How does tooth whitening work?
Whitening works by lightening the middle layer, also known as dentine, of our teeth. The hard outer coating of our teeth has small pores in it similar to our nose and the various peroxide bleaching gels (usually carbamide peroxide or hydrogen peroxide) release oxygen into the tooth structure, open these pores and draws the staining out from the layer underneath.
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Why does the tooth whitening result vary for different people?
If your teeth can absorb the oxygen well, the dark-coloured long-chain stain molecules are broken into short molecules. Teeth vary in how well they absorb the oxygen, which causes teeth whitening results to vary person-to-person. Stronger gels produce more oxygen which is why many people experience a different result with dental whitening as opposed to whitening solutions purchased ‘over-the-counter.’
Tooth stains that are caused by food and drink are organic and usually respond well to the whitening action of oxygen.
Stains that have been caused by too much fluoride or some of the antibiotics are inorganic and do not respond well to the oxygen. When you discuss tooth whitening with our dental staff they will give you a better idea of the potential results and also discuss your individual situation with you.
Our Take-Home teeth whitening method
A custom mouthpiece or “tray” is made to fit your teeth by Dr Zhang. This tray fits over the your teeth and in order to hold the bleaching material against your teeth for a specified period.
Different concentrations of bleach are then worn via the tray from as little as half an hour a day for an average of 10 to 14 days.
The treatment is determined by our dental team and may differ for each patient.
If the teeth become more sensitive to hot and cold, a “desensitising” material, like Tooth Mousse®, may be used in the same tray.
Results with this method are usually excellent.
How long will my teeth stay white?
Red wine, tea and coffee, and darker coloured foods (eg berries) are all examples of things which will affect your whitened smile. Smoking and age are also large contributing factors. We usually advise our patients that the result will last for 1 – 2 years, however we recommended that you touch up your smile every 6 – 12 months to prolong your white smile.
Most discolouration can be removed by bleaching which is a very conservative, safe and non-invasive approach to creating a brighter, more appealing smile.
It’s important, however, to have your teeth evaluated by your dentist to determine if you’re a good candidate for bleaching. There are some stains such as tetracycline and fluorosis, that are difficult to bleach, so other options, such as veneers or crowns may be more suitable for your situation.
Since teeth whitening only works on natural tooth enamel, it is important that we consider replacing your old fillings, crowns, etc. after the bleaching is done, your dentist can match the new restorations to the shade of the newly whitened teeth.
Is tooth whitening safe?
Research indicates that tooth whitening shows no changes to the surface of the teeth when bleaching solution is used. Therefore, there is no damage to the tooth whatsoever.
Is laser or light bleaching better?
We have tried and tested several market leading whitening systems – both with and without a light!
We have found our Take-Home Teeth Whitening method to be the safest and most effective way to lighten your teeth. By eliminating the need for a ‘light’ we can reduce sensitivity, damage to the tooth and gum, and also any false positive whitening results.
Laser whitening is different again to light whitening and is not as common. Most dentists that claim to do laser whitening are not actually using a laser, but the light machine. Unless you have purple or grey teeth where laser has an advantage, most people will get excellent results using our Take-Home teeth whitening procedures.
Are there any disadvantages to dental tooth whitening?
Dental tooth whitening is not a permanent whitening method and the result and time of result can vary between patients. Some patients also experience some discomfort due to the sensitivity of their teeth throughout the whitening process. This can vary and there are usually things we can do to minimise the discomfort of this feeling. We will discuss this with you at your whitening appointment.