Intrinsic stains that are caused by damage to a nerve or blood vessel in a tooth sometimes can be prevented. You may need to have root canal treatment to remove the inner part of the tooth (the pulp) before it has a chance to decay and darken. However, teeth that have root canal treatment may darken anyway. To prevent intrinsic stains in children, avoid too much early exposure to fluorides.
Once the enamel is formed, fluoride will not discolor teeth.
Discoloration often can be removed by applying a bleaching agent to the enamel of the teeth. One technique is called "power bleaching." With this method, the dentist applies a light-activated bleaching gel. It causes the teeth to get significantly whiter in about 30 to 45 minutes. Several follow-up treatments may be needed, or take-home bleaching trays may be provided.
It's also possible to remove discoloration at home. You will use a bleaching gel and a mouth guard given to you by your dentist. The bleaching gels designed for use at home aren't as strong as those applied by your dentist. This means that the process takes longer — usually two to four weeks.
You also can buy whitening products over the counter. They contain a weaker bleach than the products you can get from your dentist. The whitening agent is applied as a gel placed in a mouthpiece or as a strip that sticks to your teeth. Over-the-counter mouthpieces fit less securely than the kind you get from your dentist.
Whitening toothpastes may remove minor stains. They do not actually change the overall color of your teeth.
If your tooth has darkened after a root canal, bleaching the enamel won't help. Your dentist can apply a bleaching material to the inside of the tooth, or you may consider a crown or veneer.
Bleaching will not lighten some stains, such as tetracycline stains. In this case, your dentist may recommend covering the discolored areas. This also may be useful when the tooth is chipped or badly damaged.
A tooth can be covered with a color-matched composite bonding material. Another option is to get veneers. These are thin ceramic shells that cover the outer surfaces of the teeth.
American Dental Association
211 E. Chicago Ave.
Chicago, IL 60611-2678