Open Access, Peer-reviewed
eISSN 2234-7666
    J Korean Acad Conserv Dent. 2011 May;36(3):231-237. Korean.
    Published online May 31, 2011.
    https://doi.org/10.5395/JKACD.2011.36.3.231
    Copyright © 2011 Korean Academy of Conservative Dentistry
    Original Article

    Evaluation of apical canal shapes produced sequentially during instrumentation with stainless steel hand and Ni-Ti rotary instruments using Micro-computed tomography

    Woo-Jin Lee, DDS, MSD, Graduate Student ,1 Jeong-Ho Lee, DDS, PhD,1 Kyung-A Chun, DDS, MSD, Clinical Associate Professor ,2 Min-Seock Seo, DDS, MSD, Clinical Professor ,3 Yeon-Jee Yoo, DDS, Resident ,1 and Seung-Ho Baek, DDS, PhD, Associate Professor 1
      • 1Department of Conservative Dentistry and Dental Research Institute, College of Dentistry, Seoul National University, Seoul, Korea.
      • 2Department of Conservative Dentistry, Korea University Anam Hospital, Seoul, Korea.
      • 3Hanyang University Seoul Hospital, Seoul, Korea.
    • Correspondence to Seung-Ho Baek, DDS, PhD. Associate Professor, Department of Conservative Dentistry and Dental Research Institute, Seoul National University College of Dentistry, 28-2 Yeongeon-dong, Jongro-gu, Seoul, Korea 110-749. TEL, +82-2-2072-3951; FAX, +82-2-2072-3850; Email: shbaek@snu.ac.kr
    Received April 11, 2011; Revised April 27, 2011; Accepted April 29, 2011.

    Abstract

    Objectives

    The purpose of this study was to determine the optimal master apical file size with minimal transportation and optimal efficiency in removing infected dentin. We evaluated the transportation of the canal center and the change in untouched areas after sequential preparation with a #25 to #40 file using 3 different instruments: stainless steel K-type (SS K-file) hand file, ProFile and LightSpeed using microcomputed tomography (MCT).

    Materials and Methods

    Thirty extracted human mandibular molars with separated orifices and apical foramens on mesial canals were used. Teeth were randomly divided into three groups: SS K-file, Profile, LightSpeed and the root canals were instrumented using corresponding instruments from #20 to #40. All teeth were scanned with MCT before and after instrumentation. Cross section images were used to evaluate canal transportation and untouched area at 1- , 2- , 3- , and 5- mm level from the apex. Data were statistically analyzed according to' repeated nested design'and Mann-Whitney test (p = 0.05).

    Results

    In SS K-file group, canal transportation was significantly increased over #30 instrument. In the ProFile group, canal transportation was significantly increased after preparation with the #40 instrument at the 1- and 2- mm levels. LightSpeed group showed better centering ability than ProFile group after preparation with the #40 instrument at the 1 and 2 mm levels.

    Conclusions

    SS K-file, Profile, and LightSpeed showed differences in the degree of apical transportation depending on the size of the master apical file.

    Keywords
    LightSpeed; Master apical file; Micro CT, ProFile; Stainless steel K-file; Transportation

    Figures

    Figure 1
    Measuring the distance and the angle between original center and deviated center. a: original center of the canal. b: deviated center after preparation. Canal transportation (by distance) : Distance between a and b. Canal transportation (by degree) : A positive value indicates a movement of the canal center in the outer root surface (purple arrow), while a negative value signifies a shift in the opposite direction (green arrow).

    * Original canal wall was drawn by red line and canal wall after preparation by black line.

    Figure 2
    Cross sectional images acquired by µCT illustrate the sequential canal deviation by each group of instrument. Profile and Lightspeed group show more round and less deviated canal shapes.

    Figure 3
    Mean displacement of the canal centers according to the file size and instrument type at each level (µm).

    Figure 4
    Changes of untouched areas of canal space are demonstrated (%SD).

    Notes

    This study was supported by the Seoul National University research fund for new faculty.

    References

      1. Kerekes K, Tronstad L. Morphometric observations on the root canals of human molars. J Endod 1977;3:114–118.
      1. Gani O, Visvisian C. Apical canal diameter in the first upper molar at various ages. J Endod 1999;25:689–691.
      1. Short JA, Morgan LA, Baumgartner JC. A comparison of canal centering ability of four instrumentation techniques. J Endod 1997;23:503–507.
      1. Albrecht LJ, Baumgartner JC, Marshall JG. Evaluation of apical debris removal using various sizes and tapers of ProFile GT files. J Endod 2004;30:425–428.
      1. Rhodes JS, Ford TR, Lynch JA, Liepins PJ, Curtis RV. Micro-computed tomography: a new tool for experimental endodontology. Int Endod J 1999;32:165–170.
      1. Rhodes JS, Ford TR, Lynch JA, Liepins PJ, Curtis RV. A comparison of two nickel-titanium instrumentation techniques in teeth using microcomputed tomography. Int Endod J 2000;33:279–285.
      1. Bergmans L, Van Cleynenbreugel J, Wevers M, Lambrechts P. A methodology for quantitative evaluation of root canal instrumentation using microcomputed tomography. Int Endod J 2001;34:390–398.
      1. Schneider SW. A comparison of canal preparations in straight and curved root canals. Oral Surg Oral Med Oral Pathol 1971;32:271–275.
      1. Lee JH, Kim MJ, Seok CI. Evaluation of canal preparation with Ni-Ti rotary files by micro computed tomography. J Korean Acad Conserv Dent 2004;29:378–385.
      1. Bramante CM, Berbert A, Borges RP. A methodology for evaluation of root canal instrumentation. J Endod 1987;13:243–245.
      1. Ko HJ, Baek SH. A study of histomorphological change of curved root canal preparation using GT rotary file, profile and stainless steel K-file. J Korean Acad Conserv Dent 2002;27:612–621.
      1. Gluskin AH, Brown DC, Buchanan LS. A reconstructed computerized tomographic comparison of Ni-Ti rotary GT files versus traditional instruments in canals shaped by novice operators. Int Endod J 2001;34:476–484.
      1. Wu MK, Fan B, Wesselink PR. Leakage along apical root fillings in curved root canals. Part I: effects of apical transportation on seal of root fillings. J Endod 2000;26:210–216.
      1. Deplazes P, Peters O, Barbakow F. Comparing apical preparations of root canals shaped by nickel-titanium rotary instruments and nickel-titanium hand instruments. J Endod 2001;27:196–202.
      1. Thompson SA, Dummer PM. Shaping ability of Lightspeed rotary nickel-titanium instruments in simulated root canals. Part 2. J Endod 1997;23:742–747.
      1. Versümer J, Hülsmann M, Schäfers F. A comparative study of root canal preparation using Profile .04 and Lightspeed rotary Ni-Ti instruments. Int Endod J 2002;35:37–46.
      1. Iqbal MK, Maggiore F, Suh B, Edwards KR, Kang J, Kim S. Comparison of apical transportation in four Ni-Ti rotary instrumentation techniques. J Endod 2003;29:587–591.
      1. Ruddle CJ. Cleaning and shaping the root canal system. In: Cohen S, Burns RC, editors. Pathways of the pulp. 8th ed. St. Louis: C.V Mosby; 2002. pp. 231-245.
      1. Griffiths IT, Chassot AL, Nascimento MF, Bryant ST, Dummer PM. Canal shapes produced sequentially during instrumentation with Quantec SC rotary nickel-titanium instruments: a study in simulated canals. Int Endod J 2001;34:107–112.
      1. Peters OA, Laib A, Göhring TN, Barbakow F. Changes in root canal geometry after preparation assessed by high-resolution computed tomography. J Endod 2001;27:1–6.
      1. Kosa DA, Marshall G, Baumgartner JC. An analysis of canal centering using mechanical instrumentation techniques. J Endod 1999;25:441–445.
      1. Peters OA, Schönenberger K, Laib A. Effects of four Ni-Ti preparation techniques on root canal geometry assessed by micro computed tomography. Int Endod J 2001;34:221–230.
      1. Wu MK, Wesselink PR. A primary observation on the preparation and obturation of oval canals. Int Endod J 2001;34:137–141.
      1. Paqué F, Ganahl D, Peters OA. Effects of root canal preparation on apical geometry assessed by micro-computed tomography. J Endod 2009;35:1056–1059.
    Cited by
    Crossref 1
    Google Scholar 
    MeSH Terms
    Dental Pulp Cavity
    Dentin
    Hand
    Humans
    Molar
    Nickel
    Stainless Steel
    Titanium
    Tooth
    Tooth Apex
    Transportation
    X-Ray Microtomography
    Metrics
    Share
    Figures
    slide
    slide
    slide
    slide

    1 / 4

    PERMALINK