Bacteria Elimination in Retreatment Cases Using Different Disinfection Techniques

Enterococcus Faecalis Elimination in Retreatment Cases Using Passive Ultrasonic Irrigation (PUI), Manual Dynamic Activation (MDA) and Photodynamic Therapy (PDT): a Randomized Clinical Trial

Nonsurgical root canal retreatment may become essential when the initial endodontic treatment fails because of the persistent intracanal or extracanal infections.It has been stated that the one of the main cause of posttreatment disease is the persistent or reintroduced microorganism such as enterococcus faecalis. Supplementary disinfection techniques such as irrigation agitation methods can help elimination of bacteria from root canal systems. The aim of this in vivo study was to compare the effect of passive ultrasonic irrigation, manual dynamic activation and photodynamic therapy in reducing bacterial load in endodontic retreatment cases with periradicular lesion by using polymerase chain reaction (PCR)in a single visit root canal treatment.

Thirty-six teeth with a single root and a single canal with posttreatment apical periodontitis which needed retreatment were selected for this study. Teeth were randomly divided into 3 groups according to the supplementary disinfection techniques used: Passive ultrasonic irrigation, Manual dynamic activation and Photodynamic therapy. Microbiological samples were taken before any intervention, after conventional chemo-mechanical preparation, and after disinfection techniques with sterile paper points and held in thioglycollate broth, and then were transferred to the microbiological laboratory. The amounts of e.faecalis in these samples was measured by using PCR.

Irrigation solution was ultrasonically activated in the canal for 1 minute by using IrriSafe tip coupled to an ultrasonic device with VDW Ultra .

Irrigation solution was activated with a well-fitting a ProtaperNext X3 gutta-percha point placed to working length was then moved in push - pull motions at a rate of 100 strokes/per minute

Root canal was filled by 0.5 mL of 0.01% methylene blue (MB) solution for 5 minutes, then radiated by the light supply of a diode laser AMD picasso with a wavelength of 810 nm for 40 seconds (0.2 W).

Bacteria samples were taken at 3 step; before any intervention, after chemomechanical preparation, and after applying supplementary disinfection techniques

Inclusion Criteria: Patients with no clinical symptoms Endodontically treated teeth Single rooted teeth Exclusion Criteria: Teeth with fractured instrument, resorption, perforation, ledge, over fillings Periodontal pockets deeper than 4 mm

Asnaashari M, Godiny M, Azari-Marhabi S, Tabatabaei FS, Barati M. Comparison of the Antibacterial Effect of 810 nm Diode Laser and Photodynamic Therapy in Reducing the Microbial Flora of Root Canal in Endodontic Retreatment in Patients With Periradicular Lesions. J Lasers Med Sci. 2016 Spring;7(2):99-104. doi: 10.15171/jlms.2016.17. Epub 2016 Mar 27.

Rodrigues RC, Antunes HS, Neves MA, Siqueira JF Jr, Rocas IN. Infection Control in Retreatment Cases: In Vivo Antibacterial Effects of 2 Instrumentation Systems. J Endod. 2015 Oct;41(10):1600-5. doi: 10.1016/j.joen.2015.06.005. Epub 2015 Jul 30.