Teeth get stained over time by foods and drinks.  Think coffee, tea, red wine, beets – how much would they stain a white t-shirt?  Whitening uses a peroxide to clean those stains from the surface of the teeth.  We use KOR whitening in our office.  We prefer Kor because it starts with home treatments, and then finishes with in-office whitening and provides the best results.  We recommend a white diet after bleaching for 48 hours.  A list of non-staining foods will be given to you.  Whitening has no known long-term negative effects, but can result in some short-term sensitivity during treatment that will go away after your treatment is completed.