To the Editor The study by Engebretson and colleagues1 adds knowledge about the effect of periodontal treatment on glycemic control in patients with type 2 diabetes and moderate to advanced chronic periodontitis. The authors of this multicenter randomized study (the Diabetes and Periodontal Therapy Trial [DPTT]) concluded that nonsurgical periodontal therapy did not improve HbA1c values. Despite its high internal validity, this trial raises some important interpretation issues, particularly regarding the interventions that were compared.
Vergnes J. Hemoglobin A1c Levels Among Patients With Diabetes Receiving Nonsurgical Periodontal Treatment. JAMA. 2014;311(18):1920-1921. doi:10.1001/jama.2014.2225