'Open your mouth and say AAA': Flexible batteries could power 'smart' orthodontics

Researchers are planning clinical trials after creating thin, flexible batteries that could power ‘smart’ orthodontic braces.

The dental device, designed by researchers at the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia, would position two near-infrared LEDs and one lithium-ion battery on each tooth in a translucent, 3D-printed brace. 

The LEDs would provide localised light therapy, which can enhance regeneration and reduce the time and costs involved in corrective orthodontics. 

The braces would rely on new batteries created by the researchers. “After the incidents with the Samsung Galaxy 7 batteries exploding, we realised that traditional batteries in their current form and encapsulation don’t serve our purpose,” said Muhammad Hussain of KAUST, who led the study alongside PhD student Arwa Kutbee.

“So we redesigned the state-of-the-art lithium-ion battery technology into a flexible battery, followed by ‘biosafe’ encapsulation within the braces.”

The pair used dry etching to remove a silicon substrate from a battery, thinning it to 2.25mm x 1.7mm and making it flexible. They then encapsulated it in biocompatible soft polymers to prevent leaking, potentially making it safe for use in the mouth. Embryonic kidney cells were successfully cultured on the battery  to test its compatibility. The system is a preliminary prototype and the next step is clinical trials, said Hussain.

The research was reported in the journal Flexible Electronics.

This article appears in the November issue of Professional Engineering magazine.

Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.