Objectives <p>This study evaluates the effectiveness of non-activated microbubble emulsions in removing biofilms in simulated minimally shaped root canals.</p> Materials and methods <p>Enterococcus faecalis biofilms were developed over three weeks in various sizes of 3D-printed root canal models. The biofilm removal efficiency of microbubble emulsions (MB) was compared with several irrigants, sodium hypochlorite (NaOCl), distilled water (DW), and hydrogen peroxide (HP), across different root canal dimensions (20.04, 20.06, 40.04, 40.06). Irrigation was performed using 2.5 mL of each solution for one minute. In the MB groups, the canal was filled with a single emulsion drop and left for one minute. We used confocal laser scanning microscopy and crystal violet colorimetric analysis to assess the effectiveness of biofilm eradication. Bonferroni tests and two-way ANOVA were employed to analyze the data.</p> Results <p>In narrow canals, MB emulsions demonstrated biofilm removal efficacy comparable to NaOCl (<i>P</i> &gt; .05). However, NaOCl was the most effective irrigation solution for wider canals (<i>P</i> &lt; .05). Canal size significantly influenced the biofilm removal efficacy in the MB group (<i>P</i> &lt; .05). Overall, both MB emulsions and NaOCl achieved better biofilm removal results than DW and HP (<i>P</i> &lt; .05).</p> Conclusion <p>The non-activated MBs have shown effective antibiofilm properties in narrow canals, making them suitable for a minimally invasive approach and indicating their potential role in developing improved irrigation protocols.</p> Clinical relevance <p>This study highlights the potential of microbubble emulsions as effective irrigants for minimally shaped root canals, supporting minimally invasive endodontic strategies.</p>