Composites have been in use for many years, mostly for aesthetic applications. The newest generations of composites have improved their chemical make-up so dramatically that the materials today can be used in many different applications, including the restoration of decay, closing undesirable spaces, improving the shape, size and color of a tooth, replacing an unsightly amalgam restoration, covering abraded or worn areas of a tooth (usually at the gum line) and to cover stains. Composites can also be used to protect thermally sensitive areas and to repair and strengthen broken teeth.