The Multi-Center Randomized Controlled Trial (RCT) Published by the Journal of the American Medical Association (JAMA) on the Effect of Periodontal Therapy on Glycated Hemoglobin (HbA1c) Has Fundamental Problems

Article title and bibliographic informationThe effect of nonsurgical periodontal therapy on hemoglobin A1c levels in persons with type 2 diabetes and chronic periodontitis: a randomized clinical trial.Engebretson SP, Hyman LG, Michalowicz BS, Schoenfeld ER, Gelato MC, Hou W, et al (16 authors). JAMA 2013;310(23):2523-32.ReviewersWenche S. Borgnakke, Iain L. C. Chapple, Robert J. Genco, Gary Armitage, P. Mark Bartold, Francesco D'Aiuto, Paul I. Eke, William V. Giannobile, Thomas Kocher, Kenneth S. Kornman, Niklaus P. Lang, Phoebus N. Madianos, Shinya Murakami, Fusanori Nishimura, Steven Offenbacher, Philip M. Preshaw, Amin ur Rahman, Mariano Sanz, Jørgen Slots, Maurizio S. Tonetti, Thomas E. Van DykePurpose/QuestionDoes non-surgical periodontal treatment reduce levels of HbA1c in persons with type 2 diabetes and moderate to advanced chronic periodontitis?Source of fundingUS Government – National Institute of Dental and Craniofacial Research, National Institutes of Health: Cooperative agreements ($15.4M): 1) UO1 DE018902 (Dr. Engebretson: $11.1M) and 2) U01 DE018886 (Dr. Hyman: $4.3M)Type of study/DesignMulti-center RCT. Trial Registration: clinicaltrials.gov identifier: NCT00997178.Level of evidenceLevel 2: Limited-quality, patient-oriented evidenceStrength of recommendation gradeNot applicable