"Teeth whitening" refers to a number of procedures designed to enhance the brightness of the patient's teeth and the appearance of his smile. These techniques may include mild acid whitening, chemical whitening, abrasive teeth brightening and the more advanced technique, laser teeth whitening. Professional bleaching is the most common form of tooth whitening. This procedure can be performed in the dentist's office or at home using a teeth whitening kit. You can also choose to combine in-office and at-home systems for a more efficient result. Bleaching products contain an active ingredient, usually hydrogen peroxide or carbamide peroxide, that leads to a much lighter tooth colour by removing both deep and surface stains. Potential side-effects include a sore throat, tender gums and a minimal tooth sensitivity for a very short period of time. These symptoms should disappear in a few days. Be sure that your doctor supervises this treatment.