Rubin: At a loss over dental floss
Dentists believe strongly that when it comes to flossing, science should keep its mouth shut.
It’s been three weeks since Associated Press reporter Jeff Donn dropped a bombshell on the oral hygeine aisle at the drugstore.
In the absence of actual evidence that flossing prevents gum disease and tooth decay, Donn’s story said, the federal government has eliminated it from its list of Dietary Guidelines for Americans.
The story topped newscasts and made headlines from coast to coast. Any coast to any coast, really; at least one story ran in Jakarta, Indonesia.
The Floss-Industrial Complex — it’s a nearly $2 billion industry worldwide, with half of that in the U.S. —recoiled.
The 60-percent-or-more of Americans who don’t floss regularly grinned triumphantly.
Then, it would seem, everyone went back to doing exactly what they had done before, dental-health-wise.
Flossers flossed. Non-flossers non-flossed. And dentists continued to tell their patients to either keep it up or get started.
“If you talk to any dentist,” says Franklin practitioner Donald Zelazny, “it’s dental horse sense. Do you need to have some sort of study that proves every single thing?”
If you are the government, yes. It’s a rule: guidelines have to be based on scientific evidence.
If you are the dean of the dental school at the University of Detroit Mercy, no.
“They don’t do research,” says Mert Aksu, “on things that are common knowledge.”
Patients fail to ask
In keeping with the previous research favoring floss, the following assessment is not scientific:
Patients are barely curious enough to mention Flossgate to their dentists, let alone curse their wasted $1.99 and fling what’s left of a fresh package into the trash.
That’s based on conversations with a handful of dentists and one hygienist who says we can’t use her name, but that patients who don’t floss tend not to use toothpicks or anything else either and have nasty mouths.
“I had one patient who asked,” says Anthony Neely, chair of UDM’s periodentology and dental hygiene program.
“By itself,” Neely told him, “it’s not going to be sufficient to reduce inflammation.”
But along with fluoride toothpaste, he says, it’ll take a significant bite out of the problem.
“The potential harm I see” from the flurry of news stories, Neely says, “is people misinterpreting the lack of good information for the lack of any information.”
In other words, even if the floss fact-finding is flawed, floss functions fine.
Teeth tell all
The studies that specifically praise flossing have been scientifically sketchy: too brief, too small a sample, too absurd a regimen.
In one, children whose teeth were flossed by professionals every weekday for nearly two years had a 40-percent reduction in the risk of cavities. Unless you live next door to a hygienist, good luck with that.
AP’s Donn looked at recent reports that compared toothbrushing with the dynamic duo of brushing and flossing. Synopses included phrases like “a moderate to large potential for bias” and “the evidence for flossing is weak, very unreliable.”
But it’s a different view, say dentists, when you’re peering into someone’s mouth.
Neely points out that a toothbrush will clean the front, back and biting surface of teeth, but not between them, and something needs to.
Zelazny says when patients mislead dentists about how much they floss, teeth can tattle.
“Any dentist will see a cavity on one tooth and another tooth right where those two teeth touch,” he says. “You say you’re flossing? Um, no.”
So professionals will continue to believe in flossing, which — science be dashed — feels pretty darned good. They still have free samples to give away, and they have patience.
They expect a better study to come along and prove them right, and if it does, it’ll be as sweet as a visit from the tooth fairy.