Patient selection was based on the following criteria: 1) The aims and requirements of the study were freely accepted; 2) Treatment was limited to patients in good health; 3) Patients with symptomatic or asymptomatic teeth with vital pulps and apical periodontitis; 4) A positive response to hot and cold pulp sensitivity tests; 5) Presence of sufficient coronal tooth structure for rubber dam isolation; 6) No prior endodontic treatment on the involved tooth and 7) No analgesics or antibiotics were used five days before the clinical procedures began.