The microflora of odontogenic infections is typically polymicrobial with increased resistance rates against various antibiotics. The purpose of the present study was to analyze bacterial spectra and resistance in odontogenic infections under routineous conditions.Microbiological samples were collected and transported under routineous conditions in a prospective study of 19 patients. All Bacterial spectra and resistance rates were compared with the results of a former prospective evaluation.There were 11 men, 5 woman and 3 children (age range of 2-86 years). A total of only 38 bacterial strains were analyzed. The ratio between aerobes and anaerobes was nearly 1:1. The resistance rates were nearly the same for Penicillin G, but a 2-fold increased resistance for clindamycin against aerobes and a more than 10-fold increased resistance against anaerobes was noted.Prospective studies under standardized conditions are necessary to isolate strict anaerobes and to detect changes in antibiotic efficiency.