Periapical lesions are the commonly occurring pathologic lesions that affect the periradicular tissues of the tooth.This lesion can be classified as granuloma, cystic, or abscess .The pathological changes seen in some periradicular and periapical cases are due to the presence of microorganisms, and their byproducts.These released toxins have the ability to diffuse through inflamed pulpal tissue and get into the periapical area. In a necrotic pulp, the lack of blood flow in the root prevents host immunity from eliminating the infection.