For decades, flossing has been a routine part of daily dental hygiene. It may not be all that pleasant, but it's effective at fighting the build-up of bacteria and plaque that can lead to tooth decay and even more unpleasant things.

Listerine, a mouth rinse manufactured by Pfizer, is now advertising its product as just as effective as flossing.

"It's clinically proven. A quick, easy rinse with Listerine Antiseptic twice a day is actually as effective as floss," the TV commercial states. Flashy animated graphics show streams of Listerine flowing around teeth, magically removing bits of food and plaque.

Can this be true? Can using a mouth rinse be as effective as cleaning your teeth with dental floss? Well, don't throw away your dental floss just yet.

Listerine's advertising claims are based on two studies conducted for the American Dental Association. The studies met ADA's scientific criteria for bona fide research, but it is worth noting that both studies were funded by Pfizer, the maker of Listerine.

The latest study showed that, among the test sample, ranging in age from 18 to 65, who suffered from mild to moderate gingivitis, Listerine Antiseptic mouth rinse, used twice daily as directed, reduced plaque between teeth by 20%, and gingivitis by 11%, after six months. The study showed that flossing reduced plaque by only 3.4% and gingivitis by 4.3% in the same period.

Surely, now we can toss the dental floss? Well, not quite yet.

The Listerine Web site, which echoes the claims made in the TV commercials, contains fine print that notes that Listerine is "not a replacement for floss." Really? You certainly don't get that impression from watching the commercial.

The Pfizer-funded ADA studies were of people with gingivitis, a mild form of gum disease that affects most American adults. In other words, the test sample was made up of people with normal, healthy gums and teeth. Those suffering from periodontitis, a more serious gun disease, need to floss daily to maintain good oral hygiene. Somehow, that subtly doesn't come across in a thirty-second spot.

A yet-to-be published, Pfizer-funded study shows even more dramatic results when test subjects brush regularly, floss daily and use Listerine twice a day. We can probably expect to see another round of TV commercials when that study is released.

For its part, the ADA says its position remains clear. For good dental health, it recommends twice daily brushing, daily flossing, and regular visits to the dentist.