Excessive wear of polyethylene in total replacement hip prostheses elicits deleterious biologic reactions and may be thus a limiting factor that compromises the long-term performance of these devices. This study is based on the report of two clinical failures of total hip prostheses with metallic femoral heads and polyethylene acetabular cups. The investigations reveal that foreign bodies (titanium fibermesh pieces) can migrate into the joint space of total hip prostheses and participate in abrasive third-body wear of the polyethylene cups. This excessive wear of polyethylene enhanced by the modification of the metallic counterface roughness is likely to induce the early loosening of the devices.