Antimicrobial susceptibilities of bacteria associated with periodontal disease.

A total of 193 bacterial strains were tested for their susceptibilities to 14 antimicrobial agents. Penicillin G was active at 2 U/ml against 98% of the oral isolates. Other antibiotics with good activity were cefoperazone, moxalactam, Sch 29,482, and clindamycin. Metronidazole was active against more than 90% of the anaerobic bacteria and Capnocytophaga but was inactive against most other microaerophilic and facultative strains.