Introduction

Mechanical instrumentation is the core method for bacterial reduction in the infected root canal, but achieving bacteria-free root canals still proves to be difficult.² Various studies have demonstrated that mechanical preparation with hand instruments and irrigation with saline cannot predictably eliminate the bacteria from the infected root canals.^3-5 Therefore, the current focus of interest has been the use of irrigating solutions with strong antibacterial activity as the necessary supplement to mechanical preparation.

Even after meticulous mechanical procedures along with the use of irrigating solutions, some bacteria can still be recovered from the canals. The genera that most frequently persist include Enterococci, Staphylococci and Gram-negative enteric rods. Enterococcus faecalis, a Gram-positive facultative anaerobe, is commonly found in the root canals of failing endodontically treated cases.⁷ 

The persistence of these microorganisms in the root canals, even after the use of irrigating solutions suggests that the choice of the solution used is largely determined still on empirical data. There is a strong relationship between the long-term treatment success and root canal filled after negative culture in teeth with apical periodontitis. Studies reveal complete periapical healing in 94% of teeth with apical periodontitis that yielded negative culture after root canal instrumentation. In contrast, the samples with positive culture before root canal obturation had only 68% of complete periapical healing⁽³⁾.

1. Spratt DA, Pratten J, Wilson M, Gulabivala K. An in vitro evaluation of the antimicrobial efficacy of irrigants on biofilms of root canal isolates. Int Endod J. 2001;34(4):300–307. [PubMed]
2. Dalton BC, Orstavik D, Phillips C, Pettiette M, Trope M. Bacterial reduction with nickel-titanium rotary instrument-tation. J Endod. 1998;24(11):763–767.[PubMed]
3. Siqueira JF Jr, Lima KC, Magalhaes FA, Lopes HP, de Uzeda M. Mechanical reduction of the bacterial population in the root canal by three instrumentation techniques. J Endod. 1999;25(5):332–335. [PubMed]
4. Pataky L, Ivanyi I, Grigar A, Fazekas A. Antimicrobial efficacy of various root canal preparation techniques: an in vitro comparative study. J Endod. 2002; 28(8) :603–605. [PubMed]
5. Haapasalo M, Endal U, Zandi H, Coil JM. Eradication of endodontic infection by instrumentation and irrigation solute-ons. Endod Topics. 2005;10(1):77–102.
6. Rocas IN, Siqueira JF Jr, Santos KR. Association of Enterococcus faecalis with different forms of periradicular diseases. J Endod. 2004;30(5):315–320. [PubMed]
7. Bystorm A, Happonen RP, Sjogren U, Sundquist G. Healing of periapical lesions of pulpless teeth after endodntic treatment with controlled asepsis. Endod Dent Traumatol 1987; 3: 50-63.
8. Schirrmeister JF, Liebenow AL, Pelz K, et al. New bacterial compositions in rootfilled teeth with periradicular lesions. J Endod 2009;35:169–74.
9. Rocas IN, Sequiera JF, Samos KRN. Association of Enterococcus Faecalis with different forms of periradicular disease. J Endod 2004, 30: 315-20.
10. Sundqvist G. Taxonomy Ecology and pathogenicity of the root canal flora, Oral Surg Oral Med Oral Pathol 1994: 78(4) 522-30.
11. Harrison J. W .Irrigation of the root canal system. DCNA; 28, 797-808
12. Bystorm A, Sundquist G. Bacteriologic evaluation of the efficacy of mechanical root canal instrumentation in Endodontic therapy. Scand J dent Res 1981; 89; 321-8
13. Gordon TM, Dmato D, Christner P. Solvent effect of various dilutions of sodium hypochlorite on vital and necrotic tissue. J Endod 1981; 7: 466-9.
14. Jeansonne J. Micheal and White R Robert , A comparison of 2.0% Chlorhexidine gluconate and5.2% Sodium hypochlorite as antimicrobial irrigants. J Endod 1994; 20: 276-78.
15. Seal GJ, Ng L-Y, Spratt D, Bhatti M, Gulabivala K. An in vitrocomparison of bacterial efficacy of lethal photosens-itisation or sodium hypochlorite irrigation on Streptococcus intermedius  biofilms in root canals. Int Endodont J. 2002;35:268–274. [PubMed]. Steinberg D, Heling I, Daniel I, Ginsburg I. Antibacterial synergistic effect of chlorhexidine and hydrogen peroxide against Streptococcus sobrinus, Streptococcus faecalis, Staphylococcus aureus. J Oral Rehab. 1999;26:151–152. [PubMed]
16. Kaufman AY. Facial emphysema caused by hydrogen peroxide irrigation: report of case. J Endodont. 1981;7(10):470– 472. [PubMed].
17. George Sakoulas, Arnold S. Bayer ,Joseph Pogliano. Ampicillin Enhances Daptomycin – and Cationic Host Defense Peptide-Mediated Killing of Ampicillin- and Vancomycin- Resistant Enterococcus faecium. Antimicrob. Agents Chemother. 2012, 56(2):838.
18. Torabinejad M.Shabahand S .Aprecio PM Kettering JD. The Antimicrobial Effect of MTAD: An in vitroInvestigation. J Endod 2003: 29:400-403.
19. Shabahang S, Manouchehr P Torabinejad M. In Vitro antimicrobial efficacy of MTAD and NaOCI. J Endod 2003;29 (7):450-2.
20. Valerie Laganas, Jeffrey Alder, and Jared A. Silverman. In Vitro Bactericidal Act-ivities of Daptomycin against Staphylo-coccus aureusand Enterococcus faecalis  Are Not Mediated by Inhibition of Lipoteichoic Acid Biosynthesis. Antimicrob agents Chemother.Aug 2003;47(8):2682-2684
21. Shahbang S TorabinejadM.Effect of MTAD on Enterococcus Faecalis Conta-minated root canals of exacted human teeth. J Endod 2003;29 (9) 576-579.
22. Kenneth H.Rand, Herbert Houck. Daptomycin synergy with rifampicin and ampicillin against vancomycin-resistant enterococci. J. Antimicrob. Chemother.(2004) 53 (3): 530-532.
23. Protenier I Waltimo T, Orstavik D, Haapasalo M. Killing of Enterococcus faecalis by MTAD, Chlorhexidine diglu-conate and a combination of chlorhexidine digluconate and cetrimide in the presence of absence of potential inhibitors. J Endod. 2006 Feb;32(2):138-141.
24. Kho P, Banumgartner J A .Comparison of Antimicrobial Efficacy of NaOCI/Biopure MTAD Versus NaOCI/EDTA against Enterococcus faecalis.JEndod 2006:32:652-55.
25. Dunavant TR, Regan JD. Comparative Evaluation of Endodontic Irrigants against Enterococcus faecalis J Endod 2006:32:527-531.
26. Franklin R. Tay, Noriko Hiraishi, George S, David H, Robert et al. Reduction in antimicrobial substantivity of MTAD after intial sodium hypochlorite irrigation. .J Endod 2006;32:10.
27. Clegg MS, Verucci FJ, Walker C, Belanger M, Britto LR. The effect of exposure to irrigant solutions on apical dentin biofilms in vitro. J Endod 2006;32:434-7.
28. Melissa L Ruff , Scott B, Britta S.Babel. In Vitro Antifungal Efficacy of Four Irrigants as a Final Rinse. J Endod 2006;32(4):331-333.
29. Davis J M Maki J, Bahcall J.K. An In vitro Comparision of the Antimicrobial Effects of Various Endodontic Medicaments on Enterococcus Faecalis. J Endod 2007; 33:567-569.
30. Newberry BM Shabahang S Johnson N Aprecio RM, Torabindejad M The Antimicrobial Effect of Biopure MTAD on Eight Strains of Enerococcus Faecalis: An In vitro Investigation.JEndod 2007;33: 1352-1354.
31. Baumgartner JC, Johal S, Marshall GJ.Comparison of the Antimicrobial Efficacy of 1.3% NaOCL/ BioPure MTAD to 5.25% NaOCL/15% EDTA for Root Canal Irrigation. J Endod 2007; 33(1) : 48-51.
32. Giardino L, Ambu E, Cassanelli C, Debbia  EA .Comparative Evaluation of Antimicrobial Efficacy of Sodium Hypochlorite,  MTAD, and Tetraclean Against Enterococcus faecalis Biofilm. J Endod 2007; 33(7) : 852-855.
33. Krause TA, Liewher FR, Hahn C. The Antimicrobial Effect of MTAD, Sodium Hypochlorite, Doxycycline, and Citric Acid on Enterococcus faecalis. J Endod 2007; 33: 28-30.
34. Mohammadi Z Shahriari S. “Residual Antibacterial activity of CHX and MTAD in human root dentin in Vitro. “ J of oral science 2008; 50:163-67.
35. Ahangari Z, Samiee M, Yolmeh MA, Eslami G “Antimicrobial Activity of three root canal irrigants on Entercoccu faecalis. An in Vitro Study Iran Endod J 2008;3(2);33-37.
36. Shahrokh Shabahang, Joseph Aslanyan, Mahmoud Torabinejad. The Substitution of Chlorhexidine for Doxycycline in MTAD: The Antibacterial Efficacy Against a Strain of Enterococcus faecalis. J Endod 2008;34(3):288-290.
37. Ashari MA, Fayaz F Ghadim NM, Marvasti A Mehrabi Y. Evaluation of the antimicrobial effects of MTAD, NaOCI Against selected endodontic pathogens. Iran Endod J 2009; 4(2)”63-68.
38. Singh S, Krishna S, Acharya SR, Rao PS, Ballal V .Comparison of antimicrobial efficacy of Biopure MTAD and 2.5% sodium hypochlorite irrigation in infected root canals following single visit endodontics – An in vivo study.Endodontology 2009; 21(1) : 27-33.
39. GiardinoL, Savoldi E, Ambu E, Rimondini R, Plaezona A, Debbia EA . Antimicrobial effect of MTAD, Tetraclean, Cloreximid, and sodium hypochlorite on three common endodontic pathogens. Indian J Dent Res.2009 ; 20(3):391.
40. Srikumar GPV, Varma KR, Shetty KHK, Vidya . Comparison of the antibacterial efficiency of MTAD, 2.5% sodium hypochlorite and 2% Chlorhexidine against Enterococcus faecalis-An Ex vivo study.Endodontology 2009;21(1):41-47.
41. Malkhassian G, Manzur AJ, Legner M, Fillery ED, Manek S, Basrani BR, Friedman S . Antibacterial efficacy of MTAD final rinse and two percent chlorhexdine gel medication in teeth with apical periodontitis: a randomized double – blinded clinical trial.  J Endod. 2009; 35(11):1483-90.
42. Ardizzonil A, Blasi 1 E, Rimoldi 1 C, Giardino L, Ambu E, Righi 1 R, NegliaR .An in vitro and ex vivo study on two antibiotic-based endodontic irrigants: a challenge to sodium hypochlorite. New Microbiologica, 32,57-66,2009.
43. Prabakar J, Senthilkumar M, Priya MS, Mahalakshmi K, Shegal PK, Sukumaran VG “ Evaluation of Antimicrobial efficacy of herbal alternatives (Triphala and green tea polyphenols) MTAD, and 5 % sodium hypocolorite against Enterococcus faecalis biofilms formed on tooth substrate: a in vitro study” J Endod 2010; 36(1):83-6.
44. Arslan S, Ozbilge H, kaya EG, Er O “ In vitro antimicrobial activity of propolis Biopure MTAD, sodium hypochlorite, and chlorhexidine on Enterococcus faecalis and Candida albicans.” Saudi Med J. 2011 May; 32 (5): 479-83.
45. HemadriM , Sophia Thakur, GirijaSajjan. Nisin Vs Calcium Hydroxide – Antimicrobial Efficacy OnEnterococcus Feacalis – An In-vitro Study. IJCD.2011 June;2(3)
46. Blerim Kamberi, Donika Bajrami,  Miran-da Stavileci, Shuhreta Omeragiq,  Fatmir Dragidella, Ferit Koçani. The Antibacterial Efficacy of Biopure MTAD in Root Canal Contaminated with Enterococcus faecalis ISRN Dentistry. 2012.
47. Zhongchun Tong equal contributor,Lijia Huang equal contributor,Junqi Ling mail,Xueli Mao,Yang Ning,Dongmei Deng .Effects of Intracanal Irrigant MTAD Combined with Nisin at Sub-Minimum Inhibitory Concentration Levels on Enterococcus faecalisGrowth and the Expression of Pathogenic Genes. PLOS ONE. 2014 March;9:3.
48. Sundquvist G Figdor D “Life as an endodontic pathogen-Ecological difference between the untreated and root-filled root canals. “ Endod Topics 2003;6:3-28.
49. Spratt DA, Pratten J, Wilson M, Gulabivala K “ An in vitro evaluation of the antimicrobial efficacy of irrigants on biofilms of root canal isolates.” IntEndod J 2001;34;300-307.
50. Protenier I, Uomos MT, Waltimo, Haapasalo M “Enerococcus faecalis – The root canal survivor and Star in post treatment diseases” Endod Topic 2003:6:135-159.
51. Evans M Davies JK Sundqivst G, Figdo D : Mechanisms involved in the resistance of Enterococcus Faecalis to calcium hydroxide, IntEndod J 2002;35:221-8.
52. Stuart CH Schewartz SA, Beeso TJ. OwatzCB .Enterococcus faecalis: Its Role in Root Canal Treatment Failure and current concepts in Retreatment .J Endod 2006; 32: 93-98.
53. Luis Chavez De Paz. Gram – positive organisms in endodnticinfextions. Endodntic topics 2004,9:79-96.
54. Menezes MM, Valera MC, Jorge AO, Koga – Ito CY, Camargo CH, Mancini MN In vitro evaluation of the effectiveness of irrigants and intracanal medicaments on microorganisms within root canals. IntEndod J. 2004;37:311-9.
55. Siqueira JF, Rocas IN, Paiva SSM, Guimaraes-Pinto T Magalhaes KM, and Lima KC. Bacteriologic investigation of the effects of Sodium Hypocholrite and Chlorhexidine during the endodontic treatment of teeth with apical periodonitits. Oral Surg Oral Med Oral Pathol Oral RadiolEndod 2007:104:122-30.
56. Zehender M. Root canal irrigants, JEndod 2006; 32: 389-90.
57. HulsmannM , Hahn W. Complications during root canal irrigation- literature review and case reports. IntEndod J. 2000; 33(3): 186-93.
58. MohammadiZ .An update on the antibiotic-based root canal irrigation solutions. “Iran Endod JI 2008; 3:1-7.
59. Mohammadi Z Z. Systemic prophylactic and local applications of antimicrobials in endodontics update review.Int Dent J 2009: 59: 175-186.
60. Violich DR, Chandler NP . The Smear Layer in endodontics – a review .IntEndod J 2010;43:2-15.
61. Serota JS. MTAD-Tetracycline, Citric acid and detergent.Endod Solutions 2005; 2(3):1.
62. Zhongchun Tong, Lin Zhou, Rongkuang, Haipeng LV, Tiejun Qu. In VitroEvaluation of MTAD and Nisin in Combination against Common Pathogens Associated with Root Canal Infection. J Endod 2012; 38(4):490-494.
63. Cameron JA. The effect of a fluorocarbon surfactant on the surface tension of the endodontic irrigant, sodium hypochlorite. Aust Dent J 1986;13:364-8
64. Ferraz CC, Gomes BP, Zaia AA, et al. In vitro assessment of the antimicrobial action and the mechanical ability of chlorhexidine gel as an endodontic irrigant. J Endod 2001;27:452–5. 38. Gottardi W. Iodine and iodine compounds. In: Block SS, editor. Disinfection, sterilization, and preservation. 4th edition. Philadelphia: Lea & Febiger; 1991. p. 152–66.
65. Putt MS, Proskin HM. Custom Tray Application of Peroxide Gel as an Adjunct to Scaling and Root Planing in the Treatment of Periodontitis: A Randomized, Controlled Three-Month Clinical Trial. J. Clin Dent. 2012; 23:48-56.

S Sree Soumya

Dept of Conservative Dentistry and Endodontics,

Panineeya Institute of Dental Sciences and Hospital