1. Division of Operative Dentistry and Biomaterials, Department of Restorative SciencesUniversity of North Carolina School of Dentistry Chapel Hill North Carolina
2. Operative Dentistry and Cariology, Faculty of Odontology, Division of Health SciencesUniversity of Iceland Reykjavic Iceland
3. Division of Operative Dentistry, Department of Restorative DentistryUniversity of Florida School of Dentistry Gainesville Florida