Tooth whitening is a popular procedure, but it can be harmful

Fuelled by the desire for a perfect smile, the tooth whitening market has soared in recent years. There are now countless products available, like gum and toothpaste, as well as services offered by dentists, salons, spas and mall kiosks.

But concerns are being raised about the safety of some dental bleaching treatments and products. This is due to the unsupervised and undiagnosed bleaching procedures being undertaken by non-dental professionals, and the introduction of at-home bleaching.

"Teeth bleaching and whitening is a chemical procedure that can cause irreversible damage to human teeth if handled improperly," says Dr Alfred Yung, honorary secretary, Hong Kong Dental Association (HKDA). "Intra-oral treatment and dental procedures like tooth bleaching provided by non-dental or non-clinical professionals therefore pose a threat to the public health and should be banned."

In October, the European Union applied stricter rules to the sale and use of teeth whitening products. Based on advice from the European Scientific Committee on Consumer Safety, tooth whitening or bleaching products containing up to 0.1 per cent hydrogen peroxide - the active compound in whitening products - will continue to be freely available to consumers. Products with concentrations higher than 0.1 per cent, up to 6 per cent, will only be sold to dentists.

The General Dental Council, the organisation that regulates dental professionals in Britain, has since successfully prosecuted cases involving tooth-whitening companies or individuals who were not registered with it and who illegally carried out the business of dentistry.

The HKDA has also taken measures to further reinforce regulations governing tooth whitening treatment and the use of dental whitening products to eliminate unsupervised bleaching procedures in Hong Kong.