It is well known that the normal oral flora consists of hundreds of different bacterial species. Many clinical studies have shown that, of around 400 bacteria found in the mouth and periodontal pockets, only a few have the greatest pathogenic potential for developing severe, progressive periodontal disease.

In recent years, increasing importance has been placed on molecular diagnostics in the treatment of periodontitis to identify individual periodontal pathogens whose excessive proliferation is largely responsible for the destruction of tooth-supporting structures and, later, implants.