Postoperative pain is a frequent complication associated with root canal treatment. The apical extrusion of irrigant and debris, including bacteria and necrotic tissue, may lead to postoperative pain, periapical inflammation, and flare-ups. The instrumentation technique and the file design may affect the amount of debris extrusion.

The aim of this study was to evaluate the influence of instrumentation techniques on the incidence and intensity of postoperative pain after single-visit root canal treatment.

Sixty patients having root canal treatment indication and a single root canal were included in the study. The patients were randomly assigned into 2 groups according to root canal instrumentation technique used. In group 1; ProTaper Next (Dentsply Maillefer, Ballaigues, Switzerland) instruments with rotational motion, in group 2 TF Adaptive (SybronEndo, Orange, CA) instruments with adaptive motion were used for root canal treatments. Root canal treatment was carried out in a single visit and the severity of postoperative pain was assessed via a four-point pain intensity scale. All the participants were called through the phone at 12, 24 and 48h to obtain the pain scores. Data were analyzed using the Mann Whitney-U, Friedman and Wilcoxon tests.

Inclusion Criteria:

• having root canal treatment indication
• single root canal

Exclusion Criteria:

• previously treated tooth

patients referred to dental clinic for endodontic treatment