1. School of Dentistry, The University of Manchester; Department of Oral and Maxillofacial Surgery; Coupland III Building, Oxford Road Manchester UK M13 9PL
2. School of Dentistry, The University of Manchester; Cochrane Oral Health Group; Coupland 3 Building, Oxford Road Manchester UK M13 9PL
3. King's College London; Department of Oral Surgery, Dental Institute; Kings Denmark Hill Campus Bessemer Rd London UK SE5 9RW