Manufacture of bone fracture plates based on glass fiber reinforced polyurethane composite: a gravity casting adapted process

The development of materials and devices to replace or restore damaged tissue functions has a prominent position in the scientific community, promoting the interest for metal-free alternatives, like composites. These proved to be a promising option as, besides new matrix and reinforcement combinations, new manufacturing methods tend to fulfil tailored requirements of the medical field. In this sense, we manufactured glass fiber/polyurethane composite plates for Osteosynthesis. Models based on commercial LCP implants were 3D printed and used to generated molds through a new adapted resin casting process. Additional mechanical tests showed that reinforcement additions between 10 wt% and 25 wt% caused an increase in the bending structural stiffness by 126%-165% when compared to pure polymer implants. In addition, if the number of holes is increased, from 4 to 6, the maximum stress reduces by 40%. The manufacturing process was an effective alternative as it presented low cost, high customization and allowed the development of complex geometries, resin injection and degassing.