The document discusses pulp and periapical diseases. It begins by describing the pathobiology of the periapex and classifying pulpoperipaical pathoses. It then discusses the classifications of Franklin Weine and the WHO for pulpoperipaical lesions. Key lesions discussed include acute and chronic apical periodontitis, periapical granuloma, periapical cyst, condensing osteitis, and Ludwig's angina. Differential diagnoses and clinical signs and symptoms are also covered.