Assessment of Postoperative Pain After Using Reciproc Versus One Shape NiTi Systems in Patients With Symptomatic Irreversible Pulpitis: A Randomized Clinical Trial (Part I)

• Full medical and dental history using a schematic dental chart will be obtained from all eligible participants. Each tooth will be evaluated for vitality (sensitivity) of pulp tissues.

The patients will be randomly divided into 2 groups:

• Experimental group: Reciproc reciprocating instrumentation system.
• Control group: One Shape rotary instrumentation system.

• Sequence of Procedural steps

1. Preoperative pain will be assessed by Numerical Rating Scale (NRS) before administration of anesthesia.
2. Local anesthesia will be achieved using 2% lidocaine (1:100,000 adrenaline).
3. An access cavity will be performed using round bur and Endo-Z bur.
4. The tooth will be properly isolated with rubber dam.
5. Working length will be determined using an electronic apex locator, and working length will be confirmed by radiograph using K-file. Then the working length will be established at 0.5 mm up to the radiographic apex.
6. Canals will be explored with hand K-file ISO sizes 10, 15, 20.
7. Mechanical preparation for both groups will be as follows:

• Experimental group:

• Canals will be instrumented using Reciproc reciprocating system set on an electric motor, with adjusted torque and speed according to the manufacturer's instructions.

• There is no need for coronal preflaring with a Gates Glidden drill or an orifice opener since the design of the Reciproc instrument allows any obstructions in the coronal third to be removed, as claimed by the manufacturer.

• Reciproc file selection: R40 (40/0.06) is to be used.

• Control group: