Tooth whitening policy Tooth whitening can be a highly effective way of lightening the colour of the natural teeth without removing any of the tooth surfaces. It does not work on dentures, crowns, white fillings or bridges. The active ingredient in tooth whitening products is usually hydrogen peroxide or carbamide peroxide. As this active ingredient is broken down oxygen gets into the enamel on the teeth and the tooth colour is made lighter. In accordance with EU law, over the counter home whitening kits in the UK contain too little hydrogen peroxide (0.1%) to noticeably lighten the teeth. The legal limit for a dentist to use is between 0.1% and 6% hydrogen peroxide. These higher percentage products used by a dental professional will produce a safe, effective and long-lasting tooth lightening result. The first treatment should be carried out by the dentist (or hygienist or therapist on the instruction of the dentist), after this the patient can continue the treatment at home. Tooth whitening should not be carried out on anyone under the age of 18 years old. It is illegal for anyone other than dentists or their teams to carry out tooth whitening. Anyone else such as, salons, beauticians and pop-up booths, do not have the correct training or knowledge. They could permanently damage your teeth and gums and will not know how to treat you should something go wrong. It is possible to purchase tooth whitening products over the Internet. However many of these products contain many times over the legal limit of hydrogen peroxide which can result in extreme sensitivity, burned gums and/or blistered lips or even permanent damage to the enamel of the teeth. Many of the non-peroxide solutions that are used or supplied by beauticians and other illegal providers will not have gone through the rigorous safety and efficacy checks that a dental material will have gone through. Therefore any lightening effect is likely to be short-term. The Oral Health Foundation recommends speaking to your dentist if you are interested in having your teeth whitened. They will be able to check your mouth and assess whether you are suitable for the treatment. Then they will choose the correct solution to achieve the desired result.