Micro-machining of bovine bone for otologic applications

Prosthetics in otology plays a significant role in restoring the structures damaged by traumas or pathologies. The aim of this work is to propose a new approach to manufacture and to control the finishing of bone mini-devices for otologic applications through a combined use of CAD/CAM and CNC.Indeed, micromanufacturing can improve the fabrication process of bone components with respect to the traditional hand-sculpting approaches. After a description of the preliminary studies carried out to define the best cutting parameters for bovine bone, this study focused on the manufacturing process and quality, by an ex-post analysis, of two bone structures useful for reconstructive surgery: the external auditory canal wall and the modified incus to be repositioned during ossiculoplasty. In the first case, a microCT analysis showed a flaw that led to a decrease of the thickness, which was compensated and controlled on a second prototype. As for the incus, due to its tiny dimensions few detachments of the material were noticed on the surface which needed a further step of refining to accomplish the surgeons’ specifications. This new approach, based on innovative manufacturing technologies, may represent a significant advancement towards industrially reliable approaches to produce new biocompatible devices in the otologic field. Micro-machining, bone, micro-prostheses, biomaterials, bioengineering