Objectives: This study estimates factors associated with the prevalence of HIV-associated periodontal diseases (HIV-P) and the severity and extent of periodontitis in HIV-infected adults from North Carolina (NC). Methods: Data are derived from a cross-sectional study of HIV-infected adults (total n=326, dentate n=316) treated at the University of North Carolina Hospitals. Outcomes were a diagnosis of HIV-P and measures of probing pocket depth (PPD), recession (REC), and clinical attachment level (CAL). Immunosuppression was measured by peripheral blood CD4+ cells/mm(3). Results: In addition to persons with HIV (non-AIDS), this study included 10 percent of the AIDS cases in North Carolina. Median age was 37 years (range=19-67); 78 percent were male and 60 percent were black. Sixty-two percent of persons had a probing pocket depth greater than or equal to 5 mm; 46%, had recession greater than or equal to 3 mm, and 66 percent had attachment level greater than or equal to 5 mm in one or more sites. Cases of HIV-P (n=15) were rare. Persons taking HIV-antiretroviral medication were one-fifth (OR=0.20; 95% CI=0.07, 0.63) as likely to have HIV-P as those not taking those medications, controlling for CD4+ cell counts. Conclusions: HIV-infected persons in this study group from North Carolina exhibited severe and extensive measures of adult periodontitis. A small proportion experienced a severe form of HIV-P, which was attenuated by antiretroviral therapy.