But what if flossing wasn't so important after all - what if it made no real difference to dental health?
That's the suggestion emerging from a new body of research.
Flossing is aimed at helping rid our mouths of bacteria. Just 1ml of saliva is thought to contain about 100 million microbes. The mouth is a warm, acidic environment that's perfect for them to flourish. While some of these bacteria are bad, turning food sugars into tooth-eroding acid, others actually prevent tooth decay by releasing chemicals that counteract harmful acid.
But the latest evidence suggests flossing has little impact on reducing tooth decay or preventing gum disease. British Dental Association researchers looked at the long-term effect in people who brush and floss and others who only brush, and found no difference in terms of reducing plaque, bleeding or subsequent gum disease.
A recent review in the Journal of Clinical Periodontology concluded that 'despite being widely advocated...the majority of available studies fail to demonstrate that flossing is generally effective in plaque removal and in reducing gingival (gum) inflammation'.
So although flossing may be good for removing food from between teeth, it's not successful in removing the biofilms causing problems. Researchers believe the best way to overcome biofilms and prevent tooth decay is to master your brushing technique.
They are confident that most people with normal teeth and normal gaps do not need to floss at all!