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For seekers of physical perfection who live by the slogan, "You can never be too thin," there's a new one to chew on: "Your teeth can never be too white."
Some are taking the attainment of white teeth to the extreme by exclusively -- and excessively -- using over-the-counter teeth-whitening products.
The most widely used of these over-the counter products are whitening strips and a tray-based technique, in which a plastic tray, containing a bleaching gel, fits over a person's teeth and is worn for part of the day.
Some experts are reluctant to call this mania an addiction. "No, it is not possible to become addicted to teeth-whitening agents," says Robert Gerlach, DDS. Gerlach is principal scientist for worldwide clinical investigations at Procter & Gamble, the maker of Crest Whitestrips.
Others acknowledge that people are often guilty of overusing over-the-counter teeth-whitening products. How does this fixation start and what are the consequences?
What Motivates Overuse
For some, it's a narcissistic compulsion to maintain their youth, analogous to going for repeated plastic surgery, says Richard Frances, MD, an addiction expert and a clinical professor of psychiatry at New York University Medical School. "People are obsessed with the idea of perfecting their bodies and warding off the effects of age," he says.
Matthew Messina, DDS, a dentist in private practice in Cleveland and a spokesman for the American Dental Association, says television makeover programs have had a tremendous influence in making people see how an investment in their smile was also an investment in self-confidence. But this awareness, he says, "can be obsessive if we become hyperfixated."
"People are looking for anything they can get their hands on that can improve every part of the way they look, every advantage possible to one-up the next person" says James H. Doundoulakis, DMD. Doundoulakis has a cosmetic dentistry practice in New York and is the co-author of The Perfect Smile: The Complete Guide to Cosmetic Dentistry.
"Because of New York's competitive nature," Doundoulakis says, "you need all the tools - and one of them is that smile, which not only shows you're confident but that you're healthy and you have energy."
The Warning Signs of Overuse
While Messina underscores that "tooth whitening is a very safe and effective technique when done according to the product manufacturer's instructions and under the recommendations of a dentist," some people are after more than that. The warning sign for Messina is when patients "look for changes in their teeth to correct other issues and problems that have nothing to do with their teeth," such as improving their social lives or getting a better job.
Messina says that even a little bit of overuse of an over-the-counter whitening agent "is not going to do any long-term damage. The reason, he says, is "the safety margins for over-the-counter products is pretty large."
Doundoulakis, however, has seen people who have overdone the process. "The ones I have seen are getting results but their teeth are beyond snow white, they're like Clorox-white," he says. "They just want to keep doing it. They're going to keep doing it until those teeth are almost transparent."
Doundoulakis says they also might wind up with a root canal problem. He concedes that sometimes patients like these are unable to register that their teeth are already quite white. "They like the process of whitening," he says.
Messina has also observed patients whose dedication to regular whitening takes on a "more ritualistic" tone.
Can Teeth Be Damaged?
Richard M. Lichtenthal, DDS, says over-the-counter products are "not quite as strong in their bleaching activity, but there are people who will not follow manufacturer's instructions, and so the process can be abused."
Lichtenthal is in private practice in New York and is also chairman of a section of adult dentistry at the Columbia University School of Dentistry. He says overuse may cause sensitivity of the teeth, although "it will be very unlikely that damage to the surface of the tooth will be caused before the sensitivity occurs."
"When the teeth become sensitive, generally, people will stop using it," Lichtenthal says.
Some of the damage may be financial. Over-the-counter products may not be a bargain in the long run.
Because the bleaching material in over-the-counter products are weaker than the product one may obtain in a dentist's office, it's reasonable to assume that consumers may need more of it, and that this might contribute to overuse. The results may not be what the consumer had hoped for either.
"There's no assurance people will have achieved the results they're looking for," says Steven David, DMD, a dentist in private practice in New York.
David is also a clinical professor of cariology and operative dentistry at New York University School of Dentistry. "It's possible to spend the same amount of money without the monitoring of a trained professional," he says. According to David, that's the difference between buying a product and buying a service. "Dentists perform a service, and it's important for dentists to monitor the service."
Special Dangers for Younger Users
Lichtenthal does not recommend bleaching for people under age 18. "There's an increased risk that those teeth will become hypersensitive and the teeth's pulp will react with the bleach," he says. "The problem with bleaching younger children's teeth is the size of the pulp. The nerve inside the tooth is very large -- it hasn't shrunk yet."
Dentists would use X-rays to see how wide and how large the pulp is, he says. "That's a discussion the practitioner would have with the kid's parents."
If teenagers have part-time jobs, they may buy over-the-counter whitening products without telling their parents. "You have to know your own children," says Messina. "If your children are hyperaware of their teeth, it's not a dental problem, it becomes a psychological problem."
Messina believes it's the parents' obligation to advise their children about what's appropriate. "I think that's part of normal parenting -- to help your kids develop a healthy understanding of how they're going to make their way in an adult world. If parents have any doubts or worries, they should talk to their health professional."
Work With Your Dentist
One of the best reasons to include dentists in any whitening process is they know more than the patient and can help explain the fine points and limitations of the procedure. "Some people are bleaching, but those teeth are impossible to bleach," says Doundoulakis. Old fillings, old crowns, or decay in teeth will not take to whitening, he says.
"Partner with your dentist to discuss what you're trying to achieve, pick his brains and get his best recommendations on what products would be best and get the right direction," says Doundoulakis, who is director of implant prosthetics at New York's Mount Sinai Medical Center.
"Many dentists recommend over-the-counter products first," he says. A spokesman for Procter & Gamble and Crest, Doundoulakis sells professional-strength Crest Whitestrips, which Crest makes available for sale only through dentists' offices. He has also quelled the teeth-whitening mania of some of his more avid patients. "Once you lead them in the right direction, they can be reasoned with."
"The amount of product the patient has should be controlled by the dentist," says David. He concedes that it's not uncommon for patients to request a whiter shade than the one he suggests. "I'm obligated to tell them the truth - we'll get them to the whitest normal shade," he says. "If they want to go beyond that, they've come to the wrong office."
SOURCES: Richard Frances, MD, clinical professor of psychiatry, New York University Medical School. Matthew Messina, DDS, spokesman, American Dental Association. James H. Doundoulakis, DMD, director, Implant Prosthetics, Mount Sinai Medical Center; spokesman for Procter & Gamble and Crest. Richard M. Lichtenthal, DDS, chairman of a section of adult dentistry, Columbia University School of Dentistry. Steven David, DMD, clinical professor, cariology and operative dentistry, New York University School of Dentistry. Robert Gerlach, DDS, MPH, principal scientist, Worldwide Clinical Investigations, Procter & Gamble.