A dentist in Bay Roberts says keep on flossing, even though an Associated Press (AP) report out of the United States has questioned its value.

The AP news agency looked at 25 studies into brushing and flossing, and concluded the evidence for flossing is "weak" and "unreliable."

The investigation was prompted by the latest Dietary Guidelines for Americans, published in 2015, which no longer recommends flossing.

Dr. Michelle Zwicker is a partner at the Bay Roberts Dental Health Centre and is on the executive of the Newfoundland and Labrador Dental Association.

"I guess I was just perhaps a little bit disappointed in how it was presented," she told the St. John's Morning Show on Friday.

"The U.S. Department of Health dropping the recommendations really has very little to do with the benefits of flossing and more to do with the lack of predictable and relevant data."

The data is weak, Zwicker agreed, but flossing is hard to study scientifically because there are so many variables that could influence the outcome.

Getting a large enough number of people to commit to daily flossing would be a challenge for any study, she said. Another problem is that people don't always floss correctly.

Zwicker said even without the science, dentists feel it is important to educate people about how to look after their teeth and gums.

"The point is that cleaning in between your teeth is important." she said, adding there are many different ways you can do it — using toothpicks and other devices.

"There are lots of things that we recommend every day," Zwicker said. "We know the science behind flossing. It's just hard to prove it."

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