1. Department of Periodontology and Synoptic DentistryCharité – Universitätsmedizin Berlin Berlin Germany
2. Department of Oral Health SciencesUniversity of Washington Seattle Washington
3. Department of Periodontology, Operative and Preventive DentistryUniversity Hospital Bonn Bonn Germany
4. College of Medical and Dental SciencesPeriodontal Research GroupUniversity of Birmingham Birmingham UK