1. Faculty of Medicine, Clinic of Stomatology, Department of Prosthodontics, Niš, Serbia and Montenegro
2. Faculty of Medicine, Institute of Biology, Niš, Serbia and Montenegro
3. Faculty of Medicine, Niš, Institute of Biochemical Research, Niš, Serbia and Montenegro
4. Faculty of Medicine, Institute of Pathology, Niš, Serbia and Montenegro
5. Faculty of Medicine, Clinic of Stomatology, Department of Maxillofacial Surgery, Niš, Serbia and Montenegro
6. Institute of Technical Sciences of the Serbian Academy of Sciences and Arts, K. Mihailova 35/IV, 11000, Belgrade, Serbia and Montenegro
7. Institute of Technical Sciences of the Serbian Academy of Sciences and Arts, K. Mihailova 35/IV, 11000, Belgrade, Serbia and Montenegro,