New study shows flossing may not be all it’s cracked up to be

For decades dentists have been telling patients to floss but what does the evidence say?

Flossing daily--Many dentists advocate for flossing

Flossing daily--Many dentists advocate for flossing

For many growing up, the advice to maintain good dental health was simple: brush and floss often. According to a report by the Associated Press that made headlines two weeks ago, the evidence supporting the need to floss is just not there.

Starting last year, the Associated Press asked the U.S. Departments of Health and Human Services and Agriculture for their evidence that flossing does in fact work. Further, they looked at rigorous research conducted over the past decade, focusing on 25 studies that generally compared the use of a toothbrush with the combination of toothbrush and flossing.

What they found was that the evidence for flossing is, “weak, very unreliable,” of, “very low” quality and carries, “a moderate to large potential for bias.”

Studies within their purview noted that there is little to no evidence that flossing is effective for plaque removal, with another study mentioning that flossing does lead to a slight reduction in gum inflammation, which can develop into gum disease if uncared for.

The Associated Press (AP) poked holes in studies conducted by the American Dental Association and the American Academy for Periodontology that proved flossing prevents buildup of plaque, early gum inflammation called gingivitis and tooth decay, noting that they used outdated testing methods such as testing for too short of duration or tested too few people to reach conclusive results.

Advice on the Canadian Dental Association website confirms that Canada too follows the convention of advocating for flossing, advising that Canadians should floss at least once a day.

“Flossing removes plaque and bacteria that you cannot reach with a toothbrush,” the website states. “If you don’t floss, you are missing more than one-third of your tooth surface.”

The Canadian Dental Hygienists Association notes that effectiveness in flossing mainly depends on the technique used in its ability to prevent gingivitis. In their notes, they point out that, “a lack of evidence does not mean (flossing is) not effective.”

The Association points out that although the revised 2015 Dietary Guidelines for Americans does not include a statement on flossing, this does not mean Canadian dental hygienists should change their evidence-based individualized approach to client care.

Karla Bliss, local owner of Columbia Dental Hygiene, supports the practice of maintaining flossing and says she still advises it to clients she sees everyday.

“Through my own clinical experience I can state that flossing is an effective way to remove plaque and food from in between teeth and by doing so you will reduce your risk for gum disease and cavities,” she said.

She said that it’s unfortunate that the mental dental research community is also an industry and it is therefore not surprising that they don’t have the time and resources to devote into a lengthy and expensive process to validate the use of floss.

“Similarly, you will be hard pressed to find research demonstrating the long term effectiveness of using shampoo to wash your hair, however it is an accepted part of our North American hygiene routine,” Bliss said.

The AP study did outline the need for more conclusive research to suggest flossing is effective.