Diabetes and Periodontal Therapy Trial

This study is a multicenter, randomized, controlled, single-masked, Phase III trial to
determine if non-surgical periodontal therapy (scaling and root planing) is efficacious in
reducing elevated glycosylated hemoglobin (HbA1c) at 6 months post-randomization in subjects
with type 2 diabetes and untreated, moderate to advanced chronic periodontitis. Six hundred
adults with a diagnosis of type 2 diabetes and chronic periodontitis will be randomized at
three Clinical Sites; University of Alabama at Birmingham; the University of Minnesota,
Minneapolis; and the University of Texas Health Science Center, San Antonio. The Core
Laboratory will be located at the University of Minnesota and the Study Chair's Office and
Coordinating Center will be located at Stony Brook University, Stony Brook, New York.

Eligible participants will be randomly assigned to receive either initial non-surgical
periodontal therapy with chlorhexidine rinse (treatment subjects) or delayed non-surgical
periodontal therapy (control subjects). Control subjects will be offered delayed
periodontal therapy (scaling and root planing) following the 6 month visit. Participants
meeting all other eligibility criteria and needing essential dental care, i.e., for broken,
grossly carious or abscessed teeth, may enroll only following completion of necessary dental
treatment. Participants in both study arms will receive oral hygiene instruction and
healthy lifestyle information (e.g. diet, exercise) at baseline and at the 3 and 6 month
visits.

Periodontal data will be recorded by trained and calibrated examiners at baseline and 3 and
6 months following randomization. Fasting blood will collected at baseline and at 3 and 6
months to measure intermediate links in the putative causal chain between periodontitis and
glycemic control. The periodontal health of all subjects will be monitored, and any subject
who experiences progressive periodontitis during the study will be provided with
non-surgical rescue therapy.