Additive Effect of Photoactivated Disinfection on The Antibacterial Activity of Qmix 2in1 Against 6‑Week Enterococcus Faecalis Biofilms: An In Vitro Study

Abstract

Background: Evaluation of the additive effect of photodynamic therapy (PDT) on the antibacterial activity of 2.5% sodium hypochlorite (NaOCl) and QMix against 6‑week Enterococcus faecalis biofilms contaminated root canals. Aims: To establish the most suitable irrigant for eradication of 6‑week E. faecalis biofilms. Settings and Design: In vitro study. Materials and Methods: A 6-week E.faecalis (ATCC 29212) biofilm was formed in 190 extracted teeth that were subsequently subjected to irrigation protocols as follows. Group A1: normal saline, Group A2: 2.5% NaOCl, Group A3: QMix, Group B1: normal saline and photoactivated disinfection (PAD), Group B2: 2.5% NaOCl and PAD, Group B3: QMix and PAD, Group C: no irrigation. For PAD, irradiation was done three times for 5 s each with 10 s interval on continuous mode with a 980 nm diode laser. Samples from the root canals were collected and plated onto brain heart infusion agar plates to determine the colony‑forming unit/ml. Statistical Analysis Used: One‑way ANOVA, post hoc Tukey’s honest significant difference test. Results: Maximum percentage of disinfection (99%) was seen in Group B2 (NaOCl with PDT), which was similar to Groups A2 (97.6%) and B3 (98.8%) (P < 0.0001). Conclusions: NaOCl with PDT gave maximum disinfection.