Design and Fabrication of Micro Saw Enabling Root-Side Cutting of Bone.

A novel micro saw was fabricated using a combination of photolithography and electroplating techniques, resembling a miniature timing belt with sideways blades. The rotation or oscillation direction of the micro saw is designed to be perpendicular to the cutting direction so that transverse cutting of the bone is attainable to extract a preoperatively planned bone-cartilage donor for osteochondral auto-graft transplantation. The mechanical property of the fabricated micro saw obtained using the nanoindentation test shows that the mechanical properties of the micro saw are almost an order of magnitude higher than bone, which indicates its potential bone-cutting application. To demonstrate the cutting capability of the fabricated micro saw, an in vitro animal bone cutting was performed using a custom test rig consisting of a microcontroller, 3D printer, and other readily available parts.