Teeth may lose their brilliant white appearance with time due to staining of the enamel and age. Dentin is the inner part of the tooth which becomes yellow with age leading to the yellow appearance of the tooth. Antibiotics such as tetracycline, fluorosis, silver fillings, amelogenesis imperfecta and even genetic factors can lead to yellowing of the teeth. Stains can also occur due to smoking, drinking tea, coffee or wine and accumulation of debris. In both cases, the white teeth begin to lose their luster. Therefore, teeth whitening has become the most preferred procedure in dentistry.
This is also known as in-office teeth whitening. Hydrogen peroxide gel or Carbamide peroxide gel is used for bleaching. The high-concentration gel is applied to the teeth by the dentist or a trained dental technician for 15-20 minutes at a time. The gums are protected by a rubber dam. The procedure is continued for an hour. The bleaching gel whitens the inner tissues of the teeth.
Custom made teeth whitening trays are also available. These are bleaching trays made of plastic resembling mouth guard. The tray contains low concentration peroxide gel which contacts the teeth when the tray is worn in the mouth. One needs to wear this tray for 2-3 hours every day to get the best results. Even though such trays are available in the stores, it is better to get custom made trays for perfect fitting.
Teeth Whitening Strips
Teeth whitening strips are thin flexible plastic strips which are available in medical stores. These strips contain peroxide gel for teeth whitening. The strips need to be applied to the teeth and kept for about 30 minutes every day for up to two weeks. The teeth remain white for a few months after which new strips must be applied.
Teeth whitening toothpaste
Teeth whitening toothpaste differs from conventional toothpaste because the concentration of hydrogen peroxide in such toothpaste is more than in normal toothpaste. These toothpaste remove the surface stains. The results are usually not apparent before weeks or months. This is a highly affordable option but not very effective.
A bleaching solution such as peroxide gel is applied evenly to the teeth. Gums are protected by rubber dam. The laser beam is then directed towards the teeth. The laser beam activates the gel present on the teeth which then whitens the teeth. This is a swift procedure for teeth whitening because the action of the bleaching solution is speeded up by the laser.
Contraindications for teeth whitening
The following conditions do not allow for teeth whitening.
- Bleaching cannot be performed in children aged 16 or less. This is because the enlarged pulp chamber in children at such an age becomes irritated by the procedure leading to sensitivity. Pregnant and lactating women also cannot undergo teeth-whitening procedure.
- People having gum diseases and worn-out enamel cannot undergo teeth-whitening. Presence of exposed tooth root is also a contraindication for teeth whitening.
- Sensitive teeth and gums make the person ineligible for tooth whitening. People allergic to peroxide must also not go for teeth whitening.
- Individuals having veneers, crowns, bridges and other dental restorations should not go for teeth whitening. This is because the restorations cannot be whitened which causes unevenness between the shades of the whitened teeth and the teeth with restorations.
Maintaining the whiteness
Avoiding smoking and food and drinks which stain the teeth helps in maintaining the white shine of the teeth. Brushing teeth at night apart from the morning with fluoride toothpaste is also effective in preserving the whiteness.