1 Department of Maxillofacial and Oral Surgery, Faculty of Health Sciences, Chris Hani Baragwanath Hospital, University of the Witwatersrand, Johannesburg, South Africa. Electronic address: ferretti@mweb.co.za.
2 Department of Maxillofacial and Oral Surgery, University of the Western Cape, Cape Town, South Africa; Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Oklahoma, Oklahoma City, OK, USA; Department of Oral and Maxillofacial Surgery, College of Dentistry, University of Florida, Gainesville, FL, USA; Division of Oral and Maxillofacial Surgery, Universidad Autonoma de Nueva Leon, Monterrey, Mexico.