Tooth whitening What is it? Professional or do-it-yourself procedure to make teeth whiter.

Timings May take several weeks with repeated treatments to get best results, especially with home treatments. Should last 6-12 months or more, and may need top-up treatments.

Cost Home kit from 50. Professional whitening from 40 for a single tooth, to 500+ for the whole mouth.

What is tooth whitening? Teeth can be whitened by a dentist, over one to two appointments. Alternatively you can use a do-it-yourself whitening kit at home, either under the supervision of your dentist or on your own.

What tooth whitening can do. Results can never be guaranteed, and the best effects are found on teeth which have yellowed with age.

What tooth whitening can’t do. Whitening won’t alter the colour of fillings, crowns or any other dental work, or the roots of teeth that have become exposed as gums recede. You may have to have old dental work replaced to match your whitened teeth. Teeth that have stains or grey marks caused by childhood use of the antibiotic tetracycline are harder to whiten and the results may be poor.

What happens during treatment? The dentist makes a mould of your teeth, or you can make your own mould from a kit if you are doing the whitening on your own. Small amounts of whitening gel are put into the mould, which is soft and comfortable to wear. You fit the mould over your teeth and keep it in place. How long you’ll need to wear the mould depends on the product, and ranges from 30 minutes to overnight. Achieving the right level of whiteness can take repeated treatments over three or four weeks. Professional whitening, done by a dentist, is quicker because it uses stronger bleaches and the effect is speeded up with special lights. After treatment the colour of your teeth is permanently altered. To avoid treated teeth becoming stained again, you should avoid smoking and steer clear of strongly coloured drinks, such as red wine, espresso coffee and cranberry juice.

Results Teeth can improve over one to two treatments, but most people need repeated treatments over weeks or even months to get the best results. Effects should last from six months to one year or more. You’ll probably need occasional top-ups.

Risks Repeated bleaching near silver-coloured (amalgam) fillings can make teeth develop a greenish colour around the filling. Front teeth that are very thin or nearly transparent may turn darker with bleaching, and you should consult a dentist before using any home treatment. Bleaching tends to make gums and teeth more sensitive. This can be treated with de-sensitising toothpastes.

Where to get treatment If you are planning to whiten your teeth by yourself, it’s advisable to consult a dentist first, to make sure there are no potential problems. Many dentists offer tooth whitening, but you may prefer to find a cosmetic dentist who specialises in this treatment.

Cost Home whitening kits cost from 50. If teeth are whitened by a dentist, expect to pay around 40 for a single tooth, or up to 500 or more for the whole mouth.

Improving tooth colour without whitening Avoid strongly coloured foods and drinks. Give up smoking. Use whitening toothpastes.

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