Overview
Chronic periodontitis is a multifactorial inflammatory disease of the periodontium — the supporting structures of the tooth — characterised by progressive loss of clinical attachment, alveolar bone destruction, and periodontal pocket formation. It is the most common form of periodontitis and a leading cause of tooth loss in adults worldwide.
The 2017 World Workshop on the Classification of Periodontal Diseases replaced the term 'chronic periodontitis' with a Staging (I–IV) and Grading (A–C) system. Stage reflects severity and complexity; Grade reflects rate of progression and systemic risk factors.
Unlike gingivitis, which is confined to the gingiva and fully reversible, periodontitis involves irreversible loss of alveolar bone and periodontal ligament. Once attachment is lost, it cannot be fully regenerated without surgical intervention.