3D Printed Braces Incorporate Flexible Electronics for Faster Healing

I remember two main things about having braces as a child – they were frequently painful, and I seemed to have them forever. It was several years before I could get them taken off, and those years contained a lot of misery as the braces were repeatedly and painfully tightened. That’s something many, many kids – and occasionally adults – have had to go through, and it’s always been something that has been seen as uncomfortable but necessary. But now technology is making the process easier.

Near infrared (NIR) light therapy is a technique used for speeding healing and relieving pain. Cells have receptors that respond to near infrared wavelengths, and NIR energy is capable of penetrating deeply into the body and stimulating cell growth and regeneration while reducing inflammation. NIR therapy is sometimes used in dental and orthodontic treatments to accelerate the rate of bone regeneration, and a group of researchers at King Abdullah University of Science and Technology (KAUST) have used 3D printing to incorporate NIR therapy directly into dental braces themselves.

The 3D printed smart brace was created from a semi-transparent material with a flexible LED array, powered by flexible, bio-safe batteries, embedded within. The work is documented in a paper entitled “Flexible and biocompatible high-performance solid-state micro-battery for implantable orthodontic system,” which you can read here.

“Integration of electronic devices in 3D printed dental aligners, as we have demonstrated here, is a pragmatic approach towards implementing a flexible electronic technology in personalized advanced healthcare, particularly in orthodontics,” said Muhammad Mustafa Hussain, an Associate Professor of Electrical Engineering at KAUST. “The next stage of our work will be to demonstrate diagnostics in the smart dental brace in which sensors are able to detect the pressure exerted by aligners on teeth. This might help orthodontists estimate the force required by aligners; thus providing both diagnostic and treatment capabilities in dental braces.”

A challenge was to find a non-toxic battery. Any lithium-based battery is unsuitable for use in a dental application, so the researchers developed non-toxic microscale flexible batteries instead. The batteries were connected to near-infrared LED arrays on a soft PET substrate, which was embedded in the 3D printed brace.

“Our flexile biocompatible lithium-ion battery can be transferred on polyethylene terephthalate (PET) and interconnected via aluminum engraved interconnections to create a battery module,” said Hussain. “During testing we found that the battery module exhibits minimal strain while most of the stress is experienced by the PET film.”

The brace is customizable, which is obviously necessary in orthodontic treatment, and provides sufficient external loading to stimulate healthy rebuilding of the bone structures. Meanwhile, the embedded NIR capabilities deliver targeted light therapy, promoting fast bone regrowth.

“The combination of both strategies in one single platform provides affordable, multifunctionality dental braces,” said Hussain. “Such capability enhances the bone regeneration significantly and reduces the overall cost and discomfort. Our future work will include integration of compliant soft-substrate-based LEDs and miniaturized ICs with enhanced wireless capability for smart gadget-based remote control for cleaning and therapy.”

Authors of the study include Arwa T. Kutbee, Rabab R. Bahabry, Kholod O. Alamoudi, Mohamed T. Ghoneim, Marlon D. Cordero, Amani S. Almuslem, Abdurrahman Gumus, Elhadj M. Diallo, Joanna M. Nassar, Aftab M. Hussain, Niveen M. Khashab,  and Muhammad M. Hussain.

Discuss this and other 3D printing topics at 3DPrintBoard.com or share your thoughts below.