Pulp fiction: Japanese university revokes two dentistry PhDs in case involving two dozen retractions

The misconduct case of an endodontics researcher in Japan who already has lost at least 24 papers for data problems has claimed two more casualties: the PhD theses of a pair of scientists he once helped train.

As we reported last year,  Nobuaki Ozeki, who retired from Aichi Gakuin University in 2018, was found to have misused images, fabricated data and recycled text in 22 papers, 21 of which by our count have now been retracted. Ozeki’s total retraction count is 24, as three papers not identified in the investigation have also been retracted.

Now, we’ve learned that the university has revoked the doctoral degrees of two of Ozeki’s co-authors, Hideyuki Yamaguchi and Rie (Satoe) Kawai. Both researchers received their degrees in March 2016. 

Yamaguchi and Kawai are co-authors with Ozeki of the 2013 article “Proinflammatory Cytokines Induce Stromelysin-1–mediated Cell Proliferation in Dental Pulp Fibroblast-like Cells,” which appeared in the Journal of Endodontics. The journal retracted the paper on June 1, with the following statement: 

This article has been retracted at the request of a member of the author team as it contains fabricated/falsified data. All of the authors except Nobuaki Ozeki and Taiki Hiyama have agreed to retract the article; N Ozeki left Aichi Gakuin University in March 2018 and does not respond to coauthor inquiries. T Hiyama left Aichi Gakuin University and could not be reached.

A second new retraction for Ozeki involves a 2015 article in the Journal of the Japanese Society of Dental Conservation titled “New findings of MMP-3 in an in vitro pulpitis model using high-purity odontoblasts derived from stem cells.” According to the notice:

The editorial board has accepted the authors’ request for the withdrawal of this publication that included incorrect data. 

Yamaguchi and Kawai are not co-authors of that article. However, their names appear together on at least nine retracted articles, including the one in the Journal of Endodontics.

Hat tip: Lemonstoism, author of World Fluctuation Watch

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