According to the American Academy of Otolaryngology – Head and Neck Surgery [AAO-HNS], hearing is a complex process that is dynamic in nature.
Vibrations from sound waves are transferred by the eardrum to three tiny bones in the middle ear. It is the stapes, commonly called the stirrup bone, that sets the inner ear fluids in motion, starting the sensory process of hearing.
Challenges:
NIH’s National Institute on Deafness and Other Communication Disorders explains that otosclerosis is an abnormal hardening of body tissue. In the lifelong regeneration of new bone tissue, occasionally abnormal “remodeling” of bone occurs. If the abnormal bone remodeling is around the stapes bone, it will become fixed, which inhibits its ability to generate the vibrations needed for proper hearing.
Solutions:
At Potomac Photonics, experts in micro-manufacturing solutions, the team are finding many unique applications to micro 3D print small implantable prosthetics using the ProJet Multi Jet (MJP) 3D printer. In one recent project they were asked to make the tiny elements of the middle ear to help develop prosthesis for otosclerosis disease. 3D printing is frequently in the news as a process for manufacturing prostheses to replace lost limbs, with the combination of 3D scanning, it allows designers to create prosthetics customized to each patient’s unique physical requirements.
They used MultiJet printing technology to deliver robust, durable high-quality plastic parts and has accuracy of layers as small as 32 microns. These ProJet MJP 3D Printers are neat and clever platform, they are easy to use and have a range of material choices including ABS-like plastic; translucent, blue and black materials; and choices of high-strength, highly flexible and very tough plastics. This makes it a very good platform for highly accurate prototypes and end use parts of many kinds and sizes, including automotive, aerospace, and, of course, medical devices.
Benefits:
Monika Kwacz, a researcher at the Institute of Micromechanics and Photonics at Warsaw Technical University in Poland, explains, ““Intuitively, it seemed to me that 3D printing would be the best technology for first prototyping. We need the first prototypes to experimentally verify that the device geometry was well designed and we will be able to implant the device in a temporal bone. If the geometry is good, then we will check the mechanical operation of the device. However, if we find we do need to modify the device geometry, 3D printing provides an easy way to modify in the CAD design step.”
Monika had tried another 3D printing process but it could not meet the precise requirement of the stapes design. Using a 3D Systems ProJet MJP high-resolution 3D printer, Potomac was able to get the very small, precise geometries she needed with tight tolerances. Turnaround, even shipping across the pond to Europe, was quick.
Given the small size of the parts, short 3D printed production runs may also be economically viable once the design is proven. In the meantime, Potomac Photonics will be working with Monika to micro 3D print a solution that will literally bring music to the ears of many otosclerosis suffers.