Clinical Research Directory

Inclusion Criteria * Patients presenting with a single rooted mandibular premolar tooth with a closed apex and a single patent canal type I in Vertucci's classification (Vertucci et al., 1974). * Having a necrotic pulp. * A pocket depth measurement of \< 3 mm. * Teeth with no previous history of endodontic treatment. * Teeth with periapical lesions of endodontic origin having a periapical index score of 4 or 5 (Orstavik et al., 1986) * Patients who took antibiotics within the period of three months before the study. * Non-restorable teeth. * Teeth with periodontal pockets deeper than 4mm, with or without concomitant or combined endo-perio communication * Multirooted teeth. * Previously initiated or treated teeth. * Teeth with root canal calcifications or resorption. * Teeth with internal/external root resorption or root fracture. * Immune-compromised patients or patients with systemic diseases i.e. (diabetes mellitus, human immunodeficiency virus, leukemia, neutropenia, undergoing chemo- or systemic corticosteroid therapy) * Teeth with root curvature of more than 15 degrees. * Pregnant women * Patients with known sensitivity to the medicaments used in this study.