Teeth whitening is a cosmetic dental procedure by which the tooth's surface colour is retained by removal of the dirt and debris, and the colour of the tooth surface is made a few shades whiter by use of dental bleaching agents.

Teeth whitening is a quick, non-invasive, and affordable form of treatment that enhances a smile.

Teeth bleaching can be professionally achieved in the dental office by the use of a special dental bleaching machine or dental laser and dental bleaching agents. Teeth bleaching can also be done using home bleach kits available at the local medical store.

Teeth bleaching gives you an enhanced whiteness and brightness of teeth. But it is not permanent and requires good maintenance and regular touch-ups for a prolonged effect.

Tooth staining happens due to several factors:-

• Age- As age progresses, there is a definite change in the colour of your teeth. Due to wear and tear, and stain accumulation teeth tend to get darker with age, and it is for the same reason that teeth bleaching in old age are more difficult to achieve and more time-consuming.
• Eating habits- Consumption of colour imparting foodstuff like coffee, tea, red wine, soft drinks, carrots, beetroot regularly causes staining of teeth over the years.
  Consumption of acidic foods like citrus fruits causes enamel erosion because of which the surface of the tooth becomes transparent, and the yellowish tinge of the dentin below can be seen. 
• Smoking- Nicotine leaves a brownish stain which is slowly absorbed by the tooth surface, causing an intrinsic stain.
• Use of certain drugs and chemicals- Tetracycline drug causes brown or dark grey stains, which are difficult to remove.
  Excessive consumption of fluoride leads to fluorosis, which causes white spots on teeth.
• Trauma- An injury or trauma to the tooth may lead to cracks in the tooth, which tend to be more prone to stain accumulation.
• Grinding- Grinding of teeth may leave micro-cracks in the teeth, which leads to the darkening of the biting edges.
• Natural tooth color- The natural tooth color may vary for different people. Generally, yellow-brown tooth color is more responsive to bleaching than a green-grey color.
• Translucency and thinness of teeth- While some teeth are translucent and thin, others are opaque and thick. The opaque and thick teeth appear lighter in color and are more responsive to bleaching.

Thinner and translucent teeth (more so in cases of front teeth) have less pigment necessary for bleaching.

Transparency of teeth cannot be corrected by any form of teeth whitening procedures.

A thorough dental examination is done by the dentist to check if you are the right candidate for teeth whitening, or if there is an underlying medical or dental problem causing your discoloration, that requires to be treated first rather than opting for teeth whitening.

The sensitivity of teeth or gums and the presence of certain fillings may prevent the use of certain products on your teeth. Your dentist will be the best person to guide you about alternative methods to whiten your teeth.

In people who have crowns and veneers in their mouth certain teeth whitening kits would be unsuitable as the peroxide in the kit does not penetrate the surface. Again, your dentist will guide you about the kinds of products to use for teeth whitening.