IADR Abstract Archives
Effect of Ultrasonically-Activated Irrigation Protocols Used for Regenerative Endodontics on Removal of Dual Species Biofilm in a Three-Dimensionally Printed Tooth Model
Objectives: To evaluate the influence of ultrasonically activated irrigants in concentrations used for REPs for removal of dual-species biofilm from three-dimensionally printed tooth models with attached dentine samples.
Methods: Seventy-two three-dimensionally printed teeth models were fabricated with a standardized slot in the apical third of the root to achieve precision fit of a human root dentine specimen. Dual species biofilms including Enterococcus faecalis and Streptococcus mutans were
developed in the root canal for three weeks. Models with dentine specimens were randomly assigned into 5 groups according to the irrigation protocol: G1 infected root canals irrigated with distilled water to serve as controls; G2: 1.5% NaOCl for 5 min; G3: 1.5% NaOCl + passive
ultrasonic irrigation (PUI) for 30 secs; G4: 3% NaOCl for 5 min; G5: 3% NaOCl + PUI for 30 sec. Bacterial reduction was determined by colony-forming unit (CFU) counting (n = 12/G), whilst biofilms were analyzed using field emission scanning electron microscopy in additional
samples.
Results: All experimental groups were associated with a significant reduction in the CFU count compared with the control group (p<0.05). When compared with the corresponding control, the highest reduction in bacterial count was obtained with G5 (3% NaOCl + PUI for 30 sec)
followed by G4 (3% NaOCl), then G3 (1.5% NaOCl + PUI for 30 sec), and finally G2 (1.5% NaOCl).
Conclusions: The results of this study suggest that a 3D-printed tooth model can be used to effectively analyze the antimicrobial effects of different irrigation protocols on dual species biofilm. The use of NaOCl in concentrations used for regenerative endodontics can effectively remove bacterial biofilms. Furthermore, the use of PUI did not significantly enhance antibacterial effects of NaOCl.
Methods: Seventy-two three-dimensionally printed teeth models were fabricated with a standardized slot in the apical third of the root to achieve precision fit of a human root dentine specimen. Dual species biofilms including Enterococcus faecalis and Streptococcus mutans were
developed in the root canal for three weeks. Models with dentine specimens were randomly assigned into 5 groups according to the irrigation protocol: G1 infected root canals irrigated with distilled water to serve as controls; G2: 1.5% NaOCl for 5 min; G3: 1.5% NaOCl + passive
ultrasonic irrigation (PUI) for 30 secs; G4: 3% NaOCl for 5 min; G5: 3% NaOCl + PUI for 30 sec. Bacterial reduction was determined by colony-forming unit (CFU) counting (n = 12/G), whilst biofilms were analyzed using field emission scanning electron microscopy in additional
samples.
Results: All experimental groups were associated with a significant reduction in the CFU count compared with the control group (p<0.05). When compared with the corresponding control, the highest reduction in bacterial count was obtained with G5 (3% NaOCl + PUI for 30 sec)
followed by G4 (3% NaOCl), then G3 (1.5% NaOCl + PUI for 30 sec), and finally G2 (1.5% NaOCl).
Conclusions: The results of this study suggest that a 3D-printed tooth model can be used to effectively analyze the antimicrobial effects of different irrigation protocols on dual species biofilm. The use of NaOCl in concentrations used for regenerative endodontics can effectively remove bacterial biofilms. Furthermore, the use of PUI did not significantly enhance antibacterial effects of NaOCl.