A Hollywood smile: Getting your teeth whitened

If you think your smile may be improved by whitening up your chompers, then don’t fret, you’re not alone. About one third of us think we could do with some brightening up in the tooth department.

Hollywood sure has made bright smiles famous, but actually, tooth whitening has been around since the late 1800s. From ‘back in the day’ to current times, the following bleaching agents have been trialled:

Chlorinated lime;
Oxalic acid;
Chlorine compounds and solutions;
Sodium peroxide;
Sodium hypochlorite;
Mixtures consisting of 25% hydrogen peroxide in 75% ether (pyrozone).

Nowadays, dentists generally employ the walking bleach technique, using a combination of 30% hydrogen peroxide and sodium perborate. Sodium perborate, hydrogen peroxide, and carbamide peroxide are the most common whitening agents today.

Power bleaching involves the dentist bleaching the outside of the tooth in the clinic. It often uses hydrogen peroxide.

The ‘tooth’ of the matter

Your dentist will work out what has caused the discolouration of your teeth to make sure you get the most appropriate treatment.

Tooth colour is determined by the colour of the dentine, enamel and any stains that may be on the tooth. A combination of these colours forms the overall colour of the tooth.

Discolouration: How did I get here!?

Don’t feel guilty – simply living your life normally can cause discolouration. For example, any of the following can lead to discoloured teeth:

Wine;
Coffee;
Tea;
Carrots;
Oranges;
Liquorice;
Chocolate;
Tobacco; or
Mouth rinses.

So, except for the last two, basically all the good stuff.

Discolouration that we can’t control

Certain causes of discolouration are beyond our control, such as:

Drug-related (tetracycline);
The way the tooth forms: Dystrophic calcification, fluorosis; and
Genetic: Congenital erythropoietic porphyria, amelogenesis imperfecta, and dentinogenesis imperfecta.

Other causes

Other causes related to problems or conditions inside the tooth include:

Death of the nerve;
Root canal treated teeth;
Fillings;
Resorption of teeth; and
An increase in the thickness of the dentine.

Possible side effects of bleaching

You may experience some tooth sensitivity or gum irritation, often because trays don’t fit perfectly. Or sometimes strong gels may be left on too long. Some people have also reported some jaw pain, a little ‘tooth movement’ or a sore throat.

Using a fluoride gel or sensitive toothpaste before you get your pearlies whitened may help with tooth sensitivity.

Be aware that whitening agents tent to negatively affect the look of existing fillings in the mouth. In general, dental fillings appear not to change colour at all, or as much as, surrounding teeth during the bleaching treatment.

Is a Hollywood smile for me?

Most people can have their teeth bleached, but not every case is guaranteed to have a successful outcome or be enough to make that person happy with the result. Your dentist will determine which form of bleaching is best for you.

Tooth whitening may be right for you if you have:

Generalised stains on your teeth;
Ageing teeth;
Smoking or dietary stains (such as from tea or coffee);
Dental fluorosis: Fluorosis with multiple spots on teeth may benefit from whitening;
Tetracycline staining: Not all cases of those who have suffered from tetracycline staining will be fully corrected, but many will improve dramatically; and
There have been changes inside your tooth (e.g. death of the nerve or root canal treatment).

Tooth whitening is not right for you if:

You expect a miracle to happen;
Your dentist tells you that you have decay in your mouth, gum disease, or infections under your teeth;
You are pregnant;
You have tooth sensitivity, cracks and exposed dentine – once treated, these teeth can be suitable for whitening;
You have existing crowns or large fillings in the smile zone – existing crowns or fillings that need to be changed following bleaching may be an indication that bleaching isn’t right for you due to costs; and
You are in the later years of life and have gum shrinkage and visible yellow roots.

Does it always work?

Tooth bleaching is successful in the research that has been done for it. Most importantly, it is inexpensive and less time consuming than other methods of making your teeth look whiter. It is estimated that 90% of people are successful in their whitening treatment.

It can be a little tricky to predict who will have the best results, but some of the factors include:

Age: younger people experience a greater reduction in yellowness immediately;
The type of bleaching done: Carbamide peroxide-based products stay active for a lot longer than hydrogen peroxide-based products;
The concentration of bleaching agent used: The higher the concentration of the agent, the more likely there will be side effects;
The amount of discolouration you have and the cause of the discolouration;
How much you decide to whiten you teeth at home: If you only whiten your teeth once a twice a month, there will be minimal improvement;
The design of the tray that is made for you; and
The number of bleaching treatments done and the time bleached for.

Also note that some people with staining due to tetracycline ingestion as an infant or toddler may require bleaching for several months before any noticeable change occurs.

Tooth whitening of teeth that are ‘alive’

Teeth that have a blood supply are said to be ‘alive’. Options include (click on table to view):

Non-vital whitening

Changes associated with the inside of the tooth can be a major cause of tooth discolouration. Trauma, previous root canal treatment and death of the nerve can all cause a tooth to become dark yellow, grey, or black. Non-vital teeth are those teeth that do not have a blood supply and have had a root canal treatment completed, or require a root canal treatment.

When bleaching those teeth with changes inside the tooth, options include (click on table to view):

Is it alright to go white?

The choice to whiten your teeth is entirely your own and now you know all the facts you can decide whether it may be for you. It is generally safe and very common, so if you feel you’d like to take the next step, just call up your dentist and talk about your options.

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