Clinical aspects of pathogenesis of cloronic apical periodontitis

Endodontic treatment is aimed to eliminate bacteria from infected root canals that will later be sealed to prevent recontamination. The prolonged healing process of many periapical lesions increases the possibility that the activated cells in the lesion may remain activated long after the initial cause of their activation has been eliminated. Macrophages are known to persist in tissues for many months and if their state of activation persists, they may inhibit the fibroblasts, maintain osteoclastic activity, and inhibit osteogenesis, thus preventing both soft connective tissue and bone repair.