Teeth naturally darken with age, and teeth can also be stained by certain foods and beverages such as coffee, tea, and wine. Smoking can also cause teeth to darken or stain.
Dental whitening is a procedure that removes stains from the surface of the teeth and also brightens the color of the teeth. Although there are teeth whitening products that are non-prescription and can be bought at your local drug store, the whitening effect will not be as strong as that of a professional in-office whitening. In-office whitening may also last longer than commercially available products.