The occurrence of subgingival staphylococci was determined in 506 individuals with advanced adult periodontitis, 108 with early-onset periodontitis, 13 with localized juvenile periodontitis, 18 with gingivitis, and 13 with 20 failing osseointegrated titanium dental implants. Subgingival samples were collected with paper points and transported in VMGA III. The bacterial samples were plated on Staphylococcus 110 medium which was incubated in 10% CO2, and on enriched brucella blood agar, which was incubated anaerobically. Staphylococcal isolates from 94 adult periodontitis subjects were speciated using the API STAPH Trac micromethod kit system and the Bacto Staph latex agglutination test for coagulase activity. Staphylococcus epidermidis comprised 45.8% and Staphylococcus aureus 22.3% of total staphylococcal isolates. At 1 microgram/ml, in vitro resistance by staphylococci was found to tetracycline (14.4% of isolates), penicillin (4.9%), erythromycin (12.1%), and metronidazole (31.9%). Subgingival staphylococci were isolated from approximately 50% of gingivitis and periodontitis patients. No statistically significant differences were found between these patient groups in the prevalence or mean proportions of staphylococci recovered. "Periimplantitis" lesions exhibited significantly higher proportions of staphylococci (15.1%) than gingivitis (0.06%) or periodontitis (1.2%) lesions. Staphylococci may play a role in some failing osseointegrated dental implants.