Background: Conventional root canal irrigants such as sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) are widely used because of their antimicrobial and chelating properties; however, their effectiveness may be limited by biofilm resistance and complex root canal anatomy, and they may adversely affect dentin microstructure and regenerative potential. Objective: This systematic review evaluated preclinical evidence on nanoparticle-based endodontic irrigation with respect to antimicrobial and antibiofilm activity, dentin-related outcomes, and biocompatibility or regeneration-related effects. Methods: PubMed/MEDLINE and ScienceDirect were systematically searched for English-language studies published from January 2015 to December 2025 using the following Boolean strategy: (“Nanoparticles” OR “Nano-based”) AND (“Root canal irrigant” OR “Antibiofilm”) AND (“Dentin surface” OR “Biocompatibility”). Eligible studies were original preclinical investigations evaluating nanoparticle-assisted irrigation or disinfection in extracted human-tooth models. After screening 695 records against predefined eligibility criteria, 12 studies were included. Results: Compared with conventional irrigants, nanoparticle-based systems showed promising antibacterial and antibiofilm effects, particularly against Enterococcus faecalis . Activation approaches, including photodynamic, sonic, and ultrasonic methods, were frequently associated with enhanced antimicrobial performance. Some studies also reported improved smear-layer removal, preservation of dentin ultrastructure, and favorable mechanical outcomes. In addition, several biology-related studies suggested acceptable cytocompatibility, growth-factor release, and improved healing-related responses under experimental conditions. Conclusion: Nanoparticle-assisted irrigation shows promising preclinical potential as an adjunct to conventional root canal disinfection. However, heterogeneity in study design and the absence of clinical evidence limit definitive conclusions and preclude routine clinical recommendations at present. Keywords: biocompatibility, biofilms, dental disinfectants, dentin, nanoparticles, root canal irrigation
Hussein et al. (Fri,) studied this question.