Comparison of Post-Operative Endodontic Pain Using Sodium Hypochlorite, Hydrogen Peroxide, and Normal Saline as Root Canal Irrigants

Root canal treatment (RCT) is performed to relieve dental pain and eliminate infection within the tooth. The procedure involves mechanical cleaning and shaping of the root canal system, chemical irrigation to remove bacteria and tissue remnants, and sealing of the canals along with restoration of the coronal portion. Treatment is often done over multiple visits, with temporary fillings and medicaments placed between appointments.

Post-treatment pain is common in the inter-appointment period and may be caused by factors such as leakage of irrigants beyond the apex, improper instrumentation, remaining bacteria, endodontic flare-ups, or host-related factors. Chemical irrigation is used alongside mechanical cleaning to reduce microbial load and prevent post-treatment pain.

Irrigants studied:

Sodium hypochlorite (NaOCl): Strong antimicrobial properties, effective in dissolving pulp tissue, but can cause tissue irritation, swelling, and pain if extruded beyond the root apex.

Hydrogen peroxide (H2O2): Helps remove debris physically and has some antimicrobial activity, though its efficacy against bacteria is less well established. Can cause tissue irritation if misused.

Normal saline: Biologically safe but lacks antimicrobial activity. This study is designed as a randomized controlled trial to compare the incidence and intensity of post-endodontic pain in patients receiving these three irrigants in a local clinical setting.

Objective:

To compare post-endodontic pain among patients receiving sodium hypochlorite, hydrogen peroxide, and normal saline as root canal irrigants.

Operational Definitions:

Pain: Assessed using the Visual Analog Scale (VAS). VAS = 0 indicates no pain; VAS ≥ 1 indicates presence of pain.

Acute pulpitis: Diagnosed in patients with VAS pain score ≥ 4, tooth sensitivity on percussion, and radiographic evidence of lamina dura discontinuation or apical radiolucency.

Study Procedures:

Patients will be screened for eligibility. Eligible patients will be randomly assigned to one of three groups: NaOCl, H2O2, or normal saline.

Standard root canal treatment will be performed by trained clinicians. Pain assessment will be recorded at predetermined time points using VAS. Data will be collected, analyzed, and compared between groups to determine which irrigant results in the least post-treatment pain.

• Sodium Hypochlorite 2.5% (Drug): Sodium hypochlorite 2.5% will be used as the root canal irrigant during standard root canal treatment. The solution will be applied throughout the mechanical cleaning and shaping of the canals. Pain will be assessed post-procedure using the Visual Analog Scale (VAS).
• Hydrogen Peroxide (Drug): Hydrogen peroxide 3% will be used as the root canal irrigant during standard root canal treatment. The solution will be applied throughout the mechanical cleaning and shaping of the canals. Pain will be assessed post-procedure using the Visual Analog Scale (VAS).
• Normal Saline (0.9% NaCl) (Drug): Normal saline (0.9% sodium chloride solution) will be used as the root canal irrigant during standard root canal treatment. The solution will be applied throughout the mechanical cleaning and shaping of the canals. Pain will be assessed post-procedure using the Visual Analog Scale (VAS).

Primary outcomes

• Post-operative pain [72 hours after root canal treatment]: Post-operative pain will be measured using a 10-cm Visual Analog Scale (VAS), where 0 indicates no pain and 10 indicates worst possible pain. Pain scores will be recorded at follow-up and compared across the three irrigant groups to determine differences in post-endodontic pain intensity.

Sex: All, ages: 18 Years to 50 Years, accepts healthy volunteers

Inclusion Criteria:

Male or female patients aged 18-50 years. Diagnosed with acute pulpitis with pain duration ≤ 3 days. Planned to undergo root canal treatment. Willing to provide informed consent and comply with follow-up.

Exclusion Criteria:

Teeth presenting with fluctuant facial swelling (acute apical abscess). Teeth with difficult access opening or instrumentation (e.g., malposed teeth). Presence of vertical tooth fracture (root canal treatment contraindicated). Patients with systemic conditions contraindicating dental treatment. Patients currently taking analgesics or antibiotics that may affect pain assessment.