Diabetes mellitus is emerging as a global epidemic whose complications impact significantly on quality of life, longevity and health care costs. Periodontal Disease is more severe, but not necessarily more prevalent, in patients with diabetes than in those without. Current evidence suggests that periodontal disease adversely affects diabetes outcomes, although evidence for treatment benefits is currently lacking. Patients with diabetes should be told that periodontal disease risk is increased by diabetes. They should also be told that if they suffer from periodontal disease, they may have more difficulty with glycemic control. As part of their initial evaluation, patients with type 1, type 2 and gestational diabetes (GDM) should receive a thorough oral examination that includes a comprehensive periodontal examination. Subsequent periodontal examinations should occur (as directed by dental professionals) as part of their ongoing management of diabetes. Even if no periodontitis is diagnosed initially, annual periodontal review is recommended.