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  • Updated:1 Jan 2005

03.The causes of stained teeth

The natural colour of people’s teeth varies from white to yellow, with every shade in between. All teeth contain red and grey colours, and the grey colours increase with age.

Teeth are made up of three layers: tough outer enamel, softer dentine, and the inner pulp. As you get older, the enamel thins through wear and tear, and the darker dentine layer can begin to show through. The dentine structure also changes as it takes up more minerals from the pulp. These two processes can make older teeth appear yellow.

In addition to genes and aging, tooth colour depends on many factors, of which general health (when your teeth are forming) and diet and lifestyle (once teeth are in your mouth) are key.

  • Health: Your health — particularly in early years when teeth are still developing — can be responsible for intrinsic stains, which affect the colour of the tooth itself. Certain antibiotic drugs, such as tetracycline, can affect tooth colour during development, as can severe fevers. Damage to the forming tooth can also cause internal discolouration, as can damage to the pulp of a permanent tooth (as a result of receiving a blow during contact sport, for example).
  • Diet and lifestyle: Then there are the surface stains, caused by diet and lifestyle — tea, coffee and smoking are three of the biggest culprits.
    Stain removal

Many whitening products specifically refer to surface stain removal as one of their methods of whitening action. A professional clean at the dentist can also remove surface stains (including those between the teeth), often producing a fresher, whiter appearance.

But while removing surface stains can restore teeth to their natural colour, this doesn’t necessarily mean your teeth will be intrinsically whitened. Deeper stains are more difficult to remove and may not respond well to home bleaching treatments, or even to the special bleaches and whitening treatments used by dentists. If the tooth is very badly stained, some type of veneer might be needed to disguise the area.

So before you spend money on DIY whitening, it’s probably worth speaking to your dentist first about treatment options for the particular type of stain affecting your teeth.


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