Page 161 - FINAL COMPENDIUM 2020-2021 27.2.2022

MICRO-COMPUTED TOMOGRAPHY EVALUATION OF DENTINAL MICROCRACKS
FOLLOWING CANAL PREPARATION WITH THERMOMECHANICALLY HEAT-TREATED
ENGINE-DRIVEN FILE
NMRR-18-4021-43308

Arumugam S, Hsu ZY, Safura Anita B, Jasmina QZ, Andanastuti M, Kanagasingam S
Objective: To evaluate and compare the frequency of microcracks and its severity at
different root canal dentin locations, after preparation with thermomechanically heat-
treated engine-driven nickel-titanium instruments. Materials and methods: Forty
mandibular premolars were assigned to four experimental groups (n=10): ProTaper Next,
ProTaper Gold, WaveOne Gold, and Reciproc Blue. After pre-instrumentation micro-
computed tomography scans, the root canals were prepared to size 25. Following post-
instrumentation scans, pre- and post-instrumentation scanned images were analysed for
the presence and extent of dentinal defects. Results: A total of 56,500 cross-sectional
images was obtained, showing that less than 2.3% with pre-existing dentinal microcracks.
No new microcracks were identified during the post-instrumentation analyses. No
significant association between the types of dentinal defects, file motions and sequences.
Thermomechanically heat-treated rotary files did not induce the formation of new
microcracks. Conclusion: There was also no association between the kinematic motions
and sequences of the rotary instruments to the types of dentinal defects.

Keywords: Dentinal defects, Dentinal microcracks, Nickel-titanium, Root canal preparation, X-Ray
Microtomography

Oral presentation at the 19 International Association for Dental Research MALSEC Annual Scientific Meeting on 10October

th
2020 at Acappella Suite Hotel
nd
Audience choice award for Basic Science Research at 2 Postgraduate Dental Symposium on 10-11 March 2020
Published in Australian Endodontic Journal/ Volume 47, Issue 3/ p. 520-530 on Dec 2021

Dr Sharmini Arumugam
Restorative Unit
Manir Dental Clinic Prof. Dr Andanastuti Muchtar
Kuala Terengganu Department of Mechanical & Manufacturing
Terengganu Engineering
Faculty of Engineering & Built Environment
AP Dr Hsu Zenn Yew The National University of Malaysia
AP Dr Safura Anita Baharin Bangi, Selangor
Dr Jasmina Qamaruz Zaman
Department of Restorative Dentistry Dr Shalini Kanagasingam
Faculty of Dentistry Faculty of Clinical and Biomedical Sciences
The National University of Malaysia School of Dentistry
Bangi, Selangor University of Central Lancashire
Preston, United Kingdom

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