1. Prof. Mark Woolford   Professor of Education in Dentistry,    St Thomas’ Hospital, Lambeth Palace Road,    London, SE1 7EH, United Kingdom

E-mail address: mark.woolford@kcl.ac.uk

2. Prof. M. Iwaku,

Professor of Nippon Dental University, Professor Emeritus of Niigata University, Division of Cariology, Department of Oral Health Science,   Niigata University Graduate School of Medical and Dental Sciences,

5274 Gakkochodori 2 bancho, 951-8514, Niigata, Japan. E-mail Address:hakuai-d@cronos.ocn.ne.jp

3. Professor Yahia Eltayib Ibrahim

Professor in Conservative dentistry, Faculty of Dentistry, University of Khartoum,     Khartoum, Sudan

E-mail Address: yeibrahim@yahoo.com

Address for correspondence:

Professor. NEAMAT HASSAN ABU-BAKR, BDS, DSS, MDSc, PhD

P.O. Box 694, Khartoum, 111-11, Khartoum, Sudan

Mobile Tel:  0912279332

E-mail address: nhabubakr@uofk.edu or neamat@yahoo.com