Ashish Choudhary, Riyaz Farooq, Sachin Chadgal, Aamir Rashid Purr4, Fayaz Ahmed Aangar
BACKGROUND:Smear layer formed by mechanical action of endodontic instruments is the potential source of microbial infection. Various chelating actions have been used for managing the smear layer but none of them showed promising results at the apical third of root canal. The purpose of this study was to evaluate the intracanal smear layer removal efficacy of 10% citric acid, 7% maleic acid and 17% EDTA at the apical third area of single rooted teeth when irrigated with apical negative pressure system.
METHODS; Eighty single-rooted human premolars with straight canals and fully formed apex were selected. Samples were randomly divided into two groups- groups I and II of 40 patients each, depending on the method of irrigation. Root canals were then prepared with Pro Taper rotary files up to size F4. The samples were irrigated with 5% NaOCl solution during the preparation of root canals with a 30-gauge side vented, closed end needle and EndoVac in group I and II respectively. The samples were again divided into four different subgroups (n=10 each) in each group depending upon the chelating agent (distilled water, 17% EDTA, 10% critic acid, 7% maleic acid) used for smear layer removal in the final irrigation procedure. The apical third of the root canal was examined using scanning electron microscope at 1000X magnification as it was the area of concern in the present study. Analysis of variance (ANOVA) and Least Significant Difference (LSD) tests were employed for intra-group analysis of data. For inter group analysis, Student's independent t-test was used. A p-value of less than 0.05 was considered statistically significant.
RESULTS: 10% citric acid and 7% maleic acid were able to remove the smear layer at the apical third, when irrigated with EndoVac, significantly better than all the groups tested. EndoVac did remove the smear layer significantly better than traditional needle irrigation but was not able to remove it completely at the apical third.
CONCLUSIONS Use of EndoVac along with chelating agents, benefits smear layer removal from root canals.