Antimicrobial Activity of Gels Supplemented With Nanoparticles as Intracanal Medication in Endodontics: A Systematic Review and Meta-Analysis of In Vitro, In Vivo, and RCT Studies

Abstract

Background: The compalete eradication of microorganisms within the root canal system remains a challenge in endodontic treatment. Gels supplemented with nanoparticles, particularly silver nanoparticles (AgNPs), have shown promise in enhancing antimicrobial efficacy. This systematic review and meta-analysis aimed to evaluate the antimicrobial activity of these nanoparticle-supplemented gels as intracanal medication in endodontics. Methods: A comprehensive search was conducted in PubMed, Web of Science, and SCOPUS databases up to September 2024 using specific keywords related to nanoparticles, gels, and antimicrobial activity in endodontics. Only studies published in English were included. In vitro, in vivo, and randomized clinical trials (RCTs) comparing nanoparticle gels with conventional antimicrobial agents were selected based on predefined inclusion and exclusion criteria. Data extraction and risk of bias assessment were performed by independent reviewers. A random-effects model was employed for the meta-analysis to estimate the overall antimicrobial effectiveness of the nanoparticle-supplemented gels. Heterogeneity among studies was evaluated using the I2 statistic. Results: Out of 991 identified records, 752 were screened after duplicate removal, and 24 articles underwent full-text review. Six studies met the eligibility criteria and were included in the final analysis, comprising three in vitro studies, one in vivo study, and RCTs. The meta-analysis revealed that gels supplemented with nanoparticles exhibited a statistically significant positive antimicrobial effect in in vitro studies (pooled effect size: 5.96; 95% CI: [0.92, 10.99]). However, high heterogeneity (I2 = 96%) was observed. In contrast, the meta-analysis of RCTs indicated no significant overall antimicrobial effect (combined effect: 1.04; 95% CI: [−0.06, 2.15]; I2 = 76%). Funnel plot asymmetry suggested potential publication bias. Conclusions: Gels supplemented with nanoparticles show potential antimicrobial efficacy in vitro, but the evidence from clinical trials is inconsistent. High heterogeneity and potential publication bias indicate the need for more standardized clinical research to accurately assess the effectiveness of nanoparticle-supplemented gels in endodontic treatment.