How Teeth Whitening Works

A white smile makes teeth appear brighter and healthier, which in turn can boost a person’s self-esteem. Whitening treatments are designed to lighten stains on your tooth enamel and may be performed either in a dental office or at home using a product that has been recommended by your dentist or another dental professional. You may also wish to discuss other esthetic options, such as veneers or tooth-colored bonding materials, with your dental professional.

The most common type of whitening teeth whitening is known as bleaching, and it involves applying a whitening gel or a peroxide toothpaste to the surface of your teeth, which then reacts with the staining molecules (chromogens) to remove or at least lessen their color intensity. Most over-the-counter whitening products use hydrogen peroxide as the bleaching agent, but there are other whitening agents available, including carbamide peroxide. Many whitening products also contain abrasives to aid in the removal of extrinsic stains from the enamel surfaces of your teeth.

There are a number of things that can cause tooth discoloration, including aging changes to the core substance of your teeth (dentine) that make it naturally darker, consuming food and beverages that stain, and smoking. Generally, whitening is only effective on the natural teeth that are exposed to the mouth; therefore, crowns and fillings won’t respond to whitening and will remain their original color.

During your first visit, the dental team will take impressions of your teeth so that they can fabricate custom clear plastic trays for your at-home whitening treatment. The trays are filled with the whitening gel, and you are instructed to wear them at regular intervals over two to four weeks for 30 minutes to an hour per session. Many whitening products include light activation to speed up or enhance the results, and your dentist will advise you on the best method for your specific needs.

When the whitening treatment is complete, your dentist will review your results with you. They will use a shade guide to compare your current tooth color to the desired result and discuss whether you’ll need follow-up treatment, such as veneers or bonding materials, to achieve a completely white smile.

Some people’s whitening results will fade over time, depending on how often you consume foods and drinks that stain your teeth and the frequency of whitening treatments. However, you should be able to achieve a noticeable whitening of your teeth for several years, particularly if you avoid staining agents like coffee, tea and red wine. If you’re a smoker, your whitening effects will probably only last a year or so, but you can extend the life of your whitening by cutting back on tobacco use. You can also minimize the re-staining of your teeth by brushing and flossing regularly.