Over time, our teeth become discolored. This can be attributed, but not limited, to coffee, red wine, tea, smoking and other nicotine related products. Professional bleaching whitens by applying a gel solution over the teeth, so that it is able to penetrate through the enamel and remove the intrinsic stains that have developed over time. Whitening may require maintenance and the frequency depends on your oral habits and diet. It is also important to know that whitening will not lighten bonding or veneers.