Tooth bleaching, also referred to as tooth whitening, is a cosmetic dentistry procedure of lightening and removing stains from a tooth. The teeth bleaching process involves bleaching the enamel and dentin and brightening the discolored teeth.

Tooth whitening or teeth bleaching are all the rage among those who value their looks. An attractive smile is like a neon sign announcing a youthful, pleasant and charming personality. It is also the key that opens up many doors. Not surprisingly, Hollywood stars and professional singers spend considerable amounts on tooth whitening/teeth bleaching procedures. Yellowed, stained teeth can spoil that important first impression, and even turn people off.

Small children have naturally white teeth than adults. However, our teeth’s mineral structure changes with age. Our habits can also influence the color of our teeth. Tobacco use can and does change the color of our teeth, as do bacterial pigments. In such cases, tooth whitening reverses the discoloration, restoring a dazzling smile. Sometimes, it is necessary to have tooth whitening done for health reasons. The discoloration may cause dental deterioration and the dentist therefore removes it on preventative grounds.

Tooth whitening is done by use of oxidizing agents like hydrogen peroxide or carbamide peroxide. These agent interact with the teeth’s enamel, oxidizing stain deposits much in the manner than bleaching agents whiten clothes. When done repeatedly, the bleaching action sinks lower and into the dentine layer. On completion, the tooth whitening process removes all signs of unsightly discoloration and the result is a dazzling white ‘ Hollywood smile’.

Dentists perform teeth bleaching in two ways. The ‘office bleach’ procedure involves applying a layer of the oxidizing agent onto the teeth. The dentist flushes away this layer after a short period, bringing instant tooth whitening results. The dentist usually uses a 35% hydrogen peroxide equivalent for this procedure. While it is certainly fast, using this method of tooth whitening is not entirely risk-free. The bleaching agent can damage the soft tissues because of chemical burns and the dentist must therefore supervise the process minutely.

The other method of teeth bleaching involves placing a thin strip of material that holds the bleaching agent directly onto the teeth. The dentist does not remove this strip in the same sitting. The patient retains it for periods ranging between a few hours to several days. Bleaching teeth by this method is not as convenient as the ‘office bleach’ method and obviously takes more time. However, many dentists advise their patients to opt for it rather than the ‘quick fix’ method. This is because this method of tooth whitening carries with it less risk of soft tissue damage.

Tooth whitening is not always successful in every patient. Some patients have yellowed teeth because they have been using certain medications such as tetracycline. This antibiotic causes stains that do not respond immediately to teeth whitening. In such cases, repeated teeth bleaching is required to penetrate the dentine layer and bring about the desired effects.

Newer procedures now involve the use of light to speed up the teeth whitening effect. Light-activated bleaching is still in its infancy and needs further study is required. However, the perfection of this new process can certainly revolutionize teeth whitening, making it a faster and safer process. Other areas that medical scientists need to address are the issues of chemical burns, sensitive teeth, overbleaching and premature loss of the whitening effect.

American Dental Association