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Updated: May 18, 2026

Electric and Magnetic Field Devices for Stimulation of Biological Tissues
Published on: May 15, 2021
Electric toothbrushes induce electric current in fixed dental appliances by creating magnetic fields
Takashi Kameda1, Kazuo Ohkuma, Nozomu Ishii
1Department of Orthodontics, Nippon Dental University School of Dentistry at Niigata, 1-8 Hamaura-cho, Chuo-ku, Niigata city, Niigata, Japan. tkameda@ngt.ndu.ac.jp
Abstract:
Magnetic fields can represent a health problem, especially low frequency electromagnetic fields sometimes induced by electric current in metallic objects worn or used in or on the body (as opposed to high frequency electromagnetic fields that produce heat). Electric toothbrushes are widely used because of their convenience, but the electric motors that power them may produce electromagnetic waves. In this study, we showed that electric toothbrushes generate low frequency (1-2000 Hz) magnetic fields and induce electric current in dental appliances (e. g. orthodontic and prosthetic appliances and dental implants). Current induced by electric toothbrushes might be dependent on the quantity and types of metals used, and the shape of the appliances. Furthermore, these induced currents in dental appliances could impact upon human oral health, producing pain and discomfort.
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