Premature failure of a jaw facial bone plate implant

Two factors have contributed to the increase of use of surgical orthopedic implants: the increase of the lifetime expectancy of the population and the higher risk of trauma occurrence associated to usual activities of modern life. Metallic materials designed for applications in surgical implants, no matter orthopedic or dental, must show a group of properties, in which biocompatibility, mechanical strength and resistance to degradation (by wear or corrosion) outstand. In order to reach these aims such materials must fulfill certain requirements, usually specified in standards, in relation to chemical composition, microstructure and even macrographic aspects. The main aim of this work is to perform the failure analysis of a plate designed for jaw facial osteosynthesis, installed in a victim of automotive crash. Mainly two techniques were employed in this work metallographic analysis by optical microscopy and fractographic analysis by scanning electron microscopy (SEM). The results obtained with such techniques allowed saying that the jaw facial implant failed by fatigue in a much shorter than predicted time, inferior to its lifetime expectancy.ch acted mainly on the region of the hole where the sliding screw was fitted, among other factors such as the difference between the implant design and the femoral geometry.