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Failure Mechanism of Hedstroem Endodontic Files In Vivo

  • Spiros Zinelis
    Correspondence
    Address requests for reprints to Spiros Zinelis, Biomaterials Laboratory, University of Athens, School of Dentistry, 2 Thivon str. Goudi, 11527 Athens, Greece.
    Affiliations
    Dr. Zinelis is a metallurgical engineer, and Dr. Margelos is a research fellow, Biomaterials Lab, School of Dentistry, University of Athens, Athens, Greece.
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  • John Margelos
    Affiliations
    Dr. Zinelis is a metallurgical engineer, and Dr. Margelos is a research fellow, Biomaterials Lab, School of Dentistry, University of Athens, Athens, Greece.
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      Intracanal fracture of endodontic Hedstroem files (H-files) jeopardizes the outcome of endodontic therapy. The aim of this study was to evaluate the fracture mechanism of H-files after multiple in vivo uses. Five each of size #20 and #25 ISO H-files fractured during clinical use were collected from different dental clinics. Four fractured files of each size and three unused files of each corresponding size were embedded in a resin along their longitudinal axis and after metallographic grinding and polishing studied under an incident light microscope. One specimen in the fractured group was investigated under a scanning electron microscope. Light microscopy results showed that unused files were free of structural defects (cracks, pores, etc.), whereas fractured files demonstrated the presence of many cracks mostly located at the flute depth region. Secondary cracks were identified beyond the fracture plane of fractured files both with a light microscope and a scanning electron microscope. Experimental results demonstrated that fatigue is closely associated with the fracture mechanism of H-files (#20, #25) under clinical conditions.
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      References

        • Grossman LI
        Guidelines for the prevention of fracture of root canals instruments.
        Oral Surg Oral Med Oral Pathol. 1969; 28: 746-752
        • Wildey WL
        • Senia ES
        • Montgomery S
        Another look of root canal instrumentation.
        Oral Surg Oral Med Oral Pathol. 1992; 74: 499-507
        • Sotokowa T
        An analysis of clinical breakage of root canal instruments.
        J Endodon. 1988; 14: 75-82
        • Haikel Y
        • Serfaty R
        • Bleicher P
        • Lwin TT
        • Allemann C
        Effects of cleaning, chemical disinfection, sterilization procedures on the mechanical properties of endodontic instruments.
        J Endodon. 1997; 23: 15-18
        • Iverson GW
        • von Fraunhofer JA
        • Herrmann JW
        The effects of various sterilization methods on the torsional strength of endodontic files.
        J Endodon. 1985; 11: 266-268
        • Mitcell BF
        • James GA
        • Nelson RC
        The effects of autoclave sterilization on endodontic files.
        Oral Surg. 1983; 55: 204-207
        • Chernick LB
        • Jacobs JJ
        • Lautenschlager EP
        • Heuer MA
        Torsional failure of endodontic files.
        J Endodon. 1976; 2: 94-97
        • Schroeder A
        Endodontie. 2nd ed. Quintessenz Verlangs, Berlin1981
        • Younis O
        The effects of sterilization techniques on the properties of intracanal instruments.
        Oral Surg Oral Med Oral Pathol. 1977; 43: 130-134
        • Felhaber T
        The effects of repeated use and sterilization of certain properties of stainless steel endodontic files [master’s thesis]. Indiana University—Purdue University at Indianapolis, School of Dentistry, Indianapolis1969
        • Roulet J
        Dynamic fracture of conventional endodontic instruments versus experimental files.
        J Endodon. 1983; 9: 12-16
        • Smith WF
        Principles of materials science and engineering. 2nd ed. McGraw-Hill, New York1990: 304
        • McDonell V
        • Phillips A
        Modes of fracture.
        in: Fractography: ASM handbook. vol 12. ASM International, Materials Park, OH1987: 15 (29)
        • Tricard M
        Residual effects of finishing methods.
        in: Cotell CM Sprague JA Smidt FA Surface engineering: ASM handbook, vol 5. 2nd ed. ASM International, Materials Park OH1996: 144-157
        • Deutschman AD
        • Michels WJ
        • Wilson CE
        Machine design, theory, and practice. Macmillan, New York1975: 891-901
        • Sprowls DO
        Evaluation of corrosion fatigue.
        in: Corrosion: ASM handbook. vol 13. ASM International, Materials Park, OH1987: 291
        • Fraker AC
        Corrosion of metallic implants and prosthetic devices.
        in: Corrosion: ASM handbook. vol 13. ASM International, Materials Park, OH1987: 1332
        • Smith C
        • Boardmen D
        Metals engineering.
        in: Boyer HE Gall T Metals handbook. American Society for Metals, Metals Park, OH1985: 2-3 (3–3)