Enterococcus Faecalis is the most common facultative anaerobic bacteria isolated from both secondary and persistent root canal infections. E. faecalis invades and adheres to the dentinal tubules with a depth of penetration ranging from 500 to 1000 μm, and has the ability to survive in harsh environmental conditions due to its potential to transform into the viable but noncultivable (VBNC) state. This Paper highlights the use of Nisin, Calcium Hydroxide and Triple Antibiotic Paste each as an intracanal medicaments combined with propylene glycol, CHX and saline used as a vehicle. Nisin, a chemical commonly used as a food preservative (meat and dairy products), is recently recommended for use as an intracanal medicament. Discovered in 1928, it is a naturally occurring antimicrobial cationic peptide, produced by Streptococcus lactis subspecies lactis. Propylene glycol which was suggested by Laws in 1962 has been evaluated for its possible use as a vehicle in the field of endodontics. It permits the release of calcium and hydroxyl ions essential for the therapeutic action. It has been found to be antibacterial, nonirritating to the periapical tissue. 2% CHX is effective in completely eliminating E. Faecalis from the dentinal tubules up to a period of 15 days attributed to its substantive antimicrobial activity.This study aims to see the combined effect of Nisin, Calcium Hydroxide and Triple Antibiotic Paste when mixed with different vehicle.

1. Bilgi PS, Shah NC, Mehta J. COMPERATIVE Evaluation Of Mixture Of Calcium Hydroxide and Chlorhexidine, with Triple Antibiotic Paste and Combination Of Calcium Hydroxide, Chlorhexidine, and Lycopene on Incidence of Interappointment Flare-up: An in vivo Study. Int J Clin Dent Res 2017;1(1):10-14.
2. Mitthra S, Abraham TA, Subbiya A et al. Antibacterial Efficacy of Nisin and Calcium Hydroxide with a Proton Pump Inhibitor as an Intracanal Medicament. World J Dent 2018;9(2):111-1.
3. Sirén EK, Haapasalo MP, Waltimo TM, Ørstavik D. In vitro antibacterial effect of calcium hydroxide combined with chlorhexidine or iodine potassium iodide on Enterococcus faecalis. Eur J Oral Sci 2004 Aug;112(4):326-331.
4. H. Robert, F. R. Liewehr, T. B. Buxton, and J. C. McPherson III, “Apical diffusion of calcium hydroxide in an in vitro model,” Journal of Endodontics,2005; 31(1): 57–60.
5. Gomes BP, Vianna ME, Sena TN, Zaia AA, Ferraz CC, Filho FJS. In vitro evaluation of the antimicrobial activity of calcium hydroxide combined with chlorhexidine gel used as intracanal medicament. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2006 Oct;102(4):544–550.
6. C. Gomes Camoes, M. R. Salles, and O. Chevitarese, “Ca ˜ 2+ diffusion through dentin of Ca(OH)2 associated with seven different vehicles,” Journal of Endodontics, 2003; 29(12): 822–825.
7. Wagner C, Barth VC Jr, de Oliveira SD, Campos MM. Effectiveness of the proton pump inhibitor omeprazole associated with calcium hydroxide as intracanal medication: an in vivo study. J Endod 2011 Sep;37(9):1253-1257.
8. Bhat KS, Walvekar SV. Evalution of bactericidal property of propylene glycol for its possible use in endodontics. Arogya J Health Sci. 1975;1:54–9.
9. Ferreira FB, Torres SA, Rosa OP, Ferreira CM, Garcia RB, Marcucci MC, et al.Antimicrobial effect of propolis and other substances against selected endodontic pathogens. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2007;104:709-16. 
10. Turner SR, Love RM, Lyons KM. An in-vitroinvestigation of the antibacterial effect of nisin in root canals and canal wall radicular dentine. Int Endod J 2004;37:664-71
11. Mistry KS, Sanghvi Z, Parmar G, Shah S. The antimicrobial activity of Azadirachta indica, Mimusops elengi, Tinospora cardifolia, Ocimumsanctum and 2% chlorhexidine gluconate on common endodontic pathogens: An in vitro Eur J Dent. 2014;8:172–7
12. Hoshino E, Kurihara-Ando N, Sato I, Uematsu H, Sato M, Kota K, et al. In-vitro antibacterial susceptibility of bacteria taken from infected root dentine to a mixture of ciprofloxacin, metronidazole and minocycline. Int Endod J. 1996;29:125–30.
13. Evans M, Davies JK, Sundqvist G, Figdor D. Mechanisms involved in the resistance of Enterococcus faecalisto calcium hydroxide. Int Endod J 2002;35:221-8.
14. Kontakiotis EG, Tsatsoulis IN, Papanakou SI, Tzanetakis GN. Effect of 2% chlorhexidine gel mixed with calcium hydroxide as an intracanal medication on sealing ability of permanent root canal filling: A 6-month follow-up. J Endod 2008;34:866-70.
15. Tong Z, Zhang Y, Ling J, Ma J et al. (2014) An In VitroStudy on the Effects of Nisin on the Antibacterial Activities of 18 Antibiotics against Enterococcus faecalis.PLoS ONE 2014; 9:1-18
16. Hemadri M, Thakur S, Sajjan G. Nisin vs calcium hydroxide - Antimicrobial efficacy on Enterococcus faecalis- An in-vitro Int J Contemp Dent 2011;2:55-61
17. Bozdogan B, Esel D, Whitener C, Browne FA, Appelbaum PC. Antimicrobial susceptibility of a vancomycin-resistant Staphylococcus aureusstrain isolated at the Hershey medical center. J Antimicrob Chemother 2003;52:864-8.
18. Delgado RJ, Gasparoto TH, Sipert CR, Pinheiro CR, Moraes IG, Garcia RB, et al.Antimicrobial effects of calcium hydroxide and chlorhexidine on Enterococcus faecalis. J Endod 2010;36:1389-93. 
19. Mohammadi Z, Abbott PV. The properties and applications of chlorhexidine in endodontics. Int Endod J 2009;42:288-302.
20. Figdor D, Gulabivala K. Survival against the odds: Microbiology of root canals associated with post-treatment disease. Endod Top 2011;18:62-77.
21. Greenstein G, Berman C, Jaffi n R. Chlorhexidine an adjunct to periodontal therapy. J Periodontol 1986;57:370-6.
22. Janaina Corazza Montero et al. Asessment of ion diffusion from a calcium hydroxide-propolis paste through dentin. Braz Oral Res (São Paulo) 2012 Jul-Aug;26(4):318-22
23. Vahdaty A, Piford TR, Wilson RF. Effi cacy of chlorhexidine in disinfecting dentinal tubules in vitro. Endod Dent Traumatol 1993;9:243-8.
24. Evans M, Davies JK, Sundqvist G, Figdor D. Mechanisms involved in the resistance of Enterococcus faecalis to calcium hydroxide. Int Endod J 2002;35:221-8.
25. Kuipers OP, Rollema HS, Yap WMGJ, Boot HJ, Siezen RJ, de Vos WM. Engineering dehydrated amino acid residues in the antimicrobial peptide Nisin. Journal of Biological Chemistry 1992; 267, 24: 340-346.
26. Bose R, Nummikoski P, Hargreaves K. A retrospective evaluation of radiographic outcomes in immature teeth with necrotic root canal systems treated with regenerative endodontic procedures. J Endod. 2009;35:1343–9.
27. Jack RW, Tagg JR, Ray B. Bacteriocins of Grampositive bacteria. Microbiological Reviews 1995; 59:171-200.
28. Hurst A. function of Nisin and Nisin like basic proteins in the growth cycle of streptococcus lactis. Nature 1967; 214:1232-1234.
29. Lin S, Zukerman O, Weiss EI, Mazor Y, Fuss Z. Antibacterial efficacy of a new chlorhexidine device to disinfect dentinal tubules. J Endod 2003; 29(6): 416-418.
30. Komorowski R, Grad H, Wu XY, Friedman S. Antimicrobial substantivity of chlorhexidine treated bovine root dentin. J Endod 2000 Jun;26(6):315-317.
31. Lage Marques JLS, Conti R, Antoniazzi JH, Guth I. Avaliação da velocidade de dissociação iônica do hidróxido de cálcio associado a diferentes veículos/ In vitro assessment of the ionic dissociation velocity of clcium hydroxide to diferente vehicles. Rev odontol Univ São Paulo. 1994 Apr-Jun;8(2):81-7.
32. Williams JM, Trope M, Caplan DJ, Shugars DC. Detection and quantitation of E. faecalis by real-time PCR (qPCR), reverse transcription-PCR (RT-PCR), and cultivation during endodontic treatment. J Endod 2006 Aug;32(8):715-721.
33. Poggio C, Colombo M, Scribante A, Sforza D, Bianchi S. In vitro antibacterial activity of different endodontic irrigants. Dent Traumatol 2012 Jun;28(3):205-209.
34. Turk BT, Sen BH, Ozturk T. In vitro antimicrobial activity of calcium hydroxide mixed with different vehicles against Enterococcus faecalis and Candida albicans. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009 Aug;108(2):297-301.
35. Narayanan LL, Vaishnavi C. Endodontic microbiology. J Conserv Dent 2010 Oct-Dec;13(4):233-239.

Dr Pallavi Mittal

PG Final Year Student, Department of Conservative Dentistry and Endodontics, Career Post Graduate Institute of Dental Sciences and Hospital, Lucknow, UP, India