, enamel, which is resistant to decay. When a filling is placed, that is removed (usually because it was destroyed by tooth decay) and the filling substitutes for it. Once the filling is gone, the decay-producing bacteria have a wide open area through which to attack the tooth. This can take place in a very short period of time.
    So, bottom line is that you need to get the filling replaced as soon as possible. Otherwise the decay will get into the pulp or "nerve" of your tooth, and you will need root canal therapy or to have the tooth extracted. So, prevention is a lot easier and cheaper than waiting for that to occur.
    Sorry for the delay in answering - I was out of time at a meeting and couldn't get to my e-mail. Good luck!

Dr. Liewehr