An in vitro comparison of antibacterial effects of four different root canal irrigation method in root canals infected with Enterococcus faecalis

The aim of conventional endodontic treatment is to clean root canal system, shape in accordance with original root canal form, disinfect and fill the root canal with filling materials hermetically. The complex anatomy of the root canal system reduces the treatment outcome in significant rate preventing to clean and shape root canal system optimally. Hence, cleaning root canals from infected pulp and dentin tissue holds to be a current issue of endodontics and numerous studies is being performed concerning this issue. Apical periodontitis is an inflammatory disease caused by microorganisms infecting the root canal. Endodontic infections arise from bacteria, fungi and viruses. They play a big role in the pathogenesis of apical periodontitis. It has a great importance for root canal flora which includes Enterococcus faecalis and persistent microorganisms to be cleaned completely. It is well known only mechanical preparation is insufficient to clean root canal system and there can be untouched dentinal walls by any file up to %35. These scientific facts indicates that irrigation root canals with antimicrobial irrigation solutions takes great importance in especially mechanically untouched areas. The purpose of the study was to compare the antibacterial effect of four different currently generated rootcanal irrigation methods in root canals enfected with E. faecalis. In the present study, 105 extracted single rooted and canaled human upper and lower incisor, canin and premolars were used. 20 samples were distrubuted to each four experimental and a positive control group. 5 teeth were used in SEM imaging. Groups were generated respectively in tihs way: Group 1: Hawe irrigation probe side-vented needle, Grup 2: EndoActivator, Grup 3: EndoVac, Grup 4: SAF ve Grup 5: (+) control group. VII After shaping with hand instruments root canals were infected with E. faecalis and first samples (S1) was taken, then the mechanic preparation was done with rotary instruments and irrigation systems. After then second samples (S2) were taken. Intra and inter group analyses were performed. Statistical analyses was performed by SPSS (Statistical package for social sciences) for windows 15.0 program. While study data were being evaluated the convenience of the parameters to normal distribution was evaluated with Kolmogorov-Smirnov test and parameters weren't in compliance with normal distribution. Since study data were evaluated in intergoup comparisons of parameters Kruskal Wallis test was used. Bonferroni correction Mann Whitney U test was performed to determine the group which cause difference. Wilcoxon signed test was used to compare intragroup analyses of parameters. The significance was evaluated at the level of p<0.05. According to obtained data, the number of bacteria observed in positive control group after irrigation was significantly higher from side-vented needle, EndoVac, EndoActvator and SAF (p<0.005) (p=0.001). There was no significant difference between the number of bacteria after irrigation in other groups. The decrease percentage of the number of bacteria in positive control group was significantly lower than side-vented needle, EndoVac, EndoActivator and SAF (p<0.005). There was no significant difference between the experimental groups in terms of decrease percentage after irrigation (p>0.05). According to the result of the study there was no staistically difference observed between irrigation systems used in terms of antibacterial effect. Keywords: Irrigation methods, Hawe irrigation probe, EndoActivator, EndoVac, SAF, Enterococcus faecalis.