What Factors Affect the
Color of Teeth?
    Some people are born with teeth that are more yellow than others. Others have teeth that yellow with age. Your natural tooth color can also be affected by many factors. Stains and discoloration can be caused by tobacco (whether smoked or chewed); drinking coffee, tea, or red wine; accumulation of tartar deposits; yellowing or graying of the teeth as part of the aging process and trauma.
What are Ways to Whiten Teeth?
    Thorough cleanings by a dentist or hygienist will remove most external staining caused by food and tobacco. Using a whitening toothpaste can also help remove these surface stains between dental visits. If stains have been present for years, you may need to have your teeth professionally whitened to remove these more stubborn external stains.
    Internal stains can be bleached, bonded or capped (crowned). While each of these methods is safe and
effective, your dentist will recomm-end which treatment is appropriate for you depending on the state of your teeth and the results you wish to achieve.
How Does Tooth
Whitening Work?
    Whitening (bleaching) can be done either in a dentist’s office or at home, using a system dispensed by your dentist. Both methods use tooth-bleaching gels that oxidize out the stain. It’s not uncommon for teeth to become slightly sensitive during the whitening process.
At-Home Whitening
    At-home whitening is the more popular approach today. Your dentist takes an impression of your teeth and makes a custom-fitted tray, which you fill with a whitening gel and wear up to two hours daily or at night for about two weeks. When done under the supervision of your dentist, at-home whitening is very effective.
In-Office Whitening
    Less frequent and more expensive, this procedure takes 30 minutes to one hour per visit, and you may have to return for several visits to achieve the desired whiteness. To protect your mouth, a gel-like substance may be applied to your gums, and a rubber “shield” may be placed around the necks of the teeth. An oxidizing agent (the bleaching solution) is then applied to your teeth. Sometimes, a special light is used at five-minute intervals to help activate the whitening agent.