How can i do to whiten a tooth discoloration?

See a dentist: If it is a single tooth then you may have more treatment needs than you think. It may need a root canal and crown. If it is multiple teeth then simple whitening procedures can be done in office or take home. I recommend you see your dentist for treatment options.

Bleaching: Bleaching your teeth to change the color of the tooth enamel by removing stains. Your dentist can bleach your teeth at his or her office. The solutions used by the dentists have a concentrated peroxide solution of about 35%. During a single treatment, teeth can by whitened by 12 to 14 shades. You can also do it yourself with a kit you buy from the dentist using tray with bleaching material.

Bleaching: See your dentist so that the correct form of bleaching is used.