Pre- and post-irrigation with biosynthesized and chemically synthesized silver nano-particles: a comparative analysis of dentin micro-hardness, surface roughness, and chemical changes

Introduction:
Chemical disinfection is crucial in endodontic therapy to ensure effective cleansing of root canal system. The choice of irrigation solution is pivotal, as it should possess antibacterial properties while being able to remove debris and smear layer components without compromising dentin’s integrity.

Objectives:
The objective of the present study was to compare the effects of biosynthesized silver nano-particles synthesized from Azadirachta indica (neem; A. indica AgNPs) and chemically synthesized silver nano-particles synthesized from trisodium citrate (TCS AgNPs), on hardness, roughness, and chemical properties of dentin, and to compared them with commonly used irrigation solutions (sodium hypochlorite – NaOCl) and distilled water (control).

Material and methods:
This in vitro study evaluated the effects of various irrigation solutions, including A. indica AgNPs, TCS AgNPs, NaOCl, and distilled water, on dentin micro-hardness, surface roughness, and chemical composition. Forty single-rooted human teeth were divided into four groups and treated with re-spective irrigation solutions. Micro-hardness, surface roughness, and Fourier transform infrared spectroscopy (FTIR) were used to assess dentin properties before and after treatment.

Results:
Analysis of variance (ANOVA) revealed no significant difference in dentin micro-hardness and surface rough-ness between the groups (p < 0.05). However, FTIR values showed significant variations in dentin composition among the irrigation solutions. A. indica AgNPs exhibited the least changes in dentin composition compared with TCS AgNPs, NaOCl, and distilled water.

Conclusions:
While all irrigation solutions caused changes in dentin properties, biosynthesized AgNPs showed promising results in maintaining dentin integrity during endodontic irrigation. Further research is needed to explore clinical implications of these findings.