Inclusion Criteria:  Systemically healthy patient (ASA I or II).  Mandibular first molar teeth with:  Preoperative sharp pain and symptomatic apical periodontitis Absence or slight widening in the periodontal ligament (PDL). Vital response of pulp tissue to cold pulp tester (ethyl chloride spray) . Positive response to percussion test  Exclusion Criteria:  Medically compromised patients. Pregnant women. Patients reporting bruxism or clenching. Patients allergic to ciprofloxacin or metronidazole. Teeth associated with acute periapical abscess and/or swelling. Greater than grade I mobility or pocket depth greater than 5mm. Size of periapical radiolucency is greater than 8 mm. No restorability: Hopeless tooth. Immature teeth. Radiographic evidence of external or internal root resorption vertical root fracture, perforation, calcification.