1. Ceramics Department, National Research Centre, Cairo, Egypt
2. Faculty of Engineering, Materials Engineering Deptartment, Zagazig University, Zagazig, Egypt
3. IFKB, University of Stuttgart, Stuttgart, Germany
4. Clinic of Orthopedics and Traumatology, Musculoskeletal Research Laboratory, University Hospital Freiburg, Clinic of Surgery, Freiburg, Germany