[Diabetes and oral disease].

Periodontal disease is one of the complications in diabetes. We mention about relationship between diabetes and periodontitis from the view of epidemiology, mechanism and effect of intervention treatment. Excellent glycemic control is essential to improve periodontal disease in diabetic patients, and periodontal treatment not only prevents development and progression of diabetes but also prevents its complications. We need to focus on the treatment for both diabetes and periodontal disease, as the disease to affect each other.