Knowledge catalog
ClassificationK04.5dentistry

Chronic Apical Periodontitis — Classification

Silent periradicular destruction — granuloma and cyst formation at the root apex

Classification

Periapical Granuloma

Granulation tissue mass without epithelial lining; most common (75–85%)

  • Diffuse poorly-defined radiolucency
  • Asymptomatic
  • Responds to non-surgical root canal treatment
  • Histology: macrophages, lymphocytes, plasma cells, fibroblasts

Radicular Cyst

Epithelium-lined cystic cavity; formed by Malassez epithelial rests proliferation

  • Well-defined corticated radiolucency
  • Often larger than granulomas
  • Pocket cyst responds to RCT; true cyst may require surgery
  • Histology: stratified squamous epithelium + inflammatory cell infiltrate in lining

Asymptomatic Apical Periodontitis

Clinical diagnosis correlating to granuloma/cyst histologically

  • No symptoms
  • Radiographic periapical lesion
  • Negative/absent vitality test
  • Incidental finding on routine radiograph