Is flossing actually important or is it just dental industry messaging?

Flossing is clinically important, and the 2016 Associated Press story claiming there was "little evidence" for flossing was significantly overplayed in terms of its clinical implications. The story accurately reported that the clinical trial evidence for flossing specifically reducing cardiovascular events is not abundant, which is true. What it missed is that flossing reduces interproximal plaque biofilm, and interproximal plaque is the primary site of periodontal pocket formation. Reducing interproximal plaque through flossing reduces the bacterial load that produces gum disease. Reducing gum disease reduces bacteremia, hs-CRP elevation, and the cardiovascular downstream consequences.

The mechanism does not require a direct flossing-to-cardiac-outcome RCT to be clinically valid. It requires an understanding that periodontal biofilm between teeth is not reached by a toothbrush, that interproximal plaque is the predominant site of periodontal disease initiation, and that daily mechanical disruption of that biofilm through flossing or interdental brushing is the only home care tool available for that anatomical site. An electric toothbrush cleans buccal and lingual surfaces. It does not clean between teeth. Flossing is not theater. (Tonetti et al., Journal of Clinical Periodontology, 2018)

Cardiologist's calibrated position, Promising (2) for flossing as cardiovascular prevention, mediated through the periodontal disease reduction pathway.

What to do: Floss once daily, before brushing rather than after, so that loosened debris is cleared by brushing. If you have established periodontal disease, ask your hygienist about interdental brushes (proxabrushes), which are more effective than string floss for wider gaps created by bone loss.

For the full picture, read The Appointment You've Been Skipping Is Protecting Your Heart.