Revolutionary 3D printing technology may offer the key to helping deaf people to hear, without the need for hearing aids.
Experts can now craft replacement parts for fragile bones, known as ossicles, which transmit external soundwaves towards the cochlear nerve.
The researchers hope that these personalised devices could soon make hearing aids a thing of the past.
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Revolutionary 3D printing technology may offer the key to helping deaf people to hear, without the need for hearing aids. Experts can now craft replacement parts for fragile bones, known as ossicles, which transmit external soundwaves towards the cochlear nerve
The researchers removed the ossicles from three dead bodies and took a CT scan to get specific measurements.
They then used a 3D printer to create replicas to replace the bones they had removed.
The prostheses were made from a resin that hardens when exposed to ultraviolet laser light.
Four surgeons were part of a blind study where they inserted each prosthesis into each middle ear, with no idea which corpse it had been designed to fit.
They were asked to match each prosthesis to its correct source, without any previous knowledge.
All four were able to correctly match the prosthesis model to its intended recipient.
Researchers at the University of Maryland in Baltimore came up with the concept, which uses CT scans of a patient's ear to create a 3D printed prosthetic.
Currently, surgeons create them in the operating room, but they often fail because they don't fit correctly.
By using CT imaging, the team was able to take detailed measurements of an individual's inner ear and use a standard 3D printer to create the bespoke synthetic bones.
Dr Jeffrey Hirsch, co-author of the study, said: 'The ossicles are very small structures, and one reason the surgery has a high failure rate is thought to be due to incorrect sizing of the prostheses.
'If you could custom-design a prosthesis with a more exact fit, then the procedure should have a higher rate of success.'
Hearing works through the transmission of vibrations from the outside world into the ear drum and on to the cochlea - the sensory organ of hearing.
The ear does this through three tiny bones in the middle ear known as ossicles.
The ability to personalise the plastic devices to create intricate prostheses, based on an individual's physiology, could make hearing aids a thing of the past. The new implant is smaller than a US penny and is inexpensive to make
Ossicles are three tiny bones in the middle-ear.
They are technically called the malleus, incus, and stapes, but are more commonly known as the hammer, anvil and stirrup.
The can become damaged from trauma or infection.
When damaged, sound is unable to travel from the