1. Ribeirão Preto Dental School, University of São Paulo; Department of Dental Materials and Prosthodontics; Av. Do Café, s/n Ribeirão Preto São Paulo (SP) Brazil 14040-904
2. Stoke Mandeville Hospital; Department of Orthodontics; Mandeville Road Aylesbury UK HP21 8AL
3. KCL Dental Institute; Division of Health and Social Care Research; Bessemer Road London UK SE5 9RW
4. Nova Southeastern University; Dentistry; 3200 South University Drive Fort Lauderdale Florida USA 33328-2018