Periodontitis: Consensus report of workgroup 2 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions

A new periodontitis classification scheme has been adopted, in which forms of thedisease previously recognized as “chronic” or “aggressive” are now g rouped undera single category (“periodontitis”) and are further characterized based on a multi-dimensional staging and grading system. Staging is largely dependent upon the sever-ity of disease at presentation as well as on the complexity of disease management,while grading provides supplemental information about biological features of thedisease including a history-based analysis of the rate of periodontitis progression;assessment of the risk for further progression; analysis of possible poor outcomes oftreatment; and assessment of the risk that the disease or its treatment may negativelyaffect the general health of the patient.Necrotizing periodontal diseases, whose characteristic clinical phenotype includestypical features (papilla necrosis, bleeding, and pain) and are associated with hostimmune response impairments, remain a distinct periodontitis category.Endodontic-periodontal lesions, defined by a pathological communication betweenthe pulpal and periodontal tissues at a given tooth, occur in either an acute or a chronicform, and are classified according to signs and symptoms that have direct impact ontheir prognosis and treatment.Periodont al abscesses are defined as acute lesions characterized by localized accu-mulation of pus within the gingival wall of t he periodontal pocket/sulcus, rapid tissuedestruction and are associated wit h risk for systemic dissemination