Institution: | a Department of Oral and MaxilloFacial Surgery, The Dental School, University of Newcastle, Framlington Place, Newcastle upon Tyne, Newcastle NE2 4BW, UK b Department of Anaesthetics, Royal Victoria Infirmary, Newcastle upon Tyne, Newcastle NE2 4BW, UK c School of Mathematics and Statistics, Merz Court, University of Newcastle, Newcastle NE2 4BW, UK |