There are several different materials that can be used to fill a tooth that has a cavity. The location of the cavity plays a major role in determining which kind of material is best.
The most esthetic, tooth-colored filling material is resin composite. In most cases, this is the material of choice for fillings. We can blend the filling with your natural tooth for a seamless transition. However, composite can be very technique-sensitive, and in areas that extend below the gum line, it is not an ideal material.
Glass ionomer is a great option for cavities that extend beyond the gum line where controlling the area is difficult. It comes in a variety of shades that can be matched to your natural tooth; however, it does not bled well, making it better for non-esthetic areas. It also tends to wash out over time, so it is not the best long-term solution.
Amalgam fillings, also called silver fillings, are made up of a mixture of different metals. Although they're not esthetic, they are very long-lasting. Amalgam is an excellent material for fillings on back teeth where there are strong biting forces, where esthetics are not an issue, and when it may be difficult to isolate the area.
We don't place many amalgam fillings, but as long as they are in good condition, we don't recommend replacing amalgam fillings that you already have.