Efficacy of the GentleWave System in the removal of biofilm from the mesial roots of mandibular molars before and after minimal instrumentation: An ex vivo study

Aim To compare the efficacy of Enterococcus faecalis biofilm removal using the GentleWave System (GWS) (Sonendo Inc, CA) on non‐instrumented versus minimally instrumented root canal systems. Methodology Thirty‐four mandibular molars were autoclaved and allocated to four groups: Negative control ( n = 5); positive control ( n = 5); Group 1: non‐instrumentation + GWS (NI + GWS) ( n = 12); and Group 2: minimal instrumentation + GWS (MI + GWS) ( n = 12). Of 34 samples, 24 samples with Vertucci type 2 configuration within the mesial root of each sample were allocated to Groups 1 and 2 and then matched based on the working length and root canal configuration. After inoculation of samples with E. faecalis for 3 weeks, the GWS was used on Group 1 without any instrumentation and Group 2 after instrumentation of mesial canals until size 20/06v. CFU and SEM analysis were used. Results Log 10 (CFU/mL) from the positive control, and Group 1 and 2 were 7.41 ± 0.53, 3.41 ± 1.54, and 3.21 ± 1.54, respectively. Both groups showed a statistically significant difference in the reduction of viable E. faecalis cells compared to the positive control (Group 1 [ p = .0001] and Group 2 [ p < .0001]), whilst showing no significant difference between the two tested groups ( p < .05). Conclusion The use of GWS on the non‐instrumented root canal system could be an effective disinfection protocol in removing the biofilm without dentin debris formation.