The large multi-center intervention trial by Engebretson et al. (2013), who had reported lack of any effect of non-surgical periodontal therapy on HbA1c levels in type 2 diabetes mellitus patients after 3 and 6 months, has been harshly criticized because of very moderate clinical improvements as regards pocket depth reduction (from mean 3.26 mm at baseline) of 0.4 mm (95% CI 0.4; 0.5 mm) and reduction of bleeding on probing (from mean 62%) of 19% (95% CI 15.7; 22.4). What was even more concerning was that, 6 months after seemingly intense treatment (at least 160 minutes of scaling and root planing followed by oral hygiene instruction and, for two weeks, twice daily mouthwash with 0.12% clorhexidine digluconate; then, at both 3- and 6-month follow-up examinations, further oral hygiene instructions and scaling/root planing for another hour), bleeding on probing was still seen at an average of 40% sites while, on average, 70% tooth surfaces were still covered by plaque (from 86% at baseline).
These are undeniable problems of the study. Claims that periodontal treatment was insufficient and, as a consequence, periodontal infection still present in most patients after periodontal therapy, may in fact be justified. It is the sheer size of the attack which is so appalling. Each and every editor of our professional journals and numerous further pundits, altogether 21, had joined, well, the public execution of the study’s principle investigator. Because of unwelcome results of a study with the potential of ending a story, or illusion, once and forever. And, absolutely inappropriate attempts of intimidation of scientists when writing,
“Given the inconlusive nature of these data, we recommend that the existing body of evidence in which meta-analyses consistently conclude that successful periodontal therapy appears to improve glycemic control, should instruct us until results from future studies are reported. We urge all interested parties to refrain from using this study results as a basis for future scientific texts, new research projects, guidelines, policies, and advice regarding the incorporation of necessary periodontal treatment in diabetes management.” (Emphasis added.)
So, censorship. This is absolutely unscientific. Meta-analyses are always preliminary and must incorporate new results on a continuous basis.
After my recent comment on the concerted action of 19 eminent and self-proclaimed eminent periodontal scientists spearheaded by Drs. Borgnakke and Chapple (2014) aiming at smashing findings of a large multicenter randomized controlled trial by Engebretson et al. 2013 on HbA1c levels in type 2 diabetics with moderate or severe periodontitis, I had honestly decided not to report any more on the issue unless an updated systematic review by the Cochrane Collaboration was published. A reader of my blog had contacted CC’s Dr. Terry Simpson who promised that, due to “logistical problem[s] including difficulties with authors not supplying vital information [sic!],” they would likely be able to publish it around the turn of the year.
Now, the final paper was published yesterday in the Journal of Evidence-Based Dental Practice with a few editorial amendments. Borgnakke’s, well, rant is remarkable since it assembles (as reviewers who are also listed as authors) in essence all editors and many members of the editorial boards of our core journals in periodontology and implant dentistry as well as the editor of Journal of Dental Research. I had reported on the history of the paper here and had noted that, after a first version had been withdrawn by the authors earlier this year, Panos N. Papapanou was no longer listed as reviewer in the version which went online on 13 August 2014. Instead, Fusanori Nishimora (an editorial board member of Journal of Periodontal Research who is involved in the so-called Hiroshima Study, see below) had joined the group. While the online early version of Borgnakke’s paper had got the title “The 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,” a slightly moderated version is now provided: “The Multi-Center Randomized Controlled Trial (RCT) Published by the Journal of the American Medical Association (JAMA) on the Effect (sic!) of Periodontal Therapy on Glycated Hemoglobin (HbA1c) Has Fundamental Problems (sic!).”
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.