Shaping ability of progressive versus constant taper instruments in curved root canals of extracted teeth
- 23 July 2007
- journal article
- Published by Wiley in International Endodontic Journal
- Vol. 40 (9), 707-714
- https://doi.org/10.1111/j.1365-2591.2007.01296.x
Abstract
Aim To compare the shaping ability of progressive versus constant taper shaft instruments in curved root canals of extracted human teeth. Methodology A total of 40 root canals of mandibular molars with curvatures ranging between 20° and 40° were divided into two groups of 20 canals each and embedded in a muffle system. The root canals sectioned horizontally at three levels before preparation and then remounted into the mould. All root canals were prepared with ProTaper (progressive taper) or Hero Shaper (constant taper) instruments. Pre‐ and post‐instrumentation radiographs and cross‐sectional images were obtained. The parameters evaluated were: working safety (instrument failure, apical blockage and loss of working length) and shaping ability (straightening, cross‐sectional area, transportation and centring ability). The data were analysed statistically using Student’s t‐test. Results No instrument fractured during preparation. One Hero Shaper instrument permanently deformed. Both instrument systems maintained working length well. The canals prepared with Hero Shaper instruments were straightened to a lesser degree (P < 0.05). ProTaper instruments removed more dentine in the coronal and the middle sections of the canals. Canals prepared with Hero Shaper instruments had less transportation (P < 0.01) and better centring ability (P < 0.05) in the apical section. Conclusions Both instrument systems were safe to use and maintained working length well. The canals prepared with Hero Shaper had less transportation and were better centred in the apical region, possibly because their smaller taper reduced instrument stiffness.This publication has 23 references indexed in Scilit:
- Comparative study on the shaping ability and cleaning efficiency of rotary Mtwo instruments. Part 1. Shaping ability in simulated curved canalsInternational Endodontic Journal, 2006
- Comparative study of six rotary nickel-titanium systems and hand instrumentation for root canal preparationInternational Endodontic Journal, 2005
- Comparison of root canal preparation using RaCe and ProTaper rotary Ni‐Ti instrumentsInternational Endodontic Journal, 2004
- Comparative investigation of two rotary nickel–titanium instruments: ProTaper versus RaCe. Part 2. Cleaning effectiveness and shaping ability in severely curved root canals of extracted teethInternational Endodontic Journal, 2004
- Comparison of Apical Transportation in Four Ni-Ti Rotary Instrumentation TechniquesJournal of Endodontics, 2003
- Shaping ability of Hero 642 rotary nickel-titanium instruments and stainless steel hand K-Flexofiles in simulated curved root canalsOral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 2001
- Shaping Ability of Three ProFile Rotary Instrumentation Techniques in Simulated Resin Root CanalsJournal of Endodontics, 2000
- An improved technique for the evaluation of root canal preparationJournal of Endodontics, 1999
- Cyclic fatigue testing of nickel-titanium endodontic instrumentsJournal of Endodontics, 1997
- Comparison of nickel-titanium and stainless steel hand-file instrumentation using computed tomographyJournal of Endodontics, 1996