| Affiliation: | 1. Department of Periodontology, Academic Center for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, Amsterdam, The Netherlands;2. Clinic for Dentistry, Bussum, The Netherlands;3. Department of Dentistry and Oral Hygiene, University of Groningen, Groningen, The Netherlands;4. Department of Medical Microbiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands;5. Clinic for Periodontology, Utrecht, The Netherlands |
