Bleaching changes your natural tooth color by an average of five to seven tones. Whitening can be done both at the dentist's office and at home. The active ingredient contained in bleaches is usually composed of 10% to 22% carbamide peroxide or hydrogen peroxide, which helps to remove stains off the enamel.
Professional teeth whitening performed by dentists uses abrasion or polishing to remove external staining caused by food and tobacco. This process is not whitening. Both office and home bleaching have advantages and disadvantages.