1. Department of Oral and Maxillofacial Surgery, University of Groningen, University Medical Center Groningen, The Netherlands. k.delli@umcg.nl
2. Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, The Netherlands.
3. Department of Oral and Maxillofacial Surgery, University of Groningen, University Medical Center Groningen, The Netherlands.
4. Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, The Netherlands.