Royalty free and rights managed images of dental fillings. This dental treatment is used for cases of tooth decay (dental caries). Tooth decay is caused by the bacteria in plaque, a substance which covers the surface of unclean teeth. The bacteria break down sugar in the mouth, producing an acid which progressively destroys the teeth. Fillings are used to fill the spaces left when the decayed parts of the tooth are drilled away. Materials used for fillings include amalgam, glass cements and resins. Pictures and photographs include illustrations, dentists treating patients, and tooth X-rays.