1. Professor, Preventive Dentistry Department, Faculty of Dentistry, Jordan University of Science and Technology, Irbid, Jordan.
2. Master student, Preventive Dentistry Department, Faculty of Dentistry, Jordan University of Science and Technology, Irbid, Jordan.
3. Assistant Professor, Preventive Dentistry Department, Faculty of Dentistry, Jordan University of Science and Technology, Irbid, Jordan.
4. Associate Professor, Department of Prosthodontics, Faculty of Dentistry, University of Jordan, Amman, Jordan.