Neem comparable to sodium hypochlorite as root canal irrigant for postoperative pain reduction

Pain intensity was assessed using a numerical rating scale (NRS) 6, 12, 24 and 48 h following instrumentation and canal filling. Endotoxin samples were collected using three paper points before and after canal instrumentation and a sandwich ELISA method was used to quantify the level of endotoxins.

Demographic, baseline, and outcome data were collected and analysed using chi-square tests (for the comparisons of categorical variables), Mann–Whitney tests (for non-normally distributed variables) and Student's t tests (for normally distributed variables), A P-value < 0.05 was considered to be statistically significant.

The results showed that –

1. The mean pain scores within the two groups decreased continually over time.
2. The mean pain scores in the Neem group were lower than those in the 2.5% NaOCl group at 6, 12, 24 and 48 h following instrumentation and canal filling with no significant difference between them except at 24 h following instrumentation (P = 0.012).
3. Both irrigants significantly reduced endotoxin levels compared to the pre-instrumentation samples (P < 0.001) by 8% for the NaOCL group and 18% for the Neem group.

Therefore, the authors concluded that "Neem and 2.5% NaOCl were not significantly different in terms of reducing the intensity of post-operative pain during all follow-up periods except at 24 h following instrumentation where Neem was associated with lower pain intensity. Both irrigants significantly reduced endotoxin levels but were not effective in eliminating endotoxins completely from root canals of mandibular molars with necrotic pulps."