1. Fixed Prosthodontics Department, Faculty of Dentistry Mansoura University Mansoura Egypt
2. Production Engineering and Mechanical Design Department, Faculty of Engineering Mansoura University Mansoura Egypt
3. Fixed Prosthodontics Department, Faculty of Dentistry Delta University for Science and Technology Mansoura Egypt
4. Department of Oral Regenerative Medicine, Academic Centre for Dentistry Amsterdam (ACTA) Universiteit van Amsterdam and Vrije Universiteit Amsterdam The Netherlands