Teeth whitening is a cosmetic procedure used to make smile brighter. This is not a medical procedure and it doesn’t improve the quality and health of teeth. Only people with healthy gums and teeth without caries may go through the procedure.   

With age, the outer layer of enamel is worn away. This is the reason why the teeth may become darker. Some types of food and drink also have impact on enamel darkening: coffee, black tea, white and red wine, sport drinks, soda, strongly colored fruits, souses. Teeth become discolored also from smoking and taking some medications, like tetracycline. Any injuries and infections may worsen the teeth color.   

Persons used to whiten the teeth to improve the self-image. Most people are happy with the result.  

Two main types of teeth whitening are used:

• Bleaching removes surface and deeper stains of the tooth enamel. Carbamide peroxide is a chemical that is generally used to bleach the teeth.
• Whitening toothpastes are non-bleaching products and they remove only the surface stain of tooth. This is a relatively inexpensive way, but toothpaste brightens teeth only by one shade.
• Tooth whitening strips and gels are applied directly to the teeth. A person should use them once or twice per week for 10 to 14 days.  
• Whitening rinses take 12 weeks to achieve the result. A person should swill the mouth twice a day for 60 seconds.
• Mouthpiece strays allow having a maximal contact of the agent with the teeth surface.  

A dentist may bleach the teeth in the office or gives a patient the special kit to do it at home. For in-office bleaching, a dentist usually uses a stronger solution of peroxide (15% to 43%), while at-home solutions contain only 3% to 20% of peroxide. The dentist protects the gums with special gel or shield and put the mouthpieces on the teeth. The visit of teeth whitening lasts from 30 minutes to 1 hour. Regular visits may be needed as the results of the procedure may be not permanent. Soma factors, such as like smoking and coffee drinking, may speed the process.  

A patient also can buy over-the-counter (OTC) kit or take solution from the office. The dentist will explain how to use the product and how long to keep them on the teeth. OTCs are very similar, but a duration of keeping varies depend on the products.  OTC products are less expensive, but they don’t brighten the teeth as much as in-office bleaching solutions. To compare, in-office kits brighten the teeth by 8 shades, while the power of OTC products are only 2 shades.   

Bleaching doesn’t work when a patient has teeth with feeling, veneers, crowns, because the peroxide can’t affect the color of these materials. In some serious cases of discoloration, a dentist may offer veneers.  Patients with gum disease should contact with the dentist prior to using OTCs.

Teeth can become sensitive for short time. Mouthpieces may also hurt the gums. The whitening is not recommended to the pregnant woman and children under 16. If a person has an allergy to the whitening agents, the procedure can’t be carried out.