clinically compare the intensity of post-operative pain and the amount of bacterial load reduction after using 20% Epigallocatechin-3-gallate solution during chemomechanical preparation, versus 2.5% NaOCl, in asymptomatic necrotic mandibular premolars treated in a single visit.

The patients will be randomly divided into 2 groups. Intervention group (20% epigallocatechin-3-gallate solution root canal irrigant) and control group (2.5% sodium hypochlorite root canal irrigant).

Post-operative pain will be measured at 6, 12, 24 and 48 hours post-operatively. The pain will be recorded using the Numerical Rating Scale (NRS).

Amount of bacterial load reduction The intracanal bacterial load reduction will be determined using agar culture technique by counting the colony forming units per milliliter (CFUs/mL) before and after root canal preparation.

The inclusion criteria:

1. Systematically healthy patient (ASA I, II).
2. Age between 18 and 45 years
3. Male or female.
4. Asymptomatic mandibular premolar teeth diagnosed with pulp necrosis.

The exclusion criteria:

1. Medically compromised patients having significant systemic disorders. (ASA III or IV).

2. Teeth with:

   • Immature roots
   • Association with swelling or sinus tract.
   • Acute peri-apical abscess or acute exacerbation of a chronic abscess.
   • Mobility Grade II or III
   • Previously accessed or endodontically treated
   • Deep periodontal pockets more than 4 mm
   • Vertical root fractures, coronal perforation, calcification, and external or internal root resorptions.

3. Patients who could not interpret the NRS.