A dental filling uses a dental restorative material which is used to restore the function, integrity and morphology of missing tooth structure. The structural loss typically results from tooth decay. Filing has three categories: amalgam, composite and GIC. a) An amalgam filling is a mixture of mercury and other metals like silver, tin or copper and it is contoured after placement in the tooth. b) Composite filling is made with ceramic particle mixed with a gel-like substance which gives the colour like a tooth. c) GIC filings is a mixture of minute glass particle with a gel-like substance which sets into the tooth within 5-10 minutes after it is applied.