Abstract
Periodontal pathogens have always captivated the attention of periodontists and microbiologists as it account for causing periodontal disease in 90% of the population globally. Clinical and experimental studies have confirmed that destructive activity on the periodontium is due to certain strains of bacteria that occupy a relatively small portion of dental biofilm. Among them, the green and the red complex bacteria enjoy the popularity of being the most notorious strain in disease initiation and progression. The genera of green complex bacteria comprise three pathogens- Aggregatibacter actinomyecetecomitans, Capnocytophaga, and Eikenella corrodens. The group possesses several stratagems and key elements that aid them in escaping the immune surveillance and creating a harsh environment for the periodontium. The review focuses on defining the green complex bacteria and their role in periodontitis.