1. University of Bern; Department of Preventive, Restorative and Pediatric Dentistry; Freiburgstrasse 7 Bern Bern Switzerland CH-3010
2. Cochrane; Bahrain Branch; Box 25438 Awali Bahrain
3. Cardiff University School of Medicine; Institute of Primary Care & Public Health; 3rd Floor, Neuadd Meirionnydd, Heath Park Cardiff UK CF14 4YS
4. Plymouth University Peninsula Schools of Medicine and Dentistry; Peninsula Dental School; The John Bull Building, Tamar Science Park, Plymouth UK PL6 8BU
5. Ministry of Health; Oral and Dental Health Services; PO Box 12 Manama Bahrain