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Chemomechanical Reduction of the Bacterial Population in the Root Canal after Instrumentation and Irrigation with 1%, 2.5%, and 5.25% Sodium Hypochlorite

  • José F. Siqueira Jr
    Correspondence
    Address requests for reprints to Dr. José F. Siqueira, Jr., R. Herotides de Oliveira 61/601, Icaraí, Niterói, RJ, Brazil 24230-230
    Affiliations
    Dr. Siqueira is chairman and professor, and Drs. Rôças and Favieri are professors of Endodontics, Department of Dentistry, Estacio de Sá University, Rio de Janeiro, Brazil. Dr. Lima is professor of Preventive Dentistry, Federal University of Rio Grande do Norte, Natal, Brazil.
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  • Isabela N. Rôças
    Affiliations
    Dr. Siqueira is chairman and professor, and Drs. Rôças and Favieri are professors of Endodontics, Department of Dentistry, Estacio de Sá University, Rio de Janeiro, Brazil. Dr. Lima is professor of Preventive Dentistry, Federal University of Rio Grande do Norte, Natal, Brazil.
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  • Amauri Favieri
    Affiliations
    Dr. Siqueira is chairman and professor, and Drs. Rôças and Favieri are professors of Endodontics, Department of Dentistry, Estacio de Sá University, Rio de Janeiro, Brazil. Dr. Lima is professor of Preventive Dentistry, Federal University of Rio Grande do Norte, Natal, Brazil.
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  • Kenio C. Lima
    Affiliations
    Dr. Siqueira is chairman and professor, and Drs. Rôças and Favieri are professors of Endodontics, Department of Dentistry, Estacio de Sá University, Rio de Janeiro, Brazil. Dr. Lima is professor of Preventive Dentistry, Federal University of Rio Grande do Norte, Natal, Brazil.
    Search for articles by this author
      Given the importance of bacteria in the development of periradicular lesions, the eradication of the root canal infection is paramount in endodontic treatment. This study evaluated the in vitro intracanal bacterial reduction produced by instrumentation and irrigation with 1%, 2.5%, and 5.25% sodium hypochlorite (NaOCl) or saline solution. Root canals inoculated with Enterococcus faecalis were instrumented and irrigated with the solutions tested. Canals were sampled before and after preparation. After serial dilution, samples were plated onto Mitis salivarius agar, and the colony-forming units grown were counted. Inhibitory effects of the three NaOCl solutions on E. faecalis were also evaluated by means of the agar diffusion test. All test solutions significantly reduced the number of bacterial cells in the root canal (p < 0.05). There was no significant difference between the three NaOCl solutions tested (p > 0.05). Nonetheless, all NaOCl solutions were significantly more effective than saline solution in reducing the number of bacterial cells within the root canal (p < 0.05). The three NaOCl concentrations showed large zones of inhibition against E. faecalis. The results of this study suggest that regular exchange and the use of large amounts of irrigant should maintain the antibacterial effectiveness of the NaOCl solution, compensating for the effects of concentration.
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      References

        • Kakehashi S
        • Stanley HR
        • Fitzgerald RJ
        The effects of surgical exposures of dental pulps in germ-free and conventional laboratory rats.
        Oral Surg. 1965; 20: 340-349
        • Möller AJR
        • Fabricius L
        • Dahlén G
        • Öhman AE
        • Heyden G
        Influence on periapical tissues of indigenous oral bacteria and necrotic pulp tissue in monkeys.
        Scand J Dent Res. 1981; 89: 475-484
        • Sundqvist G
        Bacteriological studies of necrotic dental pulps [Dissertation]. University of Umea, Umea, Sweden1976
        • Sundqvist G
        • Figdor D
        Endodontic treatment of apical periodontitis.
        in: Orstavik D Pitt Ford T Essential endodontology. Blackwell Science Ltd., Oxford1998: 242-277
        • 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. 1998; 85: 86-93
        • Siqueira Jr, JF
        • Lima KC
        • Magalhães FAC
        • Lopes HP
        • Uzeda M
        Mechanical reduction of the bacterial cell number inside the root canal by three instrumentation techniques.
        J Endodon. 1999; 25: 332-335
        • Siqueira Jr, JF
        • Machado AG
        • Silveira RM
        • Lopes HP
        • Uzeda M
        Evaluation of the effectiveness of sodium hypochlorite used with three irrigation methods in the elimination of Enterococcus faecalis from the root canal.
        Int Endod J. 1997; 30: 279-282
        • Byström A
        • Sundqvist G
        Bacteriologic evaluation of the effect of 0.5 percent sodium hypochlorite in endodontic therapy.
        Oral Surg. 1983; 55: 307-312
        • Bloomfield SF
        • Miles GA
        The antibacterial properties of sodium dichloroisocyanurate and sodium hypochlorite formulations.
        J Appl Bacteriol. 1979; 46: 65-73
        • Siqueira Jr, JF
        • Batista MMD
        • Fraga RC
        • Uzeda M
        Antibacterial effects of endodontic irrigants on black-pigmented gram-negative anaerobes and facultative bacteria.
        J Endodon. 1998; 24: 414-416
        • Rutala WA
        • Weber DJ
        Uses of inorganic hypochlorite (bleach) in health-care facilities.
        Clin Microbiol Rev. 1997; 10: 597-610
        • Spangberg L
        • Engström B
        • Langeland K
        Biologic effects of dental materials. III. Toxicity and antimicrobial effect of endodontic antiseptics in vitro.
        Oral Surg. 1973; 36: 856-871
        • Thé SD
        • Maltha JC
        • Plasschaert AJM
        Reactions of guinea pig subcutaneous connective tissue following exposure to sodium hypochlorite.
        Oral Surg. 1980; 49: 460-466
        • Yesilsoy C
        • Whitaker E
        • Cleveland D
        • Phillips E
        • Trope M
        Antimicrobial and toxic effects of established and potential root canal irrigants.
        J Endodon. 1995; 21: 513-515
        • Byström A
        • Sundqvist G
        The antibacterial action of sodium hypochlorite and EDTA in 60 cases of endodontic therapy.
        Int Endod J. 1985; 18: 35-40
        • Cvek M
        • Nord C-E
        • Hollender L
        Antimicrobial effect of root canal débridement in teeth with immature root. A clinical and microbiologic study.
        Odontol Revy. 1976; 27: 1-10
        • Siqueira Jr, JF
        Tratamento das infecções endodônticas. Rio de Janeiro: MEDSI, 1997
        • Molander A
        • Reit C
        • Dahlén G
        • Kvist T
        Microbiological status of root-filled teeth with apical periodontitis.
        Int Endod J. 1998; 31: 1-7
        • Möller AJR
        Microbial examination of root canals and periapical tissues of human teeth.
        Odontol Tidskrift. 1966; 74: 1-380
        • Baumgartner JC
        • Cuenin PR
        Efficacy of several concentrations of sodium hypochlorite for root canal irrigation.
        J Endodon. 1992; 18: 605-612