Related Experiment Video
Updated: May 4, 2026

Force System with Vertical V-Bends: A 3D In Vitro Assessment of Elastic and Rigid Rectangular Archwires
Published on: July 24, 2018
Assessing the MR compatibility of dental retainer wires at 7 Tesla
Joep Wezel1, Bert Jan Kooij, Andrew G Webb
1Department of Telecommunications, Delft University of Technology, Delft, The Netherlands; C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.
Purpose:
To determine the MR compatibility of common dental retainer wires at 7 Tesla in terms of potential RF heating and magnetic susceptibility effects.
Methods:
Electromagnetic simulations and experimental results were compared for dental retainer wires placed in tissue-mimicking phantoms. Simulations were then performed for a human model with wire in place. Finally, image quality was assessed for different scanning protocols and wires.
Results:
Simulations and experimental data in phantoms agreed well, with the length of the wire correlating to maximum heating in phantoms being approximately 47 mm. Even in this case, no substantial heating occurs when scanning within the specific absorption rate (SAR) guidelines for the head. Image distortions from the most ferromagnetic dental wire were not significant for any brain region.
Conclusion:
Dental retainer wires appear to be MR compatible at 7 Tesla.
Related Concept Videos
Magnetic Field Due to Two Straight Wires
Thermal expansion and Thermal stress: Problem Solving
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55...
Magnetic Field Due To A Thin Straight Wire
Magnetic Resonance Imaging

