1. Department of Periodontology and Oral Implantology, Faculty of Dentistry, Sebha University, Sebha, Libya
2. Department of Oral Pathology & Microbiology, Faculty of Dentistry, Sebha University, Sebha, Libya
3. Department of Oral and Maxillofacial Prosthodontics, Faculty of Dentistry, Jazan University, Jazan 45 142, Saudi Arabia
4. Department of Periodontics, Faculty of Dentistry, Arab Medical University, Benghazi, Libya
5. Department of Oral Biology and Orthodontics, Faculty of Dentistry, Sebha University, Sebha, Libya