Dentin is yellow in color. As the enamel wears down, cracks in it begin to fill with debris, causing a dull, yellowish appearance. There are two types of tooth stains: extrinsic and intrinsic. Extrinsic stains are stains on the surface of the tooth. These stains are caused by exposure to wear and tear and certain foods and beverages.

Minor extrinsic stains can be removed through brushing regularly. Major stains may need whitening. Some penetrate through to the dentin. Intrinsic stains form on the tooth's interior through trauma or aging. Deep intrinsic stains can be managed through bleaching or an extensive whitening treatment. Many common reasons for stains on teeth are aging, the natural color of our teeth, eating habits, smoking, grinding, or trauma.

Solutions to deal with this problem involve some form of teeth whitening. There are a variety of options to choose from. They fall into two categories: one called, aptly named, "whitening", and the other called "bleaching". Bleaching involves, obviously, products containing some form of bleach commonly hydrogen peroxide.

There are three teeth whitening options currently available for the general public:In-office whitening offers the fastest results. The gums are protected with a paint-on rubber dam. A dentist or trained technician applies a highly concentrated peroxide gel to the teeth. This gel remains on the teeth, typically, for 15-20 minute sessions, adding up to an hour. If a patient's teeth are particularly badly stained, they may be advised to return for another treatment, or to apply a take-home whitening system to their teeth.

Professional take-home whitening kits, such as the ones offered in the previous scenario, employ lower-concentration gels that are applied through a tray resembling a mouth guard. Depending on the concentration, the gel is then left on the teeth anywhere from an hour to overnight. These systems are generally considered to be the most effective long-term solutions.

Over-the-counter whitening kits are the most convenient, however, they can be rather limiting. Teeth whitening gel is applied to the teeth in some cases, just the front teeth using trays, strips, or paint-on applicators, rather than custom trays designed to fit your teeth. They are the cheapest option for teeth whitening, however they can take the longest to produce results.

Bleaching can also be administered either in-office or at home. In-office bleaching employs hydrogen peroxide of various concentrations, while at-home bleaching solutions use carbamide peroxide, which is a weaker application. These are powerful teeth whitening solutions.

There are a few risks involved with teeth whitening, including increased sensitivity and gum irritation, both of which are generally temporary. However, if your teeth are bleached and you have some form of tooth restoration, such as crowns or veneers, they retain their original color while the teeth around it are whitened. This is commonly referred to as "Technicolor teeth".

Teeth whitening and bleaching are great ways to improve the look of your smile. When properly done, the process yields a natural, whiter smile that you can be proud of.