What is bleaching?

Bleaching, you may or may not have seen advertisements on TV and in magazines about a readily available bleaching product marketed by a "celebrity" and some guy in a white coat. Always the way, no?

Professional bleaching products utilise a reducing agent, such as carbamide peroxide (non-professional bleaches the less effective hydrogen peroxide), to chemically remove stains. In order to this to work effectively, the bleaching agent - usually a gel - must be placed in close approximation with the surface to be bleached.

Before considering bleaching, your dentist will decide whether bleach will significantly change the colour of your teeth. Bleaching works best for superficial, surface staining caused by smoking and food/drink. Intrinsic staining, that is deep staining, will not bleach well and often patients are dissappointed with the result. However, the bleach cannot alter significantly the natural colour of your teeth. Tooth colour is dependent on a number of factors:

• Surface staining by food, drinks, nicotine - bleaching and polishing is very effective at removing these types of discolouration.
• Natural colour of enamel - enamel is translucent and it's natural colour differs depending the amount of flouride incorporated into enamel (often these are white specks), stained cracks and congenital defects (hypomineralisation, hypoplasia).
• Natural colour of dentine - as enamel is translucent, it is dentine that determines the colour of the tooth. Some individuals are born with yellow dentine and this translates into yellow-tinged teeth. Antibiotics such as tetracyclines can severely discolour dentine in developing teeth and should NOT be prescribed to children under the age of 12 if an alternative is present. Bleaches cannot affect dentine significantly in a "live" tooth.

Always consult a dental professional before bleaching your teeth.