The new dental appliance contains magnetic field sensors mounted on its four corners that detect movement of a tiny magnet attached to the tongue. It also includes a rechargeable lithium-ion battery and an induction coil to charge the battery. The circuitry fits in the space available on the retainer, which sits against the roof of the mouth and is covered with an insulating, water-resistant material and vacuum-molded inside standard dental acrylic.
“One of the problems we encountered with the earlier headset was that it could shift on a user’s head and the system would need to be recalibrated,” explained Ghovanloo. “Because the dental appliance is worn inside the mouth and molded from dental impressions to fit tightly around an individual’s teeth with clasps, it is protected from these types of disturbances.”
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