Invitro Study About Antimicrobial Efficacy Of Different Irrigating Agentson Enterococcus Faecalisbiofilm Formation In Root Canal

Objectives: To compare the antimicrobial effect ofdifferent irrigating agents to disinfecthuman root canals that had been contaminated with Enterococcus faecalis, to evaluate the antimicrobial activity of irrigating solutions residual against Enterococcus faecalis biofilms formation, aiming to provide a better strategy to choose irrigating agents for clinician.Material and methods: Part I :82 extracted human one root canal premolar teeth were cleaned and autoclaved, 2 autoclaved samples were transferred to controls. Enterococcus faecalis was used to contaminate the root canals of the rest of the samples for 28 days. During biomechanical instrumentation, the root canal was irrigated with 4 different irrigating agents.The bacteria samples were collected with sterile paper points before and after the instrumentation to F1、F2、F3. Part II : 40 samples that have been instrumented and autoclaved again were randomly divided into 4 groups with 10 in each group, and treated with four different irrigating in 30 minutes. After that, Enterococcus faecalis was used to contaminate the root canals, the bacteria samples were collected with sterile paper points after 2 hours、6 hours、24 hours、48 hours.Results: Part I :Statistical analysis of the data using K-W test shows that the group using 5% Na OCl and 2%CHX was significantly more effective against Enterococcus faecalis than the other groups.Part II :5% Na OCl and 2%CHX groups showed a better residual activity than other 2 groups.Conclusions: Na OCl is still the most important irrigating solutions. CHX cannot take place of the Na OCl, but it can be a better choice using it after all the biomechanical instrumentation, for its long time Substantivity to achieve residual antimicrobial activity. Ultrasound Devices is recommend.