MOUTHWASH is no substitute for dental floss. Some years ago in the United States, a federal judge ruled, calling a Listerine ad campaign false and misleading and a public health risk. Judge Denny Chin said in a written ruling that he expected to order Pfizer Inc. as soon as possible to stop claiming that its product, Listerine, is as effective as floss at reducing plaque and gingivitis between teeth.

The ruling came after Mc Neil-PPC Inc., a subsidiary of Johnson & Johnson, filed a lawsuit saying that false claims in the advertising campaign that began earlier posed an unfair threat against its sales of dental floss.

Now dentists and hygienists have been telling their patients for decades to floss daily. They have been doing so for good reason. The benefits of flossing are real – they are not a ‘myth.’ To say that the implicit message that a mouth rinse can replace flossing is false and misleading.

There is an ad in print which features a bottle of mouth rinse balanced on a scale opposite a floss container. This ad says: “This mouth rinse (name withheld) is clinically proven to be as effective as floss at reducing plaque and gingivitis between the teeth.” The campaign also featured a television commercial titled “Bing Bang.” The commercial announces that this mouth rinse is as effective as floss and that clinical tests prove it, though it does add that there is no replacement for flossing.

Substantial evidence demonstrates that flossing is important in reducing tooth decay and gum disease and that it cannot be replaced by rinsing with a mouthwash. Most related companies base their advertising campaign on emphasising that dental professionals should continue to recommend daily flossing and cautioned that they were not suggesting that mouth rinse should not be used instead of floss.

The judge said the company based its findings on two flawed studies of people with mild to moderate gingivitis who did not use floss properly. The studies, he added, proved only that Listerine is “as effective as improperly used floss.”

Gingivitis, which affects some two-thirds of the U.S. population, causes inflamed, swollen and sometimes bleeding gums. It can precede periodontitis, a less common inflammation that develops in deeper tissues and sometimes leads to tooth loss.

It should be noted that 87 percent of consumers floss either infrequently or not at all, despite frequent warnings from dentists and dental hygienists to do so. The judge said Pfizer had received complaints about its advertising, including one from a dental professional who said he was “aghast” to hear of the company’s claims and another who said the claims “can set back years of progress by the ethical dental profession in convincing patients that flossing is essential for their oral health.”

Flossing provides benefits that Listerine does not, including removing plaque below the gum line and dislocating pieces of food trapped between teeth. While Listerine is a powerful oral antiseptic, which clearly has its benefits, it could never replace dental floss. It is highly troubling that any mouth- rinse manufacturer would take the position that a mouth rinse can replace flossing.