Periodontal tissues has many causes, including some specific pathogenic bacteria such as Aggregatibacter actynomycestemcomytan, porphymonas gingivalis, parvimonas micra... Identification of some bacteria causing periodontal disease that Generalized aggressive periodontitis in a group of patients aged 20 - 45 years, determined by anaerobic bacterial culture and polymeraase chain reaction (PCR) techniques.