Dental services utilization varies and access to periodontal therapy is not uniform. The objectives were to study an adult population of Medicaid eligible subjects in the Kitsap County, State of Washington, USA: (1) to assess their oral health status, specifically periodontal conditions, and (2) to assess their use of dental services and behavioral beliefs in relation to dental diseases. 1500 randomly selected eligible households were invited to a cost-free dental examination. The Periodontal Screening and Recording (PSR) index and six bitewing x-ray films were obtained. Subjects responded to a service utilization questionnaire. A telephone interview was performed with 100 randomly selected eligible subjects to assess their behavioral beliefs about dentistry. 132 (8.8%) of the contacted subjects responded while only 4.5% came to the clinical examination. The mean age of the subjects was 35.0 years (S.D. 13.6, range 18 to 78 years) and 73.4% were women. Bleeding on probing was found in 82.8%, and 7.8% of the subjects had teeth with suppurating gingival conditions. Supra, or sub-gingival calculus could be identified in 95.3% of the subjects. Probing depths > 5.5 mm (not accounting for surfaces of third molars) were found in 11.3%, and radiographic evidence of vertical defects >= 3 mm in 47% of the subjects. Tooth decay in need of urgent dental care was found in 75% of the subjects. Cost (63.2%) and lack of dental insurance (51.3%) were primary factors for not seeking care but 48.7% had no desire to enroll in a "no cost" dental therapy program. Dental fear was an obstacle to care in only 2.6% of the subjects. Primary barriers to the utilization of dental services in low income, uninsured populations were: (1) a pre-occupation with other daily issues, financial being the greatest, (2) an attitude of waiting for a problem to occur before seeking dental care, (3) that tooth extraction is the solution or only available treatment option. Keywords: adult, periodontitis, tooth decay, Medicaid, low income, tooth loss, self-perception, self-efficacy, oral radiographs, alveolar bone loss