Abstract
Periodontal disease is an inflammatory condition, clinically characterized by loss of periodontal attachment and bone loss around the tooth. This inflammatory process is initiated as a result of the pathogenic microbial insult which leads to an intense immunoinflammatory infiltrate in the periodontal tissue. This might lead to tooth loss if not appropriately managed. In gingivitis, a reversible form of periodontal disease that does not result in bone loss. Roy Page and Hubert Schroeder reported the first systematic model describing the host response in four types of histopathologic lesions: "initial," "early, "established" and "advanced". Although understanding of the periodontal pathogeneses in the development of gingivitis and periodontitis is largely based on the microbial involvement, further studies highlighted the complexity of the interactions between the periodontopathogens, host response, and modifying factors that contribute to the ultimate outcome of disease development and progression. The aim of this paper is to review the current aspects in the cellular and molecular pathogenesis of periodontal diseases.