Teeth whitening is one of the most requested procedures done these days in the dental office because it is a simple and painless process and that gives an aesthetic benefit in only one hour.
We have to keep in mind the reasons why teeth start to turn darker. The first reason is age, because you start to lose the enamel layer and the dentin makes the tooth look more yellow; the second reason is the metal and/or composite restorations. With time, metal starts to pigment the rest of the tooth a greyish color and the composite when turning porous starts to pigment because of the drinks and food we eat. The third reason would be that the tooth has a root canal which devitalizes it and turns it grayish; and lastly the external agents like tobacco, coffee, wine and other tinted foods.
There are two types of teeth whitening, the interior and the exterior; the interior whitening is only done when a tooth has lost its pulp (root canal) turning grayish. The exterior whitening is a procedure that is done the most because of its aesthetic purpose, here we use a 40% hydrogen peroxide based gel which is applied to the surface of the teeth in 2 intervals of 20 minutes each.
It is important to know that the only side effect produced by a teeth whitening is dental sensitivity, which can be controlled by desensitizers.
The cares after doing the whitening will help the result last for more time, therefore the patient must be aware that his diet and habits will be what contributes to this result.