In a teeth whitening procedure, hydrogen peroxide is applied on the enamel of the teeth. A chemical reaction is produced, modifying the enamel protein configuration. This changes interfere with the way light reflect on the enamel surface. By reflecting more light, your teeth will be brighter and whiter. This process usually has a long-lasting result. 

Many techniques are available. They are equivalent in terms of outcomes. The only difference is the time of the treatment. Caution, smokers should avoid smoking during the treatment period since the cancer effects of cigarettes are stronger with the hydrogen peroxide application.