Can You Over-Whiten Your Teeth?

It is the belief, even a subconscious one, that, having whiter teeth makes us look younger, and indeed this is true to a large extent. There is however an element of caution perhaps to be introduced.

The process of whitening your teeth has become well established over the last decade or so and many ordinary people are enjoying beautifully white smiles that were once the preserve of those naturally gifted by nature or Hollywood stars who could afford to spend a fortune having all their teeth treated with sparkling white cosmetic porcelain veneers or crowns.

Everybody seemingly wants their teeth to look as white as possible, which is, I guess, as understandable as an old granny of 87 wanting stark white teeth on her new dentures. It is the belief, even a subconscious one, that, having whiter teeth makes us look younger, and indeed this is true to a large extent. There is however an element of caution perhaps to be introduced.

First of all, in terms of aesthetics, having super white teeth may not look natural or appropriate for the older person. Unless they have taken steps to have a complete facial makeover then extremely white teeth may draw attention and make the person seem slightly comical. Glaring white teeth, white hair, and indelible “crow’s feet” around the eyes could look a little spooky, or disconcerting.

Looking attractive is not just about having each and every feature text-book perfect but more about a completely integrated and natural appearance embodying symmetry in the face and features that are regular but not too pronounced.

We can certainly improve our appearance by means of modern technology and simple ploys but perhaps there are limits beyond which one shouldn’t go for fear of producing an unnatural result. Did Michael Jackson really do himself any favours by whitening his skin to the degree that he did? A change in one’s appearance, to be effective, should be subtle enough to fit in with one’s overall appearance and age perhaps.

There is another physical and practical reason why you might be unwise to seek to whiten your teeth to the ultimate degree, and that has to do with potential long-term harm to the teeth. Bleaching teeth is effective and safe in general; however it is not wise to subject the teeth to extremely concentrated bleaching gels for extended periods otherwise there is a danger of dessication of the pulp and possible damage in the longer term.

The pulp of a tooth is the bit in the centre commonly referred to as the “nerve”, and is in fact, a whole bunch of tiny nerve endings enmeshed with very small blood vessels. If the pulp is subjected to enough irritation, especially more than once, it may start to gradually die off since it has only limited powers of recovery from thermal, chemical, or osmotic irritation.

Strong bleaching gel that permeates well into the dentine of a tooth may cause too much irritation of a chemical or osmotic kind that could upset the pulp too much. In practice we do not know for sure what the safe limits are, but those who go for “power” whitening where a carbamide peroxide gel concentration of over 30% is used, enhanced with a halogen light for over 40 minutes, may be putting themselves more at risk.

The evidence suggests that the use of carbamide peroxide gels in concentrations of between 10-25%, however, is perfectly safe, and it is a shame that the EU has seen fit to try to preclude the use of these in home whitening kits. The alternatives to carbamide peroxide are sodium bicarbonate or peroxide which are fairly adequate for bleaching teeth but not generally quite as effective.

A whitening effect of up to 6 shades lighter is very effective in terms of improving one’s appearance and can be achieved quite easily with treatments from the dentist or home kits using bleaching agents of medium concentration. People attracted by the idea of achieving lightening of their teeth by up to 11 or 12 shades are either unrealistic in their expectations anyway or risking some long term ill effects. In the author’s opinion an improvement of about 3 shades lighter is absolutely ideal, giving a most pleasing, and importantly, a natural whiter appearance.