Ex vivo antimicrobial efficacy of the E ndo V ac ® system plus photodynamic therapy associated with calcium hydroxide against intracanal E nterococcus faecalis

Aim To evaluate the ex vivo efficacy of the EndoVac ® system and photodynamic treatment ( PDT ) as adjuncts to chemomechanical debridement associated with calcium hydroxide (Ca OH 2 ) in reducing the levels of intracanal Enterococcus faecalis . Methodology One hundred and twenty‐five sterile premolar teeth were conventionally accessed, prepared and then contaminated with E. faecalis ( ATCC 29212) for 30 days. Teeth were randomly divided into 4 groups: Control (chemomechanical debridement with conventional irrigation); Endovac (chemomechanical debridement with EndoVac ® system); PDT (chemomechanical debridement with conventional irrigation and PDT ) and Endovac+ PDT (chemomechanical debridement with EndoVac ® and PDT ). The irrigants used in all groups were 5.25% sodium hypochlorite and 17% EDTA . After treatment, an intracanal dressing (Ca OH 2 ) was applied in all canals for 7 days. Samples were obtained before (T1) and after the therapeutic procedures (T2) and, after intracanal medication (T3), plated onto BHI media and incubated (37 °C, 48 h) to determine the colony‐forming units ( CFU  mL −1 ). Results The overall mean cell counts ( CFU  mL −1 ) of E. faecalis were high at the initial contamination (T1). A significant reduction ( P  < 0.05) of E. faecalis mean counts was observed in all groups from baseline (T1) to both post‐therapy samplings (T2 and T3); no differences amongst the groups were detected. No significant change in bacterial counts from T2 to T3 was detected. Conclusion The adjunctive use of the EndoVac ® system and the photodynamic treatment, in combination or not, was as effective as the conventional chemomechanical debridement associated with Ca OH 2 on reducing the counts of intracanal E. faecalis .