Micro-computed tomography evaluation of the preparation of long oval root canals in mandibular molars with the self-adjusting file

INTRODUCTION: The aim of this study was to assess the shaping potential of a novel nickeltitanium instrument, the self-adjusting file (SAF), in long oval root canals in distal roots in mandibular molars. METHODS: Twenty mandibular molars with long oval distal root canals were selected and scanned preoperatively and postoperatively by using micro-computed tomography at an original resolution of 20 �m. Canals were shaped with the SAF, three-dimensionally reconstructed, and evaluated for volume, surface area, canal transportation, and prepared surface. Data were statistically contrasted by using paired t tests and regression analysis. RESULTS: Preoperatively, canal volume was 7.73 ± 2.13 mm(3), and canal area was 42.83 ± 8.14 mm(2). Volumes and surface areas increased significantly (P < .001) by 4.84 ± 1.73 mm(3) and 3.34 ± 1.73 mm(2), respectively, and no gross preparation errors were detected. Unprepared canal surface varied between individual canals, and mean unprepared surface was 23.5% ± 8.9%. Prepared areas were significantly larger compared with rotary canal preparation done in a previous study. Canal transportation scores were higher in the coronal root canal third (106 ± 50 �m) compared with the apical third (81 ± 49 �m). CONCLUSIONS: In vitro, preparation of long oval-shaped root canals in mandibular molars with the SAF was effective and safe. Moreover, shapes generated with the SAF were more complete compared with rotary canal preparation. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved. DOI: https://doi.org/10.1016/j.joen.2010.12.011 Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-58506 Accepted Version Originally published at: Paqué, F; Peters, O A (2011). Micro-computed tomography evaluation of the preparation of long oval root canals in mandibular molars with the self-adjusting file. Journal of Endodontics, 37(4):517-521. DOI: https://doi.org/10.1016/j.joen.2010.12.011 A micro-computed tomography evaluation of the preparation of long oval root canals in mandibular molars with the self-adjusting file (SAF) Frank Paqué (Dr med dent), Ove A. Peters (DMD MS PhD) 1 University of Zurich Dental School, Division of Endodontology, Zurich, Switzerland 2 University of The Pacific, Arthur A. Dugoni School of Dentistry, Department of Endodontics, San Francisco, USA Correspondence: Dr. Frank Paqué University of Zurich Dental School Plattenstr. 11 CH-8028 Zurich Phone: +41 44 6343468 Fax: + 41 44 634 43 08 e-mail: [email protected]