1. Department for Radiography and Dental Technology Programs; Oslo and Akershus University College of Applied Sciences; Oslo Norway
2. Menzies Health Institute Queensland; Population and Social Health Research Programme; Griffith University; Gold Coast Qld Australia
3. Division of Restorative Dentistry and Periodontology; Dublin Dental University Hospital; Trinity College Dublin; Dublin Ireland
4. School of Dentistry and Oral Health; Griffith University; Gold Coast Qld Australia