A scanning electron microscope evaluation of efficacy of sodium hypochlorite and Allium sativum in smear layer removal in root canals with the use of modified evacuation system: An ex vivo study

CONTEXT: Sodium hypochlorite (NaOCl) is the most widely used endodontic irrigant. Although it fulfills most of the requisites of an ideal irrigant, it has certain drawbacks, chiefly severe soft-tissue damage. Allium sativum (garlic extract) is a proven antimicrobial agent that has the ability to dissolve inorganic tissue with minimal toxicity. However, its ability to remove smear layer (SL) is not known. Conventional hand-held syringe irrigation is ineffective in removing canal debris. The use of newer irrigation systems is limited owing to their high cost. Modified evacuation system (MES) may prove to be an effective yet economical alternative. AIMS: This study aims to evaluate the SL removing capacity of garlic extract as an alternative to 5% NaOCl and the use of modified evacuation system for removal of irrigant along with debris from root canals. SETTINGS AND DESIGN: Sixty-eight single-rooted mandibular premolars were divided into 8 Groups: Two control Groups A and B (4 samples each) and six experimental Groups C to H (10 samples each). Garlic extract was prepared at a concentration of 64 mg/ml. MES was set up using 21-gauge flat-end needle fixed onto chair side high-volume evacuation system. SUBJECTS AND METHODS: Control groups were irrigated with normal saline, Groups C and D with 5% NaOCl and 17% ethylenediaminetetraacetic acid (EDTA), Groups E and F with garlic extract and 17% EDTA and Groups G and H with plain garlic extract. MES was used in Groups B, D, F, and H. Scanning electron microscope analysis was done to view SL at coronal, middle, and apical thirds. STATISTICAL ANALYSIS USED: Chi-square test. RESULTS: Groups A and B showed least scores. At coronal and middle thirds, Group D shows better results, followed by Groups F and H. Apically, Group F showed better results. Groups C and H, and E and G showed similar results. All groups with MES showed better results. CONCLUSIONS: A. sativum has an SL removal capacity. MES is effective in debris removal.