The bacteria colonizing the hard and soft tissues of the oral cavity are known to profoundly influence oral health and disease. For many years, scientists have realized that it is impossible to fully understand oral health and disease without identifying and understanding the pathogenic potential of all of the bacteria that colonize the oral cavity. Based on traditional identification of bacteria in cultural studies And more recent identification of bacteria in culture independent molecular studies, over 700 been identified from the periodontal pocket, the remaining 300 species have been identified from other oral sites such as the tongue, oral mucous membranes, carious lesions, and endodontic infections. Any particular individual is thought to have approximately 100-200 of these 700 species of oral bacteria so there is substantial diversity among different people.