1. Division of Periodontology Department of Developmental and Surgical Sciences School of Dentistry University of Minnesota Minneapolis MN USA
2. Division of Endodontics School of Dentistry University of Minnesota Minneapolis MN USA
3. School of Oral Surgery Vita‐Salute San Raffaele University Milan Italy
4. Oral Pathology Laboratories Department of Diagnostic and Biological Sciences Division of Oral and Maxillofacial Pathology University of Minnesota Minneapolis MN USA