Bacteria in the mouth breaks down sugars we eat to produce an acid that causes dental caries (cavities). To prevent further progression of cavities, dentists remove the decay and restore the tooth with a filling. In our office, we restore the teeth with tooth colored resins. Resins allow the dentist to restore the tooth to a more natural appearance than amalgam, or metal fillings. Resins are also less prone to causing teeth to crack, are more conservative than amalgams, and unlike amalgams, do not release mercury.