Inclusion Criteria:  • Asymptomatic patients with age range 20 - 40 years  Necrotic, single canal maxillary and mandibular teeth with periapical infection presented as radiolucency or widening in the periodontal membrane space. Medically - free of any systemic disease Teeth with complete root formation  Exclusion Criteria:  • Pregnant or lactating females  Teeth with vital pulps, internal or external resorption or anatomic abnormalities Teeth with cracks, curvatures, root caries and calcified canals Double or triple-rooted teeth Patients with facial swelling, acute pulpal or periapical lesion Teeth that are not indicated for endodontic treatment: Bad oral hygiene, mobile or recessed Previously endodontically-treated teeth