Efficacy of Supplementary Irrigation Methods Against Bacterial Biofilm‐Infected Root Canals Prepared With Minimally Invasive and Conventional Techniques

This study evaluated the effectiveness of the GentleWave system (GWS), laser-activated irrigation (LAI), ultrasonic-activated irrigation (UAI) and sonic irrigation (SI) in removing a three-species biofilm from infected root canals prepared using minimally invasive techniques (MIT) and conventional instrumentation techniques (CIT). One hundred and ten single-canalled mandibular premolars were infected with the biofilm and assigned to five groups based on the supplementary irrigation method used. Biofilm removal was assessed using confocal laser scanning microscopy and scanning electron microscopy. In the CIT group, GWS resulted in a significantly higher proportion of dead cells compared to UAI and SI (p < 0.05), with no significant difference between GWS and LAI. In the MIT group, no significant differences were observed among the irrigation methods (p > 0.05). Although none of the approaches completely eliminated the biofilm, GWS and LAI were more effective than UAI and SI.