Aim: The present study assessed the effect of Rosmarinus officinalis extract solution versus 2.5%NaOCl as root canal irrigant on the postoperative pain intensity and the bacterial reduction after root canal treatment of necrotic mandibular premolars.
Methodology: Thirty patients with asymptomatic necrotic single-canalled mandibular premolar were included. Diagnosis had been confirmed clinically and radiographically then patients had been allocated randomly in two equal groups. Teeth in the intervention group were irrigated using 25mg/ml Rosmarinus Officinalis extract solution and those in the control group were irrigated by 2.5%NaOCl. Root canal treatment was done in a single visit by M-Pro files during chemo-mechanical preparation and modified single cone technique using resin sealer for obturation. Assessment of Postoperative pain level was done at 6, 12, 24, and 48 hours using Numerical Rating Scale (NRS). Culturing was used for the assessment of intracanal bacterial levels before and following chemo-mechanical preparation. Statical analysis was done for demographic, baseline and all the outcome data.
Results: Rosmarinus officinalis extract solution caused less postoperative pain to 2.5% NaOCl at 6 hours with a significant difference (p=0.007), at 12 hours with a significant difference (p=0.11), and at 24 hours with significant difference (p = 0.029). Both irrigants significantly reduced the amount of intracanal bacterial load.
Conclusion: Rosmarinus Officinalis extract solution could be more effective than 2.5% NaOCl in terms of reducing intensity of postoperative pain. Both irrigations significantly reduced intracanal bacterial levels of necrotic mandibular premolars.
Keywords: Rosmarinus officinalis, Bacterial reduction, postoperative pain, Irrigation, anerobic bacteria, Numerical rating scale (NRS).