Bleaching is big business. In 2004, Americans spent over $2 billion on tooth bleaching. Nearly $280 million of that was used on tooth bleaching at home in the form of tooth bleaching kits and tooth bleaching gels. That same year, one in five dental patients inquired about the dangers of tooth bleaching as compared to one in 10 dental patients who ask the same questions in 2001.

Our interest in tooth bleaching can be seen with the rapid growth in popularity of whitening toothpaste. But exponential growth is often followed with its own set of problems. Many patients who experiment with in-home tooth whitening experience what dentists call zingers. Zingers are an informal term used for sharp pains in the mouth that last for a short period of time but have a bad habit of returning with frequency. In a 2002 University of Southern California School of Dentistry survey of 100 people, approximately half of them experienced mild to moderate sensitivity after using over-the-counter strength tooth whitening gel. Many of the over-the-counter strength whitening gels contain the chemical carbamide peroxide, which used to be the only tooth whitening chemical approved by the American Dental Association. While the ADA now approves other chemicals or tooth bleaching, it is the use of these chemicals in the home which causes concern.

“There is much evidence that, when used as directed, bleaching does not cause permanent damage to teeth and gums,” says Edmond Hewlett, DDS, an associate professor at UCLA’s dental school. The dangers of unsupervised and abused tooth bleaching tend to be confined to the less serious, but side effects can include irritation of the gums, blue enamel, and in some cases, if the bleat is able to find its way into a crack in the tooth or a cavity, it can cause painful damage that must be fixed with a root canal.