There are three main types of fillings that are commonly used today.
1. Tooth Colored Fillings
2. Amalgam Filling
3. Cast Fillings
Tooth colored fillings, or white fillings as some people call them, are aesthetic fillings that are commonly used for restoring decayed or broken front teeth. There are different shades available to match the color of your teeth. Due to the constant improvements in the strength of the tooth colored fillings, more are being used for molars and premolars.
There are also different types of tooth colored fillings mainly composite resins and glass ionomer cement.
Amalgam filling, or common known as silver/black filling, is a metal based filling which contains silver, copper, tin and mercury. It is however important to note that the mercury content is of very small quantity and amalgam fillings have been used for more than a century with little problems. Amalgam is a good filling for posterior teeth because it is a very strong material able to stand high pressure and wear.
Cast fillings are usually used when the cavity is large with not much tooth structure left. They are usually made from gold or porcelain. As the tooth is weaker due to the large hole from the decay, cast fillings help to strengthen and support the tooth. But the cast filling have to be made in the dental laboratory before placing in the mouth so it will usually require 2 visits to complete the procedure.
The many fillings available today have different properties, so your dentist will have to assess the situation to determine which one is better for you.