Composite is a soft plastic material which is hardened by applying a blue light something like an ultraviolet light.

Composite is one of the more attractive options for fillings, and is the treatment of choice for small and first-time fillings. It has lots of advantages, including minimal need for tooth preparation, the ability to strengthen teeth and, most of all, aesthetic appeal.

On the minus side, it’s moisture-intolerant during placement, often takes longer to place than amalgam fillings, and has a shorter lifespan than other materials. Composite fillings may need buffing or replacing after two to five years, and are susceptible to coffee and tea stains. Some people also develop a sensitivity to cold in the filled tooth or have problems with food packing between teeth because of loose contacts.

See also bonding.