1. Department of Cranio-Maxillofacial and Oral Surgery, Yekatit 12 Hospital Medical College, Addis Ababa, Ethiopia
2. Department of Pediatrics and Child Health, Addis Ababa University, Addis Ababa, Ethiopia
3. Dental and Stomatology, Haramaya University, Harar, Ethiopia
4. Department of Pathology, Addis Ababa University, Addis Ababa, Ethiopia
5. Department of Oral and Maxillofacial Surgery, Military Hospital Ulm, Academic Hospital Ulm University, Ulm, Germany