Two systems are the most common bleaching of teeth.

The first is managed by the patient at home applying the teeth masks in plastic soft reproducing the form of arches and containing a whitening gel that can oxidize substances colored responsible yellowing of. It needs clearer instructions and more days of application, from six to twenty or so, depending on the percentage of bleaching agent in the gel.
The second study is done in the dentist after having protected the gums apply the teeth whitening product and active through a special light plasma, laser or halogen. This procedure allows you to get a good aesthetic result in a single sitting.