Background:

Despite being dentist-recommended since the early twentieth century, researchers have yet to conduct sufficient, reliable studies to support the claim that flossing effectively prevents cavities and gum disease.

Since doctors began saying that a string-based tooth scraping was good for oral health, a handful of studies have been conducted. However, they all fall far short of what’s needed to make a convincing argument. A 2011 review of a dozen randomized controlled studies concluded that, “Overall there is weak, very unreliable evidence which suggests that flossing plus toothbrushing may be associated with a small reduction in plaque at 1 or 3 months.”

Quote:

Still, many dentists will continue to recommend flossing for removing debris between your chompers. "It's low risk, low cost," National Institutes of Health dentist Tim Iafolla told CNBC. "We know there's a possibility that it works, so we feel comfortable telling people to go ahead and do it."

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