Short- and long-term sealing ability of Gutta-flow and AH-Plus using an ex vivo fluid transport model L. Vasiliadis, K. Kodonas, N. Economides, C. Gogos & C. Stavrianos Department of Endodontology, School of Dentistry, Aristotle University of Thessaloniki, Thessaloniki, Greece Abstract Vasiliadis L, Kodonas K, Economides N, Gogos C, Stavrianos C. Short- and long-term sealing ability of Gutta- flow and AH-Plus using an ex vivo fluid transport model. International Endodontic Journal, 43, 377–381, 2010. Aim To use the fluid transport model to evaluate the ex vivo short- and long-term microleakage along root canals filled with Gutta-flow or AH-Plus using the cold lateral compaction technique. Methodology A total of 38 single-rooted human teeth were used for the assessment of microleakage. The crowns of the teeth were sectioned below their cemento–enamel junctions to adjust the length of the roots to approximately 15 mm. The root canals were instrumented using the step-back technique and filled using cold lateral condensation. The sealer employed was either Gutta-flow (Group A) or AH-Plus (Group B). Microleakage along the root canals was evaluated using a fluid transport model after periods of 1 week and 3 months. Results The microleakage values (lLh )1 ) for group A were 0.36 ± 0.33 at 1 week and 0.41 ± 0.36 at 3 months. Group B showed mean microleakage values 0.2 ± 0.31 at 1 week and 0.28 ± 0.38 at 3 months. Statistical analysis indicated no significant differences (P > 0.05) between the two groups after either 1 week or 3 months. Conclusions There was no significant difference between AH-plus and Gutta-flow in terms of sealing ability. Keywords: AH-Plus, fluid transport model, Gutta- flow. Received 13 March 2009; accepted 7 December 2009 Introduction Epoxy resin sealers are popular because of their reduced solubility, their apical seal and their micro-retention to root dentine (Sousa-Neto et al. 2002, Tagger et al. 2002, Carvalho-Ju ´ nior et al. 2003). AH-Plus (Dentsply Maillefer, Ballaigues, Switzerland) is a silver-free epoxy- based sealer used in conjunction with gutta-percha in various root filling techniques. Gutta-flow (Coltene/ Whaledent, Altstatten, Switzerland) is an alternative root filling material recently introduced into the endodontic practice. It is a cold-flowable, self-curing material composed of gutta-percha powder, poly- dimethylsiloxane and silver particles. According to the manufacturer, Gutta-flow might be used with gutta- percha either in single-cone obturation or in the cold lateral compaction technique (Guttaflow instruction for use, Coltene/Whaledent Inc. 2008). Good sealing ability is a fundamental requirement of root filling materials (AliGhamdi & Wennberg 1994). Laboratory methods to assess leakage have included dyes, glucose, radioisotope tracers, fluid transport and bacteria (Pathomvanich & Edmunds 1996, Siqueira et al. 1999), and there is no consensus concerning the methods used (Wu & Wesselink 1993). The fluid transport model is based on the concept that fluid movement will be detected if the filled root canal system is not fluid-tight. This method has the advantages of quantifying microleakage and permitting repeated measurements on the same sample (Wu et al. 1994, Camps & Pashley 2003). Correspondence: K. Kodonas, Department of Endodontology, School of Dentistry, Aristotle University of Thessaloniki, GR–54124 Thessaloniki, Greece (Tel./fax: +30 2310 999 592; e-mail: kkodonas@dent.auth.gr). doi:10.1111/j.1365-2591.2010.01689.x ª 2010 International Endodontic Journal International Endodontic Journal, 43, 377–381, 2010 377