Basic research—technology| Volume 33, ISSUE 1, P28-30, January 2007

The Antimicrobial Effect of MTAD, Sodium Hypochlorite, Doxycycline, and Citric Acid on Enterococcus faecalis

Published:October 30, 2006DOI:


      This study compared the antimicrobial effect of MTAD, two of its components, doxycycline and citric acid, and sodium hypochlorite (NaOCl) in two in vitro models on Enterococcus faecalis. In the bovine tooth model, the lumens of 30 bovine dentin discs were infected with E. faecalis for 2 weeks before treating with either one of the experimental irrigants or saline. Bacteria in the shavings were collected with two sizes of burs and enumerated after overnight culturing. Zones of inhibition were recorded in the agar diffusion model for each irrigant. In the tooth model, NaOCl and doxycycline were more effective than control in killing E. faecalis at the shallow bur depth, but at the deeper bur depth only NaOCl was superior. In the agar diffusion model, NaOCl produced less inhibition than MTAD or doxycycline.

      Key Words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Journal of Endodontics
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Ingle J.I.
        Root canal obturation.
        J Am Dent Assoc. 1956; 53: 47-55
        • Kakehashi S.
        • Stanley H.R.
        • Fitzgerald R.J.
        The effects of surgical exposures of dental pulps in germ-free and conventional laboratory rats.
        Oral Surg Oral Med Oral Pathol. 1965; 20: 340-349
        • Sundqvist G.
        • Figdor D.
        • Persson S.
        • Sjögren U.
        Microbiologic analysis of teeth with failed endodontic treatment and the outcome of conservative re-treatment.
        Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1998; 85: 86-93
        • Ringel A.M.
        • Patterson S.S.
        • Newton C.W.
        • Miller C.H.
        • Mulhern J.M.
        In vivo evaluation of chlorhexidine gluconate solution and sodium hypochlorite solution as root canal irrigants.
        J Endod. 1982; 8: 200-204
        • Hales J.J.
        • Jackson C.R.
        • Everett A.P.
        • Moore S.H.
        Treatment protocol for the management of a sodium hypochlorite accident during endodontic therapy.
        Gen Dent. 2001; 49: 278-281
        • Pashley E.L.
        • Birdsong N.L.
        • Bowman K.
        • Pashley D.H.
        Cytotoxic effects of NaOCl on vital tissue.
        J Endod. 1985; 11: 525-528
        • Neaverth E.J.
        • Swindle R.
        A serious complication following the inadvertent injection of sodium hypochlorite outside the root canal system.
        Compendium. 1990; 11 (476, 478–81.): 474
        • Shabahang S.
        • Torabinejad M.
        Effect of MTAD on Enterococcus faecalis-contaminated root canals of extracted human teeth.
        J Endod. 2003; 29: 576-579
        • Torabinejad M.
        • Khademi A.A.
        • Babagoli J.
        • et al.
        A new solution for the removal of the smear layer.
        J Endod. 2003; 29: 170-175
        • Torabinejad M.
        • Shabahang S.
        • Aprecio R.M.
        • Kettering J.D.
        The antimicrobial effect of MTAD: an in vitro investigation.
        J Endod. 2003; 29: 400-403
        • Smith J.J.
        • Wayman B.E.
        An evaluation of the antimicrobial effectiveness of citric acid as a root canal irrigant.
        J Endod. 1986; 12: 54-58
        • Demirel K.
        • Baer P.N.
        • McNamara T.F.
        Topical application of doxycycline on periodontally involved root surfaces in vitro: comparative analysis of substantivity on cementum and dentin.
        J Periodontol. 1991; 62: 312-316
        • Haapasalo M.
        • Orstavik D.
        In vitro infection and disinfection of dentinal tubules.
        J Dent Res. 1987; 66: 1375-1379
        • Fouad A.F.
        • Barry J.
        The effect of antibiotics and endodontic antimicrobials on the polymerase chain reaction.
        J Endod. 2005; 31: 510-513
        • Ciarlone A.E.
        • Johnson R.D.
        • Tomaselli Jr, D.L.
        • Sue Seale N.
        • Pashley D.H.
        The quantitative binding of tetracycline to dentin.
        J Endod. 1988; 14: 494-496
        • Hannig M.
        Effect of Carisolv solution on sound, demineralized and denatured dentin: an ultrastructural investigation.
        Clin Oral Investig. 1999; 3: 155-159
        • Tay F.R.
        • Pashley D.H.
        • Loushine R.J.
        • et al.
        Ultrastructure of smear layer-covered intraradicular dentin after irrigation with BioPure MTAD.
        J Endod. 2006; 32: 218-221
        • Portenier I.
        • Waltimo T.
        • Orstavik D.
        • Haapasalo M.
        The susceptibility of starved, stationary phase, and growing cells of Enterococcus faecalis to endodontic medicaments.
        J Endod. 2005; 31: 380-386
        • Clewell D.B.
        • Weaver K.E.
        Sex pheromones and plasmid transfer in Enterococcus faecalis.
        Plasmid. 1989; 21: 175-184
        • Kayaoglu G.
        • Orstavik D.
        Virulence factors of Enterococcus faecalis: relationship to endodontic disease.
        Crit Rev Oral Biol Med. 2004; 15: 308-320
        • Vanuspong W.
        • Eisenburger M.
        • Addy M.
        Cervical tooth wear and sensitivity: erosion, softening and rehardening of dentine; effects of pH, time and ultrasonication.
        J Clin Periodontol. 2002; 29: 351-357
        • Abou-Rass M.
        • Patonai Jr, F.J.
        The effects of decreasing surface tension on the flow of irrigating solutions in narrow root canals.
        Oral Surg Oral Med Oral Pathol. 1982; 53: 524-526
        • Baker N.A.
        • Eleazer P.D.
        • Averbach R.E.
        • Seltzer S.
        Scanning electron microscopic study of the efficacy of various irrigating solutions.
        J Endod. 1975; 1: 127-135
        • Buck R.A.
        • Eleazer P.D.
        • Staat R.H.
        • Scheetz J.P.
        Effectiveness of three endodontic irrigants at various tubular depths in human dentin.
        J Endod. 2001; 27: 206-208
        • Gutierrez J.H.
        • Jofre A.
        • Villena F.
        Scanning electron microscope study on the action of endodontic irrigants on bacteria invading the dentinal tubules.
        Oral Surg Oral Med Oral Pathol. 1990; 69: 491-501