Dentists to keep eye on teeth whitening

People who use teeth-whitening products without the supervision of a dentist risk looking “bizarre”, according to a dental expert.

Professor Laurie Walsh from the Australian Dental Association told AAP that because fillings and some teeth stains don’t respond to bleaching products, “you end up looking bizarre, that would be the nicest word to describe it”.

The warning follows a move by the consumer watchdog, the ACCC, to allow dentists to give patients stronger whitening products in take-home kits, effectively opening access to products from the US.

Under Australian laws, only dentists can use whitening products that contain more than six per cent hydrogen peroxide.

Teeth whitening is popular in Australia, with one-in-five people choosing to bleach, according to a 2020 Australian Dental Association survey of 25,000 people.

But the survey found that less than half did so under the supervision of a dentist.

Of those who whitened, 53 per cent used kits bought online, or from a supermarket or pharmacy, and almost 65 per cent of survey respondents said they were not aware of the risks of whitening their teeth without a dentist.

Professor Walsh said the risks of whitening products range from sensitive teeth, to chemical burns on cheeks and gums.

He said only dentists could manage these risks, and determine which patients would benefit from whitening products.

“Most people doing at-home whitening will have stains from their diet, such as tea or coffee, and that’s easily removed with a professional clean,” he said.

More than a third of respondents to the survey said they whitened their teeth about twice a year, and just over a quarter said they did so fortnightly.

A recent study led by the University of Toronto found teeth-whitening gels can halve the enamel protein content of teeth.

The study, published in Nature Scientific Reports in August, found a recommended application of 10 per cent carbamide peroxide gel on teeth reduces the enamel protein content by up to 50 per cent.

Carbamide peroxide gel at 35 per cent concentration can be purchased online.

A 2019 study from Stockton University in New Jersey found hydrogen peroxide breaks down the dentin protein found in teeth.