Teeth Whitening. Teeth can become discolored due to developmental defects, staining from food and drink, trauma, or as a natural result of aging. Many stains can be removed with a simple cleaning. If you have stained discolored teeth your dentist can help. It is important to know that veneers, crowns, and fillings will not improve with whitening treatment and may need to be replaced.
  For mild external stains, the best treatment is over the counter whitening products that you can purchase at most drug/grocery stores. These products are relatively inexpensive, produce little sensitivity, and can sufficiently lighten the teeth in certain cases. It is usually recommended that you try these products before you attempt other methods of whitening.
  If the over the counter products are not effective, the best treatment is to have a custom whitening tray frabricated at the dentist and to use a prescription whitening agent. Usually, long lasting results can be achieved within two weeks of daily, at home use. This method can often produce better, longer lasting results than the over the counter products, but is more costly and more likely to produce sensitivity.
  In office treatments involve application of a whitening agent for one hour or more in the dentist's office. This method can whiten more rapidly, but the affects are not as long lasting as those seen with the whitening trays. The biggest disadvantage of this method is the likelihood of sensitivity, which in some cases is severe.
  It is highly recommended that you begin using a sensitivity toothpaste daily for 3-4 weeks before you begin any type of whitening treatment in order to reduce the likelihood of sensitivity.