Assessment of Smear Layer Removal Using Biologically Active Irrigants: A Comparative In Vitro Study

Abstract

The presence of the smear layer after root canal instrumentation can hinder effective disinfection and sealing, compromising the long-term success of endodontic therapy. Conventional irrigants such as sodium hypochlorite and EDTA, while effective in cleaning, have shown limitations due to their cytotoxicity and potential for dentin erosion. This study aimed to comparatively assess the effectiveness of biologically active irrigants in removing the smear layer from root canal walls under in vitro conditions. Extracted single-rooted human teeth were prepared using standardized instrumentation techniques and divided into groups treated with various biologically active irrigants, including herbal extracts, enzymatic solutions, and nanoparticle-based agents, alongside conventional controls. Scanning Electron Microscopy (SEM) was employed to evaluate the cleanliness of the coronal, middle, and apical thirds of the canals. Statistical analysis revealed that certain biologically active irrigants achieved comparable or superior smear layer removal compared to traditional agents, particularly in the coronal and middle thirds, while demonstrating improved biocompatibility profiles. The findings suggest that biologically active irrigants represent a promising alternative for effective and safe canal debridement, potentially enhancing healing outcomes and minimizing adverse tissue responses.