Teeth whitening is an increasingly popular cosmetic dental treatment, as it is fast, relatively affordable and can prove to be a huge boost to self-confidence due to the excellent results than can be achieved. However some people can find these results are shorter lived than expected. This is due to a common side effect, especially amongst those choosing laser whitening as the process can cause tooth dehydration.
The effect of tooth dehydration is that teeth can appear whiter than they really are, an illusion that quickly disappears as the teeth rehydrate. This can be pretty disappointing to see the initial effects disappear in just a few days. But why does this occur?
The reason teeth are more likely to dehydrate during laser whitening is because the laser is a source of high intensity light. It works by effectively boiling away the bleach from the surface of the tooth, causing some of the bleach to be absorbed by the tooth, resulting in it becoming whiter.
When the light is shone onto the tooth, it is absorbed by the darker areas of the tooth, while the lighter areas are more likely to reflect the light back. Any light that is absorbed is converted into heat energy. The areas of the tooth that tend to be the darkest are the pulp and dentin areas which are located inside the tooth, so these areas can end up becoming quite warm from the laser whitening.
The end result is that these warmer, darker internal areas will expand. As the pressure builds up the fluids contained in these areas will be pushed out though the porous surface of the tooth, leading to the tooth becoming dehydrated.
Increased Tooth Sensitivity
One of the problems that can arise from tooth dehydration is increased sensitivity. Sometimes this can be felt during the actual treatment. Teeth take two or three days to rehydrate, absorbing fluids through saliva, reducing any sensitivity. There is nothing that can be done about this darkening effect, and it is better for the health of the tooth if it is properly hydrated as dehydration can increase the risk of fractures.
Reducing the Risk of Tooth Sensitivity
Quite a few people have some degree of increased tooth sensitivity either during or after teeth whitening. For most the feeling is purely temporary, but It can be quite uncomfortable. One way of reducing this risk is to make sure your mouth is perfectly healthy before using any bleaching products, and to have a check-up with your dentist.
The reason sensitivity occurs is due to the many tiny tubules located in the dentin. If the dentin is exposed, then any substances will be able to enter the tubules that lead directly to the pulp area of the tooth. This is where all the nerves of the tooth are located, hence the reason for the pain. Using toothpaste specially designed for sensitive teeth will help to lessen sensitivity, as it works by gradually blocking up these tubules.
If you do suffer from sensitive teeth then it could be worth choosing a slower and gentler method of teeth whitening that is easier to control.