Anas Sira, Nawar Naguib Nawar, Shehabeldin Mohamed Saber, Hyeon-Cheol Kim
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引用次数: 0
Abstract
Introduction: This study evaluated the effects of retrieval strategies of separated nickel-titanium (NiTi) files on the biomechanical behavior of endodontically treated teeth by finite element analysis (FEA).
Methods: Six FE models were created; IT: intact tooth, SF: simulated a scenario where the apical 3 mm of a NiTi file is separated and retained, TD: simulated application of a trephine drill to expose 1 mm of the separated file, US180: simulated troughing of 180⁰ at the inner wall of root canal for an extra 1 mm of the separated file beyond the staging platform, US360: simulated circumferential ultrasonic troughing done for an extra 1 mm after the TD, and PM: simulated iatrogenic perforation sealed using MTA. Occlusal loading followed the occlusal fingerprint of the tooth before maximum von Mises stresses (vMS), maximum principal stresses (MPS), safety factor, and number of cycles (NCF) till failure were determined. Cervical region of the teeth and mid-root sections including the separated file were chosen as the areas of interest for further analysis.
Results: IT recorded the highest NCF and safety factor. Other models showed a narrow range of variation in all aspects with the PM recording the lowest NCF. The highest vMS was recorded at the mesiobuccal line angle of the PM near its cervical margin, while the lowest was found at the IT.
Conclusion: Under the limitation of this study, various file retrieval strategies removing the surrounding root dentin within the amounts of general guidelines do not affect the biomechanical behavior of the tooth.
期刊介绍:
The Journal of Endodontics, the official journal of the American Association of Endodontists, publishes scientific articles, case reports and comparison studies evaluating materials and methods of pulp conservation and endodontic treatment. Endodontists and general dentists can learn about new concepts in root canal treatment and the latest advances in techniques and instrumentation in the one journal that helps them keep pace with rapid changes in this field.