Basic Research| Volume 38, ISSUE 5, P688-691, May 2012

In Vitro Comparison of Passive and Continuous Ultrasonic Irrigation in Simulated Lateral Canals of Extracted Teeth

Published:January 30, 2012DOI:



      Complete endodontic system disinfection requires the removal of vital and necrotic pulp tissue, microorganisms, and toxins. The purpose of this study was to compare the effects of 2 ultrasonic irrigation techniques on the penetration of sodium hypochlorite into the main canal and simulated lateral canals of extracted teeth.


      Two simulated lateral canals each were created 2, 4, and 6 mm from the working length in 60 single-rooted teeth (6 canals/tooth, n = 360). To resemble the clinical situation, a closed system was created in each tooth. The teeth were randomly assigned to 3 experimental irrigation groups: group 1 (n = 20), positive pressure irrigation (PPI); group 2 (n = 20), passive ultrasonic irrigation (PUI); and group 3 (n = 20), continuous ultrasonic irrigation (CUI). Samples were evaluated by direct observation of still images recorded under a dental operating microscope. To examine irrigating solution penetration, 20% Chinese ink (Sanford Rotring GmbH, Hamburg, Germany) was added to a 5% sodium hypochlorite solution and delivered into the root canals.


      The results showed a significantly higher (P < .05) penetration of irrigant into the lateral canals in the CUI group. PUI and CUI did not differ significantly in solution penetration into the apical thirds of the main canals. The PPI group showed a significantly lower penetration of sodium hypochlorite into the main and lateral canals compared with the CUI and PUI groups.


      CUI as a final rinse significantly increased the penetration of irrigating solution into simulated lateral canals.

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        • Siqueira Jr., J.F.
        • Rôças I.N.
        Clinical implications and microbiology of bacterial persistence after treatment procedures.
        J Endod. 2008; 34: 1291-1301
        • Gutarts R.
        • Nusstein J.
        • Reader A.
        • Beck M.
        In vivo debridement efficacy of ultrasonic irrigation following hand-rotary instrumentation in human mandibular molars.
        J Endod. 2005; 31: 166-170
        • Gu L.S.
        • Kim J.R.
        • Ling J.
        • et al.
        Review of contemporary irrigant agitation techniques and devices.
        J Endod. 2009; 35: 791-804
        • de Gregorio C.
        • Estevez R.
        • Cisneros R.
        • Paranjpe A.
        • Cohenca N.
        Efficacy of different irrigation and activation systems on the penetration of sodium hypochlorite into simulated lateral canals and up to working length: an in vitro study.
        J Endod. 2010; 36: 1216-1221
        • Burleson A.
        • Nusstein J.
        • Reader A.
        • Beck M.
        The in vivo evaluation of Hand/Rotatory/Ultrasoud instrumentation in necrotic, human mandibular molars.
        J Endod. 2007; 33: 782-787
        • Siqueira Jr., J.F.
        • Lima K.C.
        • Magalhaes F.A.
        • Lopes H.P.
        • de Uzeda M.
        Mechanical reduction of the bacterial population in the root canal by three instrumentation techniques.
        J Endod. 1999; 25: 332-335
        • Peters O.A.
        Current challenges and concepts in the preparation of root canal systems: a review.
        J Endod. 2004; 30: 559-567
        • Nielsen B.A.
        • Baumgartner J.C.
        Comparison of the endovac system to needle irrigation of root canals.
        J Endod. 2007; 33: 611-615
        • Gao Y.
        • Haapasalo M.
        • Shen Y.
        • et al.
        Development and validation of a three-dimensional computational fluid dynamics model of root canal irrigation.
        J Endod. 2009; 35: 1282-1287
        • Ahmad M.
        • Pitt Ford T.R.
        • Crum L.A.
        • et al.
        Ultrasonic debridement of root canals: acoustic cavitation and its relevance.
        J Endod. 1988; 14: 486-493
        • Carver K.
        • Nusstein J.
        • Reader A.
        • Beck M.
        In vivo antibacterial efficacy of ultrasound after hand and rotary instrumentation in human mandibular molars.
        J Endod. 2007; 33: 1038-1043
        • van der Sluis L.W.
        • Versluis M.
        • Wu M.K.
        • et al.
        Passive ultrasonic irrigation of the root canal: a review of the literature.
        Int Endod J. 2007; 40: 415-426
        • Stojicic S.
        • Zivkovic S.
        • Qian W.
        • Zhang H.
        • Haapasalo M.
        Tissue dissolution by sodium hypochlorite: effect of concentration, temperature, agitation, and surfactant.
        J Endod. 2010; 36: 1558-1562
        • Zehnder M.
        Root canal irrigants.
        J Endod. 2006; 32: 389-398
        • Tay F.R.
        • Gu L.S.
        • Schoeffel G.J.
        • et al.
        Effect of vapor lock on root canal debridement by using a side-vented needle for positive-pressure irrigant delivery.
        J Endod. 2010; 36: 745-750
        • Robertson D.C.
        • Leeb I.J.
        The evaluation of a transparent tooth model system for the evaluation of endodontically filled teeth.
        J Endod. 1982; 8: 317-321
        • Ricucci D.
        • Siqueira Jr., J.F.
        Fate of the tissue in lateral canals and apical ramifications in response to pathologic conditions and treatment procedures.
        J Endod. 2010; 36: 1-15
        • Weine F.
        The enigma of the lateral canal.
        Dent Clin North Am. 1984; 28: 833-852
        • Xu G.
        • Zhang Z.
        Filling of the lateral canal.
        Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1984; 58: 221-224
        • Migun N.P.
        • Shnip A.I.
        Model of film flow in a dead-end conic capillary.
        J Eng Phys Thermophys. 2002; 75: 1422-1428
        • Usman N.
        • Baumgartner J.C.
        • Marshall J.G.
        Influence of instrument size on root canal debridement.
        J Endod. 2004; 30: 110-112
        • Khademi A.
        • Yazdizadeh M.
        • Feizianfard M.
        Determination of the minimum instrumentation size for penetration of irrigants to the apical third of root canal systems.
        J Endod. 2006; 32: 417-420
        • Grandini S.
        • Balleri P.
        • Ferrari M.
        Evaluation of Glyde File Prep in combination with sodium hypochlorite as a root canal irrigant.
        J Endod. 2002; 28: 300-303
        • Usman N.
        • Baumgartner J.C.
        • Marshall J.G.
        Influence of instrument size on root canal debridement.
        J Endod. 2004; 30: 110-112
        • O’Connell M.S.
        • Morgan L.A.
        • Beeler W.J.
        • Baumgartner J.C.
        A comparative study of smear layer removal using different salts of EDTA.
        J Endod. 2000; 26: 739-743
        • Van der Sluis L.
        • Wu M.
        • Wesselink P.
        The efficacy of ultrasonic irrigation to remove artificially placed dentine debris from human root canals prepared using instruments of varying taper.
        Int Endod J. 2005; 38: 764-768
        • Lee S.J.
        • Wu M.K.
        • Wesselink P.R.
        The effectiveness of syringe irrigation and ultra- sonics to remove debris from simulated irregularities within prepared root canal walls.
        Int Endod J. 2004; 37: 672-678
        • Al-Jadaa A.
        • Paqué F.
        • Attin T.
        • Zehnder M.
        Necrotic pulp tissue dissolution by passive ultrasonic irrigation in simulated accessory canals: impact of canal location and angulation.
        Int Endod J. 2009; 42: 59-65
        • Al-Jadaa A.
        • Paqué F.
        • Attin T.
        • Zehnder M.
        Acoustic hypochlorite activation in simulated curved canals.
        J Endod. 2009; 35: 1408-1411