Birth of a conspiracy theory? In defense of oral hygiene.

“Historical perspectives on advertising and the meme that personal oral hygiene prevents dental caries”   by Hujoel V.P.,  Gerontology, 2018

This alarming article states that insufficient amounts of vitamin D rather than dental plaques caused by mouth bacteria cause tooth decay thus contradicting the consensus (Bowen, 2016; Selvitz et al., 2007; Tvetman S. et al., 2003; ). The author also calls dental hygiene, in particular, using fluoride products “a meme” introduced by the pharmaceutical industry and adopted by the dental profession because of professional dental association financing by toothpaste manufacturers.

To confirm this, the author uses blatant misinformation. He writes in the abstract that “over a hundred subsequent controlled trials, conducted over seven decades, largely confirmed  [that dental caries prevention required the proper mineralisation of teeth and that vitamin D could achieve this goal.]”.

To back this up, in the introduction he cites two metanalyses published in 1952 and 2013. The latter _by the same author_ states that “Twenty‐two of the 24 CCTs predated modern clinical trial design… The relative‐rate estimates of the 24 CCTs exhibited significant heterogeneity (P < 0.0001), and there was evidence of significant publication bias (P < 0.001)…”.

On closer inspection “over seven decades” mean the earliest trial (if we can call it this) was in 1918 followed by a cluster of them in the 1930s and 40s, a gap of  40 years, two trials in 1975 and one in 1989. The gap that significantly changes the hypothesis perception from “for seventy years people were finding strong evidence but ignored it” to  “revisiting badly collected data 40 years later shows some significance”, 1989 – 1930 = 59.

In other words, the literature shows a possible significance of Vitamin D that does not contradict the widely accepted theory of plaque formation and necessity of oral hygiene to prevent it.

Extraordinary claims require very strong supporting evidence. The claim that dental hygiene prevention of dental caries is a ‘meme’ rather than an established paradigm is certainly an extraordinary claim. The author not only fails to provide strong evidence but distorts the evidence he has. Moreover, the article has hallmarks of a conspiracy theory, namely “bad pharma”.

I wonder if the article would’ve been accepted in a journal with a similar impact factor  if the author wasn’t on the  “Gerodontology” editorial board.

I don’t dispute that caries is a complicated process dependent on the multitude of factors, including genetic, microbiome and nutritional components that determine teeth resilience to caries-causing bacteria. I also don’t doubt that the pharmaceutical industry has been making exaggerated claims about dental hygiene efficiency. But all this does not support the idea of modern oral hygiene futility.



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.