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VOLUME 18 , ISSUE 3 ( March, 2017 ) > List of Articles

RESEARCH ARTICLE

Flute and Shank Dimensions of Reciprocating Instruments before and after Simulated Root Canal shaping

Carlos Estrela, Felipe C Sampaio, Ana PP Brito, Heloisa HP Veloso, Ana HG de Alencar, Daniel de A Decurcio, José AP de Figueiredo

Citation Information : Estrela C, Sampaio FC, Brito AP, Veloso HH, de Alencar AH, de A Decurcio D, de Figueiredo JA. Flute and Shank Dimensions of Reciprocating Instruments before and after Simulated Root Canal shaping. J Contemp Dent Pract 2017; 18 (3):198-204.

DOI: 10.5005/jp-journals-10024-2016

Published Online: 00-03-2017

Copyright Statement:  Copyright © 2017; Jaypee Brothers Medical Publishers (P) Ltd.


Abstract

Aim

This study analyzed the effect of the dimensions of the flute and shank in the first 4 mm of instrument tips on the deformation and dimensional changes of reciprocating instruments after root canal shaping (RCS).

Materials and methods

The reciprocating instruments used were Reciproc® R25, R40, and R50; WaveOne® Small, Primary, and Large; and Unicone® #20, #25, and #40. Scanning electron microscopy images of the first 4 mm of the tip were acquired at 30× magnification before and after simulated curved root canals were shaped. Each instrument was used only once. The images were transferred to the AxioVision® software to measure the flute area (µm2, shank area (µm2), flute length (µm), and crosssectional diameter (µm). Student's t test for paired samples was used to compare differences before and after RCS, and analysis of variance followed by the Tukey test, to compare differences between instruments of similar sizes. The instruments were classified according to deformations after RCS.

Results

Reciproc® instruments had larger flutes and smaller shanks. The Reciproc® R40 had significant differences in crosssectional diameter at 0.5 mm from the tip. Reciproc® had no plastic deformations. Unicone® #20 instruments had significant differences in cross-sectional diameter at 1.5 and 3.0 mm from the tip, and #25 instruments had differences at 1.5 and 3.0 mm and in length of the second and third flutes. One #20 and three #40 instruments had plastic deformations. The differences in length of the first and fourth flutes of WaveOne® Primary and in cross-sectional diameter at 2.0 mm from the tip of WaveOne® Large were significant. Two of three WaveOne® Large instruments had plastic deformations.

Conclusion

Reciproc® instruments had greater flute areas and lengths and smaller shanks than Unicone® and WaveOne® instruments of similar sizes. Reciproc® instruments had a greater flute-to-shank ratio. WaveOne® instruments had the lowest flute-to-shank ratio. Unicone® instruments had the most plastic deformations. Instruments with larger flutes and smaller shanks had fewer plastic deformations after curved RCS.

Clinical significance

The knowledge of mechanical behavior before choosing the endodontic instrument may avoid fracture, regardless of the clinical condition, and it is essential to the success of root canal treatment.

How to cite this article

Sampaio FC, Brito APP, Veloso HHP, Alencar AHG, Decurcio DA, Figueiredo JAP, Estrela C. Flute and Shank Dimensions of Reciprocating Instruments before and after Simulated Root Canal shaping. J Contemp Dent Pract 2017;18(3):198-204.


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  1. Cleaning and shaping the root canal. Dent Clin North Am 1974 Apr;18(2):269-296.
  2. Characterization of successful root canal treatment. Braz Dent J 2014 Jan-Feb;25(1):3-11.
  3. Assessment of the apical transportation of root canals using the method of the curvature radius. Braz Dent J 1998;9(1):39-45.
  4. Cleaning effectiveness and shaping ability of rotary ProTaper compared with rotary GT and manual K-Flexofile. Am J Dent 2006 Dec;19(6):353-358.
  5. An initial investigation of the bending and torsional properties of Nitinol root canal files. J Endod 1988 Jul;14(7):346-351.
  6. An analysis of endodontic treatment with three nickel-titanium rotary root canal preparation techniques. Int Endod J 2004 Dec;37(12):849-859.
  7. Analysis of Mtwo rotary instrument separation during endodontic therapy: a retrospective clinical study. Cell Biochem Biophys 2014 Nov;70(2):1091-1095.
  8. Evolution of nickel-titanium instruments: from past to future. ETP Endod Topics 2013 Sep;29(1):3-17.
  9. Effects of electropolishing surface treatment on the cyclic fatigue resistance of BioRace nickel-titanium rotary instruments. J Endod 2010 Oct;36(10):1653-1657.
  10. Current challenges and concepts of the thermomechanical treatment of nickel-titanium instruments. J Endod 2013 Feb;39(2):163-172.
  11. Canal preparation using only one Ni-Ti rotary instrument: preliminary observations. Int Endod J 2008 Apr;41(4):339-344.
  12. An evaluation of the Giromatic endodontic handpiece. Oral Surg Oral Med Oral Pathol 1967 Sep;24(3):419-421.
  13. The effect of Giromatic files on the preparation shape of severely curved canals. Int Endod J 1987 May;20(3):133-142.
  14. Fatigue life of Reciproc and Mtwo instruments subjected to static and dynamic tests. J Endod 2013 May;39(5):693-696.
  15. Extended cyclic fatigue life of F2 ProTaper instruments used in reciprocating movement. Int Endod J 2010 Dec;43(12):1063-1068.
  16. A comparison of cyclic fatigue resistance in reciprocating and rotary nickel-titanium instruments. Aust Endod J 2011 Dec;37(3):122-127.
  17. Resistance to flexural fatigue of Reciproc R25 files under continuous rotation and reciprocating movement. J Endod 2012 May;38(5):684-687.
  18. Bending resistance and dynamic and static cyclic fatigue life of Reciproc and WaveOne large instruments. J Endod 2014 Apr;40(4):575-579.
  19. Single file reciprocating technique using conventional nickel-titanium rotary endodontic files. Scanning 2013 Nov-Dec;35(6):349-354.
  20. Influence of continuous or reciprocating motion on cyclic fatigue resistance of 4 different nickel-titanium rotary instruments. J Endod 2013 Feb;39(2):258-261.
  21. Is the reciprocating movement per se able to improve the cyclic fatigue resistance of instruments? Int Endod J 2014 May;47(5):430-436.
  22. Fatigue life enhancement of NiTi rotary endodontic instruments by progressive reciprocating operation. Int Endod J 2014 Sep;47(9):882-888.
  23. An overview of the mechanical properties of nickel-titanium endodontic instruments. Endod Topics 2013 Sep;29(1):42-54.
  24. Deformation and fracture incidence of Reciproc instruments: a clinical evaluation. Int Endod J 2015 Feb;48(2):199-205.
  25. Assessment of the separation incidence of reciprocating WaveOne files: a prospective clinical study. J Endod 2014 Jul;40(7):922-924.
  26. Incidence of dentinal defects after root canal preparation: reciprocating versus rotary instrumentation. J Endod 2013 Apr;39(4):501-504.
  27. Comparison of 2 canal preparation techniques in the induction of microcracks: a pilot study with cadaver mandibles. J Endod 2014 Jul;40(7):982-985.
  28. Root surface strain during canal shaping and its influence on apical microcrack development: a preliminary investigation. Int Endod J 2015 Dec;48(12):1103-1111.
  29. Dentinal crack formation during root canal preparations by the twisted file adaptive, ProTaper Next, ProTaper Universal, and WaveOne instruments. J Endod 2015 Feb;41(2):261-264.
  30. Morphometric analysis of shank-to-flute ratio in rotary nickel-titanium files. Int Endod J 2004 Jun;37(6):353-358.
  31. Relationship between design features of endodontic instruments and their properties. Part 3. Resistance to bending and fracture. J Endod 2001 Apr;27(4):299-303.
  32. Cyclic fatigue and torsional resistance of two new nickel-titanium instruments used in reciprocation motion: Reciproc versus WaveOne. J Endod 2012 Apr;38(4):541-544.
  33. Cyclic fatigue resistance of 3 different nickel-titanium reciprocating instruments in artificial canals. J Endod 2015 Jun;41(6):913-915.
  34. Cutting efficiency of Reciproc and WaveOne reciprocating instruments. J Endod 2014 Aug;40(8):1228-1230.
  35. Mechanical preparation of root canals: shaping goals, techniques and means. Endod Topics 2005 Mar;10(1):30-76.
  36. Instrument fracture: mechanisms, removal of fragments, and clinical outcomes. ETP Endod Topics 2009;16(1):1-26.
  37. Endodontic instrument fracture: causes and prevention. Br Dent J 2013 Apr;214(7):341-348.
  38. Prevalence and extent of long oval canals in the apical third. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000 Jun;89(6):739-743.
  39. Assessment of dentinal tubule invasion capacity of Enterococcus faecalis under stress conditions ex vivo. Int Endod J 2015 Apr;48(4):362-372.
  40. Cyclic fatigue of Reciproc and WaveOne reciprocating instruments. Int Endod J 2012 Jul;45(7):614-618.
  41. Elastic limits in torsion of reciprocating nickel-titanium instruments. J Endod 2015 May;41(5):715-719.
  42. Lack of correlation between obturation limits and apical leakage. Braz Oral Res 2013 Jul-Aug;27(4):331-335.
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