Tooth whitening is a process of lightening (bleaching) the discolorations of your teeth. There are many reasons why teeth can become discolored over time. Certain foods and drinks, tobacco products, medications, systemic or chroNic illness and general aging. The main active ingredient of the product we use is carbamide peroxide, which releases oxygen into the dentin and enamel, causing the discolorations in your teeth to clear out of the teeth. Unfortunately, not all discolorations can be corrected through bleaching and the degree of whiteness after treatment can vary.