Tooth Whitening Information

Tooth whitening, sometimes called tooth bleaching, is a safe procedure with over 40 years of clinical evidence. The first tooth whitening paper was published in 1989. The tooth whitening gel contains a form of peroxide, water, glycerol and flavouring and has a neutral pH. If you know of any allergy or have had an adverse reaction to any of these do not proceed with this treatment. Recent research confirms the safety of peroxides at the concentration used on the soft tissue – gums, cheeks, throat and tongue etc. The generally agreed ideal colour for your teeth is that they should match the whites of your eyes.

Discolouration of teeth has several causes. Many foods and drinks cause staining that ‘soaks in’ to the enamel and cannot be cleaned from the surface. The most common staining items are tea and coffee (the stronger taken the more staining), fruit and herbal teas, red wine, curries, soy sauce, mustard, tomato paste, colas, berries, beetroot to name a few!

Discolouration also occurs with natural ageing, the teeth look more yellow due to changes of the dentine inside the teeth.

Genetic factors – yes, some people do have naturally more yellow teeth than others and this will become more apparent through life.

Less obvious causes include various antibiotics particularly tetracyclines, and chlorine in swimming pools.

All of these discolourations do respond to whitening, sometimes difficult discolourations will take an increased concentration of peroxide or protracted wearing of the trays to get the colour desired.  There are a few documented cases where no colour change could be achieved.


Frequently Asked Questions

It is essential that you follow the instructions given by your dentist and the manufacturer’s instructions in wearing the trays and applying the whitening agent. Below are answers to the most frequently asked questions.

How long should I wear the trays for?

This depends on the amount of whitening that you desire and the original shade of the teeth. If you are not experiencing any sensitivity you may wear the trays for up to 60 minutes for day whitening and overnight for night whitening. It is important to remove all the excess whitening gel around the gums or palate prior to sleeping with the trays in. The darker the teeth, the longer they will take to lighten. Tetracycline teeth can take months to whiten, some teeth can take as little as 10 days.

If you cannot wear the trays for a few days because of your hectic schedule it does not matter. Whiten your teeth according to your own schedule. Some people put the trays in after dinner and wear them for an hour or so while watching TV or doing the dishes and then replenish the trays and sleep with them over night.

What do I do if I have sensitivity?

Tooth sensitivity is the most common side effect of home whitening and over 80% of people experience it to some degree. Most people suffer from sensitivity periodically without whitening their teeth. Sensitivity usually occurs at the necks of the teeth where the gums have receded or where there are existing cracks in the teeth. If you are experiencing sensitivity you should firstly try one day whitening and one day resting or you can reduce the time the trays are in your mouth, perhaps to an hour or so.  You can use the Pola Soothe gel dispensed in your kit or use Sensodyne Rapid or Colgate Pro-Relief topically or Tooth Mousse in your whitening tray for 1 hour. If you are concerned please contact the practice.

What happens if my teeth do not evenly whiten?

Teeth often have white spots that become more obvious during the early phases of whitening but tend to even up after longer periods of whitening. Occasionally deep white spots need a process called Microabrasion to become invisible. There is a product called Tooth Mousse that often fades white spots. Some teeth whiten more quickly than others, for example the thinner incisor teeth and then you can place the gel just in the parts of the tray corresponding to the darker teeth. The canine teeth are large and robust and tend to be more yellow and take longer to whiten.  The tips of the teeth whiten first and the gum line of the teeth will take longer.  If you have marked gum recession the roots of the teeth (made completely from yellower dentine) will be exposed and these may never whiten to the same colour as the rest of the teeth (there are procedures that can mask these areas if required). Some teeth can appear banded with lighter and darker areas during treatment. These areas were already present but become more obvious during treatment, after further whitening the colour will become more even.

How will my teeth feel?

Normally teeth feel very clean after whitening. The whitening procedure has an indirect beneficial effect on gum health. This is how whitening was discovered, from trying to improve gum health during Orthodontic treatment. Research shows that peroxide reduces the bacteria that cause decay also.

What about my smile?

Your smile will appear brighter, whiter and more youthful. Very occasionally teeth do not whiten. It is very important to follow instructions carefully. If the teeth have not whitened despite doing everything correctly there are different concentrations of gel or different techniques that can be tried.

If you have tooth-coloured fillings in your front teeth they may no longer match your new whiter shade. The fillings can be replaced or if healthy just refaced to match the new shade.  This is usually done 2 – 3 weeks after whitening to allow the new shade to fully settle. Crowns and veneers will not whiten.

How long does the whitening last?  Will I have to do it again?

Normally the whitening effect is long lasting. The exact length of time depends on the reason for the original discolouration and also your diet as regards staining foods and drinks. If you keep the trays safely you can top up with the odd night’s treatment as required. It is rare to need to repeat the whole procedure.

Does whitening harm teeth or gums?

Safety studies have shown that dentist-prescribed whitening techniques are perfectly safe in the mouth. The whitening material has a pH that is neutral. 'Over the counter' bleaching kits are usually inexpensive but often contain an acid rinse which can damage the enamel of your teeth. It is advisable not to whiten while smoking. It is advisable not to whiten during pregnancy or while breast feeding simply as there is no current research proving safety or risk in this regard. Whitening teeth is a simple, non-invasive way of rejuvenating your smile, is tried and tested over many years, highly researched and proved safe and effective.

Enjoy your new smile!