Micro-computed tomography evaluation of the preparation of mesiobuccal root canals in maxillary first molars with Hyflex CM, Twisted Files, and K3 instruments.

INTRODUCTION The aim of this study was to describe the canal shaping properties of Hyflex CM, Twisted Files (TF), and K3 rotary nickel-titanium files by using micro-computed tomography in maxillary first molars. METHODS A total of 36 mesiobuccal root canals of maxillary first molars were prepared with Hyflex CM, TF, or K3 system. Micro-computed tomography was used to scan the specimens before and after instrumentation. The volume of untreated canal, volume of dentin removed after preparation, amount of uninstrumented area, and the transportation for the coronal, middle, and apical thirds of canals were measured. RESULTS Instrumentation of canals increased their volume and surface area. TF group showed the greatest amount of volumetric dentin removal (P < .05), whereas no significant difference was found in Hyflex CM and K3 groups. There were no significant differences among instrument types concerning uninstrumented area. The TF system produced significantly less transportation than the K3 system in the apical third of canals. No significant difference was found between TF and Hyflex CM instruments relating to apical transportation. CONCLUSIONS In vitro, Hyflex and TF instruments shaped curved root canals in maxillary first molar without significant shaping errors.

[1]  Richard Gergi,et al.  Comparison of canal transportation and centering ability of twisted files, Pathfile-ProTaper system, and stainless steel hand K-files by using computed tomography. , 2010, Journal of endodontics.

[2]  M. Hülsmann,et al.  Comparative study of root-canal preparation using Lightspeed and Quantec SC rotary NiTi instruments. , 2003, International endodontic journal.

[3]  Ikuya Watanabe,et al.  Cyclic fatigue analysis of a new generation of nickel titanium rotary instruments. , 2009, Journal of endodontics.

[4]  Ya Shen,et al.  Metallurgical characterization of controlled memory wire nickel-titanium rotary instruments. , 2011, Journal of endodontics.

[5]  Sangeeta Talwar,et al.  An in vitro cyclic fatigue analysis of different endodontic nickel-titanium rotary instruments. , 2012, Journal of endodontics.

[6]  J. Gutmann,et al.  Alteration in the inherent metallic and surface properties of nickel-titanium root canal instruments to enhance performance, durability and safety: a focused review. , 2012, International endodontic journal.

[7]  Gianluca Gambarini,et al.  Fatigue resistance of engine-driven rotary nickel-titanium instruments produced by new manufacturing methods. , 2008, Journal of endodontics.

[8]  Ya Shen,et al.  Irrigation in endodontics. , 2010, Dental clinics of North America.

[9]  M-K Wu,et al.  The capability of two hand instrumentation techniques to remove the inner layer of dentine in oval canals. , 2003, International endodontic journal.

[10]  K. Gulabivala,et al.  The influence of preparation technique and sodium hypochlorite on removal of pulp and predentine from root canals of posterior teeth. , 2001, International endodontic journal.

[11]  Khalid H Alomairy.  Evaluating two techniques on removal of fractured rotary nickel-titanium endodontic instruments from root canals: an in vitro study. , 2009, Journal of endodontics.

[12]  Bock Hur,et al.  Dynamic torsional resistance of nickel-titanium rotary instruments. , 2010, Journal of endodontics.

[13]  Yuan Gao,et al.  Fatigue testing of controlled memory wire nickel-titanium rotary instruments. , 2011, Journal of endodontics.

[14]  Ove A Peters,et al.  Current challenges and concepts in the preparation of root canal systems: a review. , 2004, Journal of endodontics.

[15]  C. Elias,et al.  Influence of different manufacturing methods on the cyclic fatigue of rotary nickel-titanium endodontic instruments. , 2011, Journal of endodontics.

[16]  R M Love,et al.  A Micro CT study of the mesiobuccal root canal morphology of the maxillary first molar tooth. , 2011, International endodontic journal.

[17]  O A Peters,et al.  Root-canal preparation with FlexMaster: canal shapes analysed by micro-computed tomography. , 2003, International endodontic journal.

[18]  P. Rüegsegger,et al.  Three-dimensional Analysis of Root Canal Geometry by High-resolution Computed Tomography , 2000, Journal of dental research.

[19]  O. Peters,et al.  ProTaper rotary root canal preparation: assessment of torque and force in relation to canal anatomy. , 2003, International endodontic journal.

[20]  S A Thompson,et al.  Shaping ability of Quantec Series 2000 rotary nickel-titanium instruments in simulated root canals: Part 2. , 2002, International endodontic journal.

[21]  K. M. El Batouty,et al.  Comparison of canal transportation and changes in canal curvature of two nickel-titanium rotary instruments. , 2011, Journal of endodontics.

[22]  J. Simon,et al.  Healing of apical periodontitis after endodontic treatment with and without obturation in dogs. , 2006, Journal of endodontics.

[23]  G Gambarini,et al.  Mechanical properties of nickel-titanium rotary instruments produced with a new manufacturing technique. , 2011, International endodontic journal.

[24]  S. W. Schneider,et al.  A comparison of canal preparations in straight and curved root canals. , 1971, Oral surgery, oral medicine, and oral pathology.

[25]  S. A. Thompson.  An overview of nickel-titanium alloys used in dentistry. , 2000, International endodontic journal.

[26]  O A Peters,et al.  Changes in root canal geometry after preparation assessed by high-resolution computed tomography. , 1999, Journal of endodontics.

[27]  H Suda,et al.  Phase transformation behaviour and bending property of twisted nickel-titanium endodontic instruments. , 2011, International endodontic journal.

[28]  L Bergmans,et al.  Mechanical root canal preparation with NiTi rotary instruments: rationale, performance and safety. Status report for the American Journal of Dentistry. , 2001, American journal of dentistry.

[29]  An in vitro comparison of torsional stress and cyclic fatigue resistance of ProFile GT and ProFile GT Series X rotary nickel-titanium files. , 2009, Journal of endodontics.

[30]  O A Peters,et al.  Effects of four Ni-Ti preparation techniques on root canal geometry assessed by micro computed tomography. , 2001, International endodontic journal.

[31]  G. Yuan,et al.  Effects of two nickel-titanium instrument systems, Mtwo versus ProTaper universal, on root canal geometry assessed by micro-computed tomography. , 2011, Journal of endodontics.

[32]  K. Wilkinson,et al.  Effects of raw material and rotational speed on the cyclic fatigue of ProFile Vortex rotary instruments. , 2010, Journal of endodontics.

[33]  Sergio Kuttler,et al.  Comparison between a novel nickel-titanium alloy and 508 nitinol on the cyclic fatigue life of ProFile 25/.04 rotary instruments. , 2008, Journal of endodontics.

[34]  F. Paqué,et al.  Root canal preparation of maxillary molars with the self-adjusting file: a micro-computed tomography study. , 2011, Journal of endodontics.

[35]  O. Peters,et al.  ProTaper rotary root canal preparation: effects of canal anatomy on final shape analysed by micro CT. , 2003, International endodontic journal.