Effectiveness of Piper longum Extract as Natural Irrigant on Antimicrobial Properties and Smear Layer Removal: A...

This study aims to evaluate the antimicrobial effectiveness and smear layer removal of Piper longum extract as a natural irrigant in root canal therapy compared to ethylenediaminetetraacetic acid (EDTA), a commonly used irrigant.

A total of 0.5 gm of powdered P. longum fruit was extracted using distilled water and heat. Eighteen freshly extracted human maxillary central incisors were selected and decoronated to a length of 16 mm. Root canals were prepared and divided into two groups (n = 9 each): Group I was treated with 17% EDTA (control), and group II was treated with P. longum extract (test). Irrigants were activated using gutta-percha cones. Samples were sectioned for SEM evaluation at coronal, middle, and apical regions. SEM imaging was performed at ×200 (debris) and ×1,000 (smear layer). The antimicrobial analysis was done by incubating a fresh suspension of microorganisms, and the sterile wells bored were filled with varying concentrations of P. longum, and inhibition zones were measured using a vernier caliper for positive, negative, and experimental groups. Data were recorded and statistically analyzed using SPSS software.

Mean smear layer scores were 2.11 ± 0.60 EDTA and 1.66 ± 0.70 (P. longum). Mean debris scores were 2.22 ± 0.44 EDTA and 2.11 ± 0.33 (P. longum). Piper longum demonstrated enhanced smear layer removal and comparable debris clearance. Antimicrobial zones of inhibition for P. longum at 150 µL ranged from 12 mm (Streptococcus mutans) to 11 mm (Candida albicans), comparable to the positive control, ampicillin (bacteria) and fluconazole (fungi). The differences in inhibition zones between P. longum and the positive control were statistically significant (p < 0.05). No zones were observed for negative controls (distilled water).

Piper longum extract demonstrated substantial efficacy in removing the smear layer and reducing microbial load within the root canal system, comparable to conventional EDTA.

There is a growing need for biocompatible and sustainable alternatives to synthetic irrigants, which may cause adverse effects such as tissue toxicity or dentin erosion. This study explores the potential of P. longum, a natural herbal extract with known antimicrobial and anti-inflammatory properties, as an adjunctive irrigant in root canal therapy. How to cite this article: Varshasree S, Sinduja P, Manjesh D, et al. Effectiveness of Piper longum Extract as Natural Irrigant on Antimicrobial Properties and Smear Layer Removal: A Scanning Electron Microscope Study. J Contemp Dent Pract 2025;26(11):1073-1078.