In the proposed continuation project a team of investigators from the State University of New York at Buffalo, Periodontal Disease Clinical Research Center, will continue to collaborate with the diabetes epidemiologists at the National Institutes of Health Southwestern Field Study Section in Phoenix, Arizona. We propose to continue studying the relationships between diabetes and periodontal disease in a well-studied, stable population of Pima Indians who suffer from a high prevalence of non-insulin dependent diabetes mellitus (NIDDM). Studies will be carried out on subjects residing on the Gila River Indian Reservation in southwest Arizona to further evaluate the incidence, prevalence, and severity of periodontal diseases and other oral conditions in diabetic and non-diabetic subjects as well as those with impaired glucose tolerance. We propose to correlate these findings with other complications of diabetes mellitus and to evaluate the microbiological and host response factors operative in diabetics as compared to non-diabetics. The specific aims are directed to determining the contribution of diabetic complications and control, duration of diabetes, age and sex, and the relationship of the HLA locus to periodontal diseases in diabetic Pimas. We propose to carry out longitudinal studies to determine the incidence of periodontal disease in Pima Indians, and to study its relationship to diabetes and diabetic complications. We also propose to determine the relationship of periodontal disease to diabetic family history among the Pima Indians. Studies to determine the role of immunologic factors in Pima Indians with periodontal disease by evaluating the antibody-neutrophil axis will be carried out, as will evaluation of the subgingival microflora. An assessment of the efficacy of periodontal treatment and initial healing in diabetics using tetracycline, a drug with antimicrobial and anti-inflammatory effects is also proposed. A better understanding of the role of diabetes in the initiation and progression of periodontal disease, of the host-bacterial interactions occurring in diabetics, as well as the efficacy of treatment of diabetics is a long range goal of the project. In the treatment study we will also assess the effect of periodontal disease on the diabetic state. The proposal capitalizes on the initial successful studies of the oral health status of the diabetic Pimas and proposes to continue in-depth the study of two important diseases in a community with a high prevalence of both diseases.