In the dazzlingly bright world of dental aesthetics, a place where people with even, white teeth are always smiling, there can only be one thing worse than unsightly yellow gnashers and that's weeping mouth sores. Yesterday, the president of the British Academy of Cosmetic Dentistry warned that super-strength home teeth-whitening kits, which can be bought over the internet, sometimes containing up to 250 times the legal limit of hydrogen peroxide, can cause mouth ulcers and burns.
In this country, shops can't sell kits with a hydrogen peroxide concentration above 0.1% but, for noticeable results, the concentration needs to be at least 3.6%, and therefore should be applied, or prescribed, by a dentist (it also means that anything you buy over the counter here probably won't work). "Getting a high concentration of hydrogen peroxide on your gums can damage the tissue but you also need to watch out for kits that are too acidic," says Dr Wyman Chan, founder of Smile Studio, the UK's first dedicated teeth-whitening clinics. "Almost all whitening products you can buy in this country are too acidic, which damages teeth by removing calcium and eroding the enamel. If you want to whiten your teeth, only go to your dentist. Their products won't damage your teeth and they will show you how to use them properly."
White teeth don't come cheap - home treatments at Smile Studio (moulds are taken of your teeth and made into trays, which you fill with gel and wear upwards of half an hour a day) start at £150. An hour-long whitening treatment costs £450. "But your teeth are one thing you don't want to scrimp on," says Chan. Nobody likes a cheapskate, even if they do have weirdly white teeth. And especially if they have weeping sores.