Tooth whitening: the science, the risks, the balance.

Posted on: 28 November 2015


Tooth whitening has become a popular form of cosmetic enhancement in this age of prioritising appearance and delaying the effects of aging on our bodies. Showing off a radiant white smile has been described as being "the fastest way to look younger", and tooth whitening products can help you achieve this. However, can you really know what these products are doing to your body? How do they work? What are the risks? And, at the end of the day, is it really worth it?

The Science

Yellowing of the teeth is an unfortunate but inevitable by-product of aging. There are said to be two forms of teeth staining: extrinsic and intrinsic. As the names suggest, extrinsic refers to discolouring that appears on the surface of the tooth, while intrinsic refers to discolouring that occurs between the cracks in the enamel of the tooth and in the layer below. Tooth whitening agents (opalescence gels) contain either carbamide peroxide or hydrogen peroxide, both of which act to permeate the enamel of your tooth to get at the discoloured molecules below. Oxygen molecules from the whitening product then react with the discoloured molecules, breaking them apart and resulting in a whiter, brighter tooth. The question then becomes: what sort of effect does this process have on the overall health of your mouths and bodies?

The Risks

Most people would recognise the scientific term "hydrogen peroxide" as being synonymous with bleach, a substance that you definitely do not want to be putting anywhere near your mouths. The Australian Material Safety Data Sheet on bleach recommends immediate medical attention if bleach is ingested. So why then should you feel okay about using tooth whitening products, whose active ingredient is often the very same poison you are warned away from? If applied properly, such products should only ever come in to contact with the enamel of the tooth, which is dead: thus the contention that whitening products weaken gums and teeth becomes void of persuasion. Additionally, the percentage of active chemical in the products is currently so low (0.1%) that scientists reviewing the product state that it could safely be raised to as high as 6%.

Now that you know the facts, you need to ask yourself: is it really worth it?

The Costs

Tooth whitening is not cheap. The process to achieve an effective, long-lasting white smile requires a visit to the dentist and fronting up with over $1000. However, committing to the formal procedure means that the results are likely to last for years, and will reduce the effects of staining through age. In the end, it comes down to personal judgment: if your confidence will dramatically increase knowing your smile is cleaner and brighter, the investment is probably worth it. If you just wish those years of drinking black tea every morning weren't quite so obvious, the money and time may be better spent elsewhere in your life.

Tooth whitening is a scientific process designed to slow the signs of aging in our mouths. Although the chemical reaction that occurs sounds dangerous, the minimal amounts of active ingredient and the application of the product to the tooth enamel avoids any potential harmful effects. Thus the main consideration becomes a balance between the cost of the procedure and the benefits of a whiter smile: something each individual will need to assess based on their own personal situation.