Opto-magnetic imaging spectroscopy in analyzing rotary NiTi endodontic instruments

Milica Jovanović-Medojević; Aleksandra Dragičević; Ivana Milanović; Lidija Matija; Slavoljub Živković

doi:10.1016/j.jmbbm.2023.105789

Opto-magnetic imaging spectroscopy in analyzing rotary NiTi endodontic instruments

J Mech Behav Biomed Mater. 2023 May:141:105789. doi: 10.1016/j.jmbbm.2023.105789. Epub 2023 Mar 23.

Authors

Milica Jovanović-Medojević¹, Aleksandra Dragičević², Ivana Milanović³, Lidija Matija⁴, Slavoljub Živković⁵

Affiliations

¹ University of Belgrade, School of Dental Medicine, Department for Restorative Dentistry and Endodontics, Rankeova 4, 11000, Belgrade, Serbia. Electronic address: medojevic.milica@gmail.com.
² University of Belgrade, Faculty of Mechanical Engineering, Department for Biomedical Engineering, Kraljice Marije 16, 11120, Belgrade, Serbia. Electronic address: adragicevic@mas.bg.ac.rs.
³ University of Belgrade, School of Dental Medicine, Department for Restorative Dentistry and Endodontics, Rankeova 4, 11000, Belgrade, Serbia. Electronic address: iv.bosnjak@gmail.com.
⁴ University of Belgrade, Faculty of Mechanical Engineering, Department for Biomedical Engineering, Kraljice Marije 16, 11120, Belgrade, Serbia. Electronic address: matijalidija@gmail.com.
⁵ University of Belgrade, School of Dental Medicine, Department for Restorative Dentistry and Endodontics, Rankeova 4, 11000, Belgrade, Serbia. Electronic address: slavzivkovic@gmail.com.

PMID: 36989872
DOI: 10.1016/j.jmbbm.2023.105789

Abstract

Intra-canal fracture of rotary NiTi instruments occurs due to torsional stress, cyclic fatigue, or a combination of these two factors. Broken instruments are a serious obstacle to shaping, cleaning, and filling of the root canal and can adversely affect the outcome of endodontic therapy. The aim of this study was to examine the magnetic properties and ultrastructural changes of new, used, and fractured NiTi instruments using opto-magnetic imaging spectroscopy (OMIS). The study included three sets of different types of rotary instruments: MTwo (VDW, Munich, Germany), Pro Taper Universal (Dentsply Maillefer, Ballaigues, Switzerland), and BioRace (FKG DENTAIRE Swiss Dental Products, Le Crêt-du-Locle Switzerland). Root canal shaping was performed on root canals with different curvatures, and after intra-canal fracture, instruments of the same type (new, used, and fractured) were analyzed using OMIS at the Faculty of Mechanical Engineering, University of Belgrade. The obtained results showed a coincidence of peak localization for the used instruments that did not suffer a fracture, as well as for new, unused instruments of all examined groups. Additionally, there was a coincidence of peak intensities for new and fractured instruments in all groups. The specific treatment of electropolishing of the active surface of BioRace instruments caused a completely different electromagnetic response compared to conventional NiTi sets of tested instruments. New, unused BioRace instruments had the most pronounced positive (5.6078 n.a.u. x1000) and negative (-8.5218 n.a.u. x1000) intensity values. The analysis of NiTi instruments using opto-magnetic imaging spectroscopy indicated changes in the magnetic properties after their instrumentation.

Keywords: Fractures of NiTi instruments; NiTi instruments; OMIS.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Dental Alloys
Equipment Design
Equipment Failure
Magnetic Phenomena
Materials Testing
Root Canal Preparation*
Rotation
Spectrum Analysis
Titanium* / chemistry

Substances

titanium nickelide
Titanium
Dental Alloys