“The Australian Competition and Consumer Commission (ACCC) recently recalled a number of do-it-yourself (DIY) teeth whiteners containing unsafe concentrations of peroxide that can cause painful chemical burns, blisters and ulceration of the gums, mouth and throat.
“Consumers should be extremely cautious when using DIY teeth-whiteners, the ACCC warned, and check the product doesn’t exceed safe levels of bleaching agents (more than 6% hydrogen peroxide and 18% carbamide peroxide).
“So how do these products work? And why are some so risky?
“Tooth whitening attempts to make teeth appear whiter, usually by bleaching the surface enamel. The results can vary, from bright-white smiles to an almost non-existent change, depending on the original tooth colour, the cause of colour irregularities and the whitening technique used.
“There are four methods of tooth bleaching … , most of which use various concentrations of oxidising agents, such as hydrogen peroxide:
- Home bleaching – where low concentrations of bleach are applied using standard trays (which aren’t moulded to the patient’s mouth);
- Assisted bleaching in a dental surgery – to supplement to home bleaching with low-to-medium concentrations;
- Power bleaching in a dental surgery – the application of high concentrations of bleach and the use of a light to activate the hydrogen peroxide. Rubber dams and protective glasses are used to cover the patient’s face and eyes and;
- Over-the-counter products – which cover a variety of concentrations.
“Extrinsic stains – those on the outside of the tooth tissue caused by caffeine, tobacco and some bacterial pigments – can be removed by an oral health professional without bleaching.
“If you seek a whiter teeth, your choice of application and procedure will depend on the colour change that’s required (lower concentrations deliver more modest results) and how much you want to spend. But generally, you improve your chances of success if you visit a professional.