Antibacterial efficacy of nisin, calcium hydroxide, and triple antibiotic paste in combination with chitosan as an intracanal medicament against Enterococcus faecalis – An in vitro study
VS Harshitha, MA Ranjini, RoopaR Nadig
Abstract
<b>Aims:</b> Evaluate and compare antibacterial efficacy of nisin, calcium hydroxide (Ca (OH)<sub>2</sub>), and Triple antibiotic paste (TAP) mixed with distilled water and chitosan as an intracanal medicament on <i>Enterococcus faecalis</i> after 1<sup>st</sup> and 7<sup>th</sup> day.<br><b>Settings and Design:</b> Experimental <i>in vitro</i> study.<br><b>Materials and Methods:</b> One hundred and twenty Decoronated single-rooted premolars were prepared and autoclaved. Specimens were placed in brain heart infusion (BHI) broth of a 24 h old <i>E. faecalis</i> (ATCC 29212) suspension. The canal was infected for 21 days, followed by grouping as-Group 1: Nisin + distilled water; Group 2: Nisin + 2% chitosan; Group 3: Ca (OH)<sub>2</sub> + distilled water; Group 4: Ca (OH)<sub>2</sub> + 2% chitosan; Group 5: TAP + distilled water; Group 6: TAP + 2% chitosan and were incubated for 1 and 7 days. Dentin scrapings from 10 specimens at each time interval were transferred into BHI broth and incubated, Serially diluted and colony-forming unit (CFU) count was assessed after 1<sup>st</sup> and 7<sup>th</sup> day.<br><b>Statistical Analysis Used:</b> Kruskal–Wallis test to compare mean CFUs after day 1 and day 7. Mann–Whitney <i>post hoc</i> Analysis to estimate significance. Wilcoxon Signed-Rank Test to compare mean CFUs between day 1 and day 7.<br><b>Results:</b> After 1 day, Group 6 showed least CFUs than other groups and highest CFUs was with Group 3. There was no difference statistically when Group 5 and Group 2 were compared. After 7 days, Group 6 showed least CFUs than other groups with no significant difference between Group 1 and Group 5 as well as no significant difference between Group 2, Group 5 and Group 6.<br><b>Conclusions:</b> TAP with chitosan can be the medicament of choice for 1-day placement and was equivalent to nisin with chitosan combination after 7 days.<br>