1. Mucosal and Salivary Biology Division Dental Institute King's College London London U.K.
2. Oral and Maxillofacial Pathology King Abdulaziz University Jeddah Saudi Arabia
3. Biostatistics and Research Methods Centre Dental Institute King's College London London U.K.
4. St John's Institute of Dermatology Guy's and St Thomas's NHS Foundation Trust London U.K.