A new human middle ear model for the biomechanical evaluation of a prosthesis for the ossicular chain reconstruction

The middle ear is a sophisticated mechanism which transmits sound waves from the outer ear to the inner ear, while it amplifies and filters the sound waves depending on their frequency. However, the sound path can be broken due to traumas, infections, ossification or alteration. In this case, the surgeons reconstruct the sound path with an implant, mostly with passive titanium prostheses. Developers need an environment to validate these implants. The current environment for this purpose is the human temporal bone from cadavers, which does not provide reproducible conditions for experiments. In this paper, we present a new anatomical human middle ear model. We have segmented the essential functional elements from μCT-data (micro computed tomography). We have reproduced the bony structures with a 3D printer and the soft tissues with silicone rubber casting. Our experiments show that the model transmits the sound waves from the tympanic membrane to the inner ear as in a human middle ear. We also present that the articulated ossicles are suitable to reconstruct the ossicular chain with different types of passive prostheses.