COMPARATIVE EVALUATION OF DIFFERENT IRRIGATION AGITATION METHODS IN BACTERIAL REDUCTION OF OVAL SHAPED CANALS: AN IN VITRO STUDY

Abstract

INTRODUCTION: Thorough cleaning of the pulp space is a challenging task. The mechanical instrumentation alone is usually not sufficient to completely debride the canals, and therefore, it requires the chemical action of irrigants also to disinfect the difficult to reach areas. Sodium hypochlorite is the most used irrigating solution in endodontics, because its mechanism of action causes biosynthetic alterations in cellular metabolism and phospholipid destruction, formation of chloramines that interfere in cellular metabolism, oxidative action with irreversible enzymatic inactivation in bacteria, and lipid and fatty acid degradation.

MATERIAL AND METHOD: : Fourty extracted human teeth with similar dimensions were selected. Access cavities were prepared and the root canals were instrumented using Heroshaper Gold   (25/4

%). The root canals were then contaminated with an E. faecalis suspension following incubation for thirty days. The contaminated roots were divided into three experimental groups (n=10) according to the  irrigant  agitation  protocol  (Passive  ultrasonic  irrigation  XP  ENDO  Finisher  Group and sonic irrigation), in addition to a positive control group (n=5) and a negative control group (n=5). Microbiological samples were taken from the root canals before instrumentation (S1), after instrumentation (S2) and after the final irrigation protocol (S3). The samples were assayed and incubated for 48 hours in order to obtain the residual titer of E. faecalis cells. Viable cells were quantified by colony-forming units (CFU) measurement. The collected data was submitted to statistical analysis descriptive quantitative data was expressed in mean and standard deviation respectively. Data normality was checked by using Shapiro – Wilk test. Confidence interval  is set at 95% and probability of alpha error (level of significance) set at 5%. Power of the study set at 80%.

RESULTS: Result demonstrated that all final agitation protocols were effective in reducing the bacteria with more number of reduction in XP endo finisher 0.1 (0.31) and passive ultrasonic irrigation 0.1 (0.31) followed by Endoactivator 0.4 (0.51).

CONCLUSION: All additional cleaning techniques improved the disinfection, regardless of the region under study . XPEFR was more effective than PUI and EAS. However, none of the techniques was capable to render the root canals completely free of microorganism