Preoperative pain was recorded using a Numerical Rating Scale (NRS) before treatment. All procedures were performed in a single visit by one operator under 3× magnification. Local anesthesia was achieved with 4% articaine containing 1:100,000 epinephrine. After rubber dam isolation, caries and existing restorations were removed and an endodontic access cavity was prepared under copious water cooling using high-speed sterile diamond burs.

The working length was established with an electronic apex locator (Root ZX Mini) and confirmed radiographically. In this group, apical patency was not maintained: after working length determination, all subsequent instrumentation was confined within the working length, and no file was advanced beyond the apical foramen.

Root canals were shaped using the One Curve NiTi rotary system (25/.06 or 35/.04) with a crown-down technique. During shaping, canals were irrigated with a total of 10 mL of 2.5% sodium hypochlorite (2 mL after each shaping step) de

Preoperative pain was recorded using a Numerical Rating Scale (NRS) before treatment. All procedures were performed in a single visit by one operator under 3× magnification. Local anesthesia was achieved with 4% articaine containing 1:100,000 epinephrine. After rubber dam isolation, caries and existing restorations were removed and an endodontic access cavity was prepared under copious water cooling using high-speed sterile diamond burs.

The working length was established with an electronic apex locator (Root ZX Mini) and confirmed radiographically. In this group, apical patency was maintained: a #10 K-file was gently advanced 1 mm beyond the working length at each instrument change to prevent apical blockage, remove accumulated debris, and facilitate irrigant delivery to the apical terminus.

Root canals were shaped using the One Curve NiTi rotary system (25/.06 or 35/.04) with a crown-down technique. During shaping, canals were irrigated with a total of 10 mL of 2.5% sodium hypochl

Single-visit root canal treatment of asymptomatic vital single-rooted teeth in which apical patency is maintained. After working length determination with an electronic apex locator and radiographic confirmation, a #10 K-file is gently extended 1 mm beyond the working length at each instrument change to prevent apical blockage, remove debris, and facilitate irrigant delivery to the apical terminus. All other steps, including anesthesia, rubber dam isolation, access cavity preparation, rotary shaping with the One Curve NiTi system, standardized irrigation with 2.5% NaOCl and 17% EDTA, obturation, and definitive composite restoration, follow a standardized protocol.

The numerical rating scale for pain is an 11-point scale from 0 to 10, where 0 means no pain and 10 means the worst pain imaginable. The patient is asked to choose the number that best represents the intensity of pain he or she feels at that moment. It is used to assess the severity of postoperative pain and to help evaluate the need for and response to analgesic medication. Also called NRS.