Antimicrobial Efficacy of Dual Wavelength Lasers-Activated Irrigation in Root Canal Therapy ( In vitro Study)

This study evaluated the antimicrobial efficacy of Erbium chromium and diode lasers, with or without irrigant, against Enterococcus faecalis (E. faecalis) biofilm. Sixty-five single rooted teeth were incubated with E. faecalis and then treated either with: 5.25% sodium hypochlorite (Group 1); 5.25% sodium hypochlorite then 2% chlorhexidine (Group 2); dual laser with saline (Group 3); dual laser with 5.25% sodium hypochlorite (Group 4); or dual laser with 5.25% sodium hypochlorite then 2% chlorhexidine (Group 5). Positive control teeth were incubated with E. faecalis but received no antimicrobial treatment while negative control teeth were left uninfected. Decontamination was assessed by estimation of colony forming units before and after irrigation using a manual colony counter and Open CFU software. Treatments 1, 2, 4 and 5 achieved 92 to 100% decontamination with no significant difference between these treatments (P > 0.005). Dual laser with saline resulted in significantly less disinfection (75%) than the other treated groups (P < 0.005).