[A new classif ication in Periodontology (Chicago 2017). Impact in Orthodontics].

In 2018, a new « Classification of Periodontal and Peri-implant Diseases and Conditions » was adopted by the American Academy of Periodontology and the European Federation of Periodontology. Numerous studies in recent years have improved the understanding of periodontal diseases and their risk factors, leading to an update of the 1999 classification. Among the major changes is the development of a classification of periodontitis into different stages and grades and the notion of periodontal health, an essential prerequisite for orthodontic treatment. Based on the analysis of the 24 published articles, this work provides explanations regarding the main changes that orthodontists may face. The classification of Chicago precisely defines periodontal health and proposes a new system for characterizing periodontitis in stages and grades. It then becomes a valuable aid for the orthodontist in risk detection and periodontal screening. The knowledge of this new classification is essential for reliable communication between dentists, periodontists and orthodontists, in order to guarantee the success of orthodontic treatment.