The first withdrawn manuscript by Drs. Wenche Borgnakke and Iain Chapple and each and every editor of our hardcore periodontal journals as well as otherwise eminent individual in Periodontology, which had proclaimed that “[t]he randomized controlled trial (RCT) published by the Journal of the American Medical Association (JAMA) on the impact of periodontal therapy on glycated hemoglobin (HbA1c) has fundamental flaws” about the paper by Engebretson et al. (2013), see [pdf], went online today in the Journal of Evidence-Based Dental Practice.
I had wondered before why it had been withdrawn but couldn’t figure that out. Interesting may be that the withdrawn paper had listed all 19 authors, while the current version does not. Maybe that Borgnakke and Chapple are only pawns in a worldwide political enterprise launched by our “thought leaders”. It may also be that more “evidence” (see below), possibly (but rather not) suitable for putting findings by Engebretson et al. (2013) into perspectve, needed to be included in what is almost a revile.
In a recent post, I have very briefly tried to add the findings by Engebretson et al. (December 2013) on effects of non-surgical periodontal therapy on HbA1c levels in diabetics with periodontitis to a meta-analysis of Engebretson and Kocher (April 2013) who had identified 9 small-scale single-center studies. In that meta-analysis, a mean reduction of HbA1c of 0.36% was calculated. Low enough but significant. If the results of the large multicenter study by Engebretson et al. (2013) were added, a random effects model revealed still a tiny but significant reduction of HbA1c of -0.28%, 95% confidence interval: -0.45; -0.10.
I have written about AAP’s centennial and the series of papers celebrating the “literature that shaped modern Periodontology” in several posts, see here and here. In this month’s contribution (in the Academy’s Journal of Periodontology), Steven Offenbacher and James Beck attracted my attention when writing about “Changing Paradigms in the Oral Disease–Systemic Disease Relationship.” Twenty-five years after the first report by Finnish researchers on a certain risk of poor oral health for cardiovascular disease, the incredibe surge of studies all over the world (“Floss or Die!”) may have ceased, paving the way for another overdue paradigm shift.
The paper disappoints. Instead of putting the initial and long-lasting exciting in at least some relation in view of results of recent very large intervention studies which were by and large not able to confirm a postulated benefica effect of treatment of periodontal disease on cardiovascular disease, low birth weight or diabetes, Offenbacher and Beck opened the bottom drwaer and pulled a couple of now questionable studies which, well, misled the public and thousands of researcher worldwide alike. For instance, Frank De Stefano’s paper of 1993 who, based on NHANES I follow-up data, reported a 25% increase of risk in patients with periodontitis. The data had been re-analyzed by Phillipe Hujoel in 2000 including much more careful adjustment of cofounders. They could not find an association. I have reported about the apalling letter to the editors of JAMA by Robert Genco and colleagues here.
And then, of course, the paper by Beck et al. (1996) from the VA Longitudinal Study.
“Our paper showed that periodontal disease was a significant independent risk factor for CVD events after adjusting for traditional risk factors and displayed a dose-dependent increase in risk with increasing periodontal disease severity. Importantly, this paper described a two-component mechanistic working model that linked periodontal disease to cardiovascular disease via systemic bacterial dissemination interacting with the vasculature and activation of the hepatic acute phase response as an inflammatory trigger for CVD. We also hypothesized that there may be an underlying hyperinflammatory trait that served to increase risk for both conditions, suggesting that bacterial exposure in those susceptible individuals would result in even more risk for CVD. In addition, by placing importance on inflammation, it explained how oral infection could influence multiple conditions such as diabetes. Over the next 10 years, many studies supported this basic model. The model is now more than 15 years old, and we would modify it only by adding specific details, such as the hyperinflammatory trait likely being attributable to genetic differences in the innate immune response.” (Emphasis added.)
It has long been clear that the decades-long hype about what is called the Perio-Systemic connection is mainly PR. Recently, a comment writer in the AAP open forum used “self-esteem” as justifaction for exaggerating the issue. I have to admit that I was appalled. After all, we are part of the medical profession. Not exaggerating but putting into perspective the ever emerging “strong” evidence for minor and, most probably, clinically irrelevant effects of periodontal diseases on systemic health is an obligation of a serious member of our profession.
A colleague had sent me yesterday an ad by a company which markets zirconia oxide dental implants (see a more readable pdf here). The company’s circular reasoning seems to be that the risks for some life threatening diseases such as stroke, myocardial infarction, pneumonia etc. may be reduced by extracting periodontitis-affected teeth and replacing them with zirconia implants. While the patient who is not mentioned here is taken for a fool, there seems to be implicit complicity with the dentist who is suggested to use this kind of reasoning in his or her sales conversations.
While all of us eagerly await the promised monthly comments on eleven themes which have been identified by J Perio’s Editor-in-Chief Dr. Kenneth S. Kornman and colleagues Drs. Paul B. Robertson and Ray C. Williams, your humble blogger will just go ahead sharing with my readers own thoughts which came to my mind when reading the extensive reading list on the Literature That Shaped Modern Periodontology. As the responsible teacher of Perio at The Arctic University of Norway, I feel obliged to put the list somewhat into perspective, in particular since Kornman et al. focus on just highly cited papers (which may frequently represent mainstream) and further consensus papers of importance as suggested by various U.S. postgraduate program directors. And especially as a highly esteemed colleague representing another subject here has put the list on fronter as if it was the best since the invention of chocolate ice cream. Since, for undergraduates, the list inevitably will causes if anything but shock and awe, there is apparent need for some moderation.
4. Periodontitis and Other Systemic Diseases Interact – in Both Directions
First, I want to make sure that I am no heretic. Interaction between periodontal disease and systemic health is, of course, an old story which has only been revived about 25 years ago, undoubtedly to some success for larger parts of our profession. For instance, even before 1990 or so it was well known that diabetes mellitus is associated with considerable periodontal morbidity. On the other hand, when having a look at clinical studies back in the 1970s and 1980s, one frequently reads that periodontitis patients “otherwise healthy” had been enrolled in the trials. After having realized in the meantime that periodontitis is associated with whatever chronic disease or condition is considered, be it lung cancer at one extreme or erectile dysfunction at the other, one can only come to the conclusion that the topic, which gets so much attention nowadays, had in the old days completely been ignored (as had been the effect of smoking on periodontal health). That “bad dentistry” may have, in certain cases, even fatal consequences is, on the other hand, not a new idea but had led, in particular in the United States and later, for instance, in Germany to what was sometimes vilified “Gnathology”, which should not be mistaken just as “occlusal ideology” but rather striving for proper biological function of fixed and removable restorations.