The impact of nanoparticles on the physicochemical properties of epoxy resin-based endodontic sealers: A systematic review with a network and pairwise meta-analysis.

Background Epoxy resin-based sealers (ERBSs) are well-established in endodontics. This review evaluated whether the incorporation of nanoparticles (NP) alters their standardized physicochemical properties and further examined potential dose-response effects and the existence of a minimum effective NP weight percentage. Method PubMed, Scopus, Embase, and Web of Science were searched to January 2025. In vitro studies comparing NP-modified and unmodified ERBSs were included if they evaluated ISO/ANSI-ADA-defined properties. Risk of bias was assessed using the QUIN tool. Pairwise and Bayesian/frequentist network meta-analyses were performed. Results Eleven in vitro studies were included. Pairwise meta-analysis showed lower flow for NP-modified ERBSs at 2 wt% compared to controls (MD= -2.29, 95 %CI - 2.91 -1.68). No significant differences were found for solubility (MD 0.01; 95% CI: -0.09 - 0.12), radiopacity (MD 0.06; 95%CI -0.08 - 0.2), or setting time (MD 18.0833 95 %CI -3.09 - 39.25). Network meta-analysis indicated low NP loadings (0.10-0.15 wt%) most improved flow and solubility, while higher loadings (≥5 wt%) reduced flow. A partial dose-response trend was detected for flow and solubility. Discussion A dose-dependent relationship was observed, with lower percentages improving performance, while higher percentages presented adverse effects. Limitations were identified in the included studies such as the lack of particle characterization, inadequate dispersion techniques, and absence of sample size calculation. Subgroup analyses were not feasible due to limited data. Conclusion NPs can be incorporated into ERBSs without compromising their core physicochemical properties. Low weight percentage may enhance performance, but further standardized research is needed to confirm their effect on antibacterial and biological properties and ensure clinical relevance. .