Dentistry has undergone significant change over the past three decades, starting with the field's dramatic and unheardof success in periodontal disease. Nothing more than the teeth's colour reducing caries and can help one achieve a pleasing smile. Nowadays, dentists can frequently meet or even exceed such expectations by fully utilizing new materials and techniques. Due to social and psychological concerns, the patient places a lot of value on the tooth's colo ur. In fact, one of the main reasons a patient seeks cosmetic dental treatment is to have their teeth match the colour of their neighboring teeth. Tooth discoloration is a frequent issue. It can affect both primary and secondary teeth, and people of all ag es may be affected. Extrinsic and intrinsic factors can cause tooth discoloration. The most popular aesthetic procedure today for adults is bleaching. Bleaching is the process of reducing a tooth's colour by using chemicals to oxidize the organic pigmentat ion present in the tooth. It is obvious why bleaching has become so popular. Bleaching is the simplest, least invasive, and most affordable way to lighten discolored teeth and lessen and remove many stains in both vital and nonright pa vital teeth for the tient with careful diagnosis, case selection, and treatment planning and attention to the technique.