1. Doctoral School of Dentistry, Organizing Institution of University Doctoral Studies, “Titu Maiorescu” University, 67A Gh. Petrascu Street, 040441 Bucharest, Romania
2. Faculty of Dental Medicine, “Titu Maiorescu” University, 67A Gh. Petrascu Street, 040441 Bucharest, Romania
3. Department of Mechanics and Strength of Materials, Faculty of Mechanical Engineering, Politehnica University of Timisoara, No.1 Mihai Viteazu Avenue, 300222 Timisoara, Romania
4. Faculty of Material Science and Engineering, Politehnica University of Bucharest, 313 Splaiul Independentei, District 6, 060042 Bucharest, Romania