Teeth whitening or dental bleaching is a common procedure in dentistry and is usually carried out by a registered dentist or dental nurse. It is one of the most common cosmetic procedures in the US, unsurprising when we consider that 99.7% of adults believe in the power of a smile in social settings. Whether for a job interview or a date, many people think that having an attractive smile can make all the difference. As there are many causes of teeth discolouration, there are also many methods of whitening and reasons for choosing procedures in the first place.
Adult teeth tend to be less white than baby or milk teeth. With age, adult teeth often become darker. In part this is due to changes in the mineral structure but the most significant factor tends to be the person's lifestyle and diet. Foods rich in carotenoids and xanthonoids can stain the teeth while the following foods, drinks and ingestible goods can also discolor teeth:
In-office teeth whitening: The safest way to have teeth whitened is at a dentist's office. The procedure will take several sessions, usually spread out over a couple of months. Although the whitening agents are some of the strongest, a dentist or dental nurse will first fit a mouth and gum guard which will protect the soft tissue from damage or burn from the whitening agents (usually carbamide peroxide, which breaks down to hydrogen peroxide – the 'bleach').
Light-accelerated bleaching uses light energy to quicken the effects of whitening agents. Laser whitening can be achieved in just one session. Halogen light is the most effective: it advances the hydrogen peroxide reaction. The effect of the lights is temporary. Most studies seem to indicate that around eight days after treatment, the effect on teeth is the same for those who have used the lights as those who have not – however, for those who are looking for a short-term and near-instant effect, laser whitening continues to be a popular choice.
There are countless at home teeth whitening products – ranging from gels, toothpastes and mouth washes to high concentration bleaching products similar in ingredients to those used by the dentist. Those with carbamide peroxide tend to come with application trays which distribute the whitening agent around the teeth. The danger with at-home kits is that mouth guards are not fitted to the person's individual mouth, which means that there is a greater chance of the agent coming into contact with and burning the soft tissue.
Possible risks of dental whitening include:
A treatment carried out by a dentist is less likely to result in the first two, where they will also be obligated to assist and treat the latter two. At-home kits or cosmetic treatments in a salon, etc., are more likely to carry these risks.
The nerve of the tooth is still growing until the age of sixteen. Bleaching can irritate the tooth nerve so bleaching is not recommended for those under sixteen years of age. Due to the agents involved, it is also not recommended for pregnant or lactating women.