A gleaming white toothy grin is everybody's dream.
Responding to this desire, a range of whitening products is now available to consumers for use at home.
But the Consumer Council has this word of caution for the over-eager consumers: beware of the side effects of these whitening products.
A common side effect is that whitening can often cause tooth sensitivity or irritation to the gum.
Incorrect use of these products - using them for too long or too frequently - can only heighten these side effects.
As long-term data on their use are not yet available, consumers are therefore advised to consult a dentist before using tooth whitening products.
Tooth whitening products generally fall into two main types, namely the whitening toothpaste or tooth powder, and the peroxide-containing whitener or bleaching agent.
Whitening toothpastes usually contain special abrasives such as hydrated silica to improve tooth appearance by removing surface stains.
Tooth powders also contain abrasives but usually of a relatively more coarse type.
Long-term use of these products containing abrasives may result in roughened tooth surface which makes stains deposit more readily.
Peroxide-containing whiteners or bleaching agents are marketed in the form of whitening strips, whitening pens or whitening systems depending on the application method.
Most are formulated with hydrogen peroxide or carbamide peroxide with varying levels of concentration.
The Council has found 1 tooth whitening product to contain 6% hydrogen peroxide while another 6% carbamide peroxide.
According to the Department of Health, the use of these 2 products may cause irritation of mucous membranes in the oral cavity and in the gastric tract if swallowed accidentally. The risk is believed to increase with the frequency and amount of use.
The Department advised that members of public should consult dentist before use of tooth whitening products containing hydrogen peroxide.
Peroxide-containing whiteners are available from dentists or over-the-counter, ranging in price from approximately $200 to $250.
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