Comparative evaluation of apical depth penetration and postoperative pain using 9% 1-Hydroxyethylidene-1, 1-Diphosphonic Acid (HEDP) as continuous chelation and 5% glycolic acid, 10% glycolic acid,17% EDTA as sequential chelation using sonic irrigation technique in symptomatic vital teeth: A double blinded randomized controlled trial.

This study will compare four different irrigation protocols in root canal treatment to assess their effectiveness in irrigant penetration and post-operative pain.

 Patient selection

 Patients who will fulfil inclusion criteria will be randomly divided into four groups:

 Group 1: Sequential chelation with 2.5% NaOCl and 17% EDTA.

Group 2: Sequential chelation with 2.5% NaOCl and 5% Glycolic acid.

Group 3: Sequential chelation with 2.5% NaOCl and 10% Glycolic acid.

Group 4:  Continuous chelation with 9% HEDP + 2.5% NaOCl.

 Root canal procedure:

 Patients will be anesthetized, isolated with a rubber dam, and canals will be accessed and prepared with ProTaper Gold instruments.

All four groups will receive irrigation after each file according to their respective group.

 Irrigant penetration evaluation:

 After final irrigation, 1 ml of radio-opaque dye will be injected into the canal and a radiograph will be taken to evaluate the irrigant penetration.

 Post-operative procedure:

 After drying the canals, the tooth will be temporarily sealed, and patients will return for obturation and post-operative restoration.

 Pain evaluation:

 Post-operative pain is recorded at 6, 24, and 48 hours using the NRS pain scale. If pain persists, patients will be prescribed an escape drug and excluded from the study.

 This study aims to determine which irrigation method provides better irrigant penetration and reduces post-operative pain.