1. Groningen University, University Medical Center Groningen, Antonius Deusinglaan 1, Groningen 9713 AW, The Netherlands
2. Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Reymonta 25, Krakow 30-059, Poland
3. Dept. Dental Biomedical Sciences, Faculty of Dentistry, Universitas Gadjah Mada, Jalan Denta 1, Sekip Utara, Yogyakarta 55281, Indonesia