Combination effects of Nd:YAP laser and DNase I on dual‐species biofilm removal in a simulated lateral canal model: An in vitro study

This study aimed to investigate the efficacy of a novel combination of the neodymium-doped yttrium aluminum perovskite (Nd:YAP) laser and deoxyribonuclease I (DNase I) in eliminating dual-species biofilms from dentinal surfaces using a three-dimensional (3D)-printed lateral canal model. A computational fluid dynamics model was used to assess the impact of needle insertion depth on irrigant flow within the lateral canal model. Enterococcus faecalis and Fusobacterium nucleatum biofilms were cultured on dentin discs. Scanning electron microscopy and confocal laser scanning microscopy (CLSM) were used to investigate the influence of Nd:YAP laser and DNase I on the antimicrobial activity of 1% sodium hypochlorite (NaOCl). The CLSM results demonstrated a significant reduction in the formation of dual-species biofilms among viable bacteria treated with the combination of Nd:YAP laser and DNase I, compared to other treatment groups. As the needle insertion depth decreased, the irrigant velocity in the lateral canal decreased, resulting in the attachment of a greater number of viable bacteria. The combination of Nd:YAP laser and DNase I effectively addresses the limitations of single supplementary treatment by enhancing irrigant penetration and biofilm disruption within the lateral canal model, presenting a promising strategy for in vitro disinfection of lateral canal structures.