Clinical Research Directory

Inclusion Criteria: 1. Patients presenting with a single rooted tooth (maxillary anteriors and mandibular premolars) with closed apex and a single patent canal type I in Vertucci's classification (Vertucci et al., 1974) 2. Having a necrotic pulp and asymptomatic apical periodontitis (periapical lesion). 3. Periapical lesions of endodontic origin with a diameter ranging from 2 to 5mm, having a periapical index score of 4 or 5 (Orstavik, Kerekes and Eriksen, 1986) Exclusion Criteria: (i) Patients with pain before treatment (ii) Patients having chronic condition requiring the intake of anti-inflammatory/antibiotic drugs. (iii) Teeth having non-restorable tooth with gross carious lesions, fractures, internal or external root resorption or cracks involving the periodontium. (iv) Root canals in which patency for periapical fluid sampling could not be achieved. (v) immune-compromised patients or patients with complicated systemic diseases, physical disability or psychological problems (vi) patients received antibiotic therapy within the last 3months. (vii) Teeth associated with bone expansion or with a history of endodontic treatment. (viii) Teeth with periodontal pockets deeper than 4mm, with or without concomitant or combined endo-perio communication.