There are many products currently on the market that promise whiter, brighter teeth, many times overnight. But, dental professionals, and the American Dental Association, issue a word of caution about the improper use of such over-the-counter products, as they are often too abrasive and can damage the teeth with extended use.

Most will contend that there is nothing harmful about many teeth bleaching procedures, as long as they are dentist-supervised. In most supervised cases, teeth bleaching can effectively whiten and brighten the color of teeth for up to five years, without softening or weakening the teeth and gum line.

The dentist will use either an in-office bleaching system or laser bleaching while you are in the dental chair. Most patients, however, choose dentist-supervised at-home bleaching, which is more economical and, in most cases, provides the same results.

At-home bleaching involves using a custom-made mouthguard that can be worn comfortably while you are awake or sleeping. The mouthguard is so thin that you should even be able to talk and work while wearing it. Some bleaching systems recommend bleaching your teeth from two to four hours a day -- these usually take 3 to 6 weeks to complete and work best on patients with sensitive teeth. Other systems recommend bleaching your teeth at night, while you sleep, which may only take 10 to 14 days to complete.