Historical perspectives on advertising and the meme that personal oral hygiene prevents dental caries.

The consensus of a leading scientific panel in 1930 was that oral hygiene products could not prevent dental caries. Their view was that dental caries prevention required the proper mineralisation of teeth and that vitamin D could achieve this goal. Over a hundred subsequent controlled trials, conducted over seven decades, largely confirmed that this scientific panel had made the right decisions. They had, in 1930, when it comes to dental caries, correctly endorsed vitamin D products as dental caries prophylactics and oral hygiene products as cosmetics. And yet, despite this consistent scientific evidence for close to a century, an opposing conventional wisdom emerged which thrives to this day: oral hygiene habits (without fluoride) protect the teeth from dental caries, and vitamin D plays no role in dental caries prevention. This historical analysis explores whether persistent advertising can deeply engrain memes on dental caries prevention which conflict with controlled trial results. The question is raised whether professional organisations, with a dependence on advertising revenues, can become complicit in amplifying advertised health claims which are inconsistent with the principles of evidence-based medicine.