1. Unit of Oral and Maxillofacial Medicine and Pathology University of Sheffield Sheffield UK
2. Department of Oral Pathology University of Benghazi Benghazi Libya
3. Facultad de Odontologia Universidad Andres Bello Viña del Mar Chile
4. Department of Pathology University of Cambridge Cambridge UK
5. Oral Pathology and Biology University of Pretoria Pretoria South Africa