Comparison of Seal After Obturation Techniques Using a Polydimethylsiloxane-Based Root Canal Sealer Martha G. Brackett, DDS,* Rebecca Martin, BS, † Jeremy Sword, BS, ‡ Cindy Oxford, BS,* Frederick A. Rueggeberg, DDS, MS,* Franklin R. Tay, BDSc (Hons), PhD, ‡ and David H. Pashley, DMD, PhD ‡ Abstract A polydimethylsiloxane-based sealer (GuttaFlow) was used for filling single-rooted teeth with four obturation techniques. Prefitted gutta-percha master-cones were employed in groups 1 to 3 with backfilling of the sealer. Apical third of the roots were first filled with GuttaFlow, and sealer-coated master cones were seated with up-and- down motion (group 1) or rotated to place (group 2). Master-cones were used as carriers for introducing Gut- taFlow into the canals (group 3). Canals were filled with GuttaFlow without master-cones (group 4). Canals were filled with AH Plus/gutta-percha using warm vertical com- paction (control group 5). All obturated canals were tested for leakage after 1, 6, and 12 weeks using the fluid filtration technique. All groups exhibited equivalent seal regardless of time except for more extensive leakage in group 3. The use of GuttaFlow with a single gutta-percha master cone creates an apical seal that is equivalent to that produced with gutta-percha/AH Plus sealer using warm vertical compaction. (J Endod 2006;32:1188 –1190) Key Words AH Plus sealer, fluid filtration, GuttaFlow, leakage M any different endodontic obturation techniques, materials, and sealers are avail- able (1–10). The ideal materials should be biocompatible with periapical tissues, easy to use, opaque to X-rays, expand slightly on setting, easily removed, and provide an excellent seal over time. Recently, a polydimethylsiloxane-based root canal sealer has been introduced. The initial version was called RoekoSeal (Colténe/Whaledent, Altstätten, Switzerland). Several studies have reported excellent biocompatibility and apical sealing using this material (11–14). RoekoSeal has been improved by adding nanosilver particles and powdered gutta-percha to create a new material called GuttaFlow (Coltène/Whaledent). An initial report on film thickness and flow properties of this gutta-percha containing sealer has been positive (15). The purpose of this study was to compare the sealing quality of GuttaFlow that was employed with different gutta-percha single-cone techniques, with that of warm vertically compacted gutta-percha/AH Plus sealer using the fluid filtration technique (16 –18). The null hypothesis was that there are no differences in the ability of GuttaFlow to seal root canals compared to a conventional warm vertical compaction technique. It was further hypothesized that the sealing qualities of GuttaFlow using an injection technique versus that when using a master-cone to carry GuttaFlow to the apex are not different, and that these sealing qualities would not be compromised over 12 weeks of water storage. Materials and Methods Fifty-four single-rooted, extracted anterior human teeth were used under a pro- tocol approved by the IRB of the Medical College of Georgia. The crowns were sectioned so that all roots were approximately 17 mm long. Cleaning and shaping and canal obturation were performed under an operating microscope (OPMI Pico, Carl Zeiss Surgical, Inc., Thornwood, NY), with radiographic documentation of the preoperative specimens, working lengths, cone-fit, and postoperative condition of the root fillings. Canal patency was achieved with an ISO #15 file (Flex-O-File, DentsplyTulsa, Tulsa, OK). The working length was established 0.5 mm short of the apex. Instrumentation was performed with a crown-down technique, using Gates Glidden drills and 0.06 taper nickel-titanium rotary instruments (Sequence, Brasseler, Savannah, GA) to ISO #40. The canals were alternately irrigated with 10 ml of 6.15% sodium hypochlorite (NaOCl) (Clorox, Oakland, CA) and 10 ml of 17% ethylenediaminetetraacetic acid (EDTA) (Pulpdent Corporation, Watertown, MA) in between instrumentation, with the latter employed for 1 min as the final rinse. The canals were dried with multiple paper points and then randomly divided into five groups (n = 10). Two additional roots were used as the positive control and another two as the negative control. Filling Techniques Group 1: GuttaFlow Obturation Using Master-Cone With Up-and-Down Movement A nonstandardized 0.06 taper gutta-percha master-cone (Hygienic Inc., Cuyahoga Falls, OH) was trimmed with a gutta gauge (DentsplyTulsa) to ISO size #40 and prefitted with tug-back. A capsule of GuttaFlow was triturated for 20 sec in an amalgamator. A small quantity of GuttaFlow was placed on a mixing pad for coating master-cones. Using a special tip and syringe provided by the manufacturer, GuttaFlow was injected to fill the apical-third From the *Department of Oral Rehabilitation, † Dental Student, ‡ Department of Oral Biology & Maxillofacial Pathol- ogy, School of Dentistry, Medical College of Georgia, Augusta, Georgia. Address requests for reprints to Dr. David H. Pashley, Department of Oral Biology & Maxillofacial Pathology, School of Dentistry, Medical College of Georgia, 1120 15th Street, CL-2112, Augusta, GA 30912-1129. E-mail address: dpashley@ mail.mcg.edu. 0099-2399/$0 - see front matter Copyright © 2006 by the American Association of Endodontists. doi:10.1016/j.joen.2006.07.009 Basic Research—Technology 1188 Brackett et al. JOE — Volume 32, Number 12, December 2006