Synergistetes cluster A in saliva is associated with periodontitis Belibasakis GN, € Ozt € urk V- € O, Emingil G, Bostanci N. Synergistetes cluster A in saliva is associated with periodontitis. J Periodont Res 2013; doi: 10.1111/ jre.12061. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd Background and Objectives: Synergistetes is a novel bacterial phylum consisting of gram-negative anaerobes. Increasing lines of evidence demonstrate that this phylum is associated with periodontal diseases. This study aimed to compare the presence and levels of Synergistetes clusters A and B, in saliva of patients with chronic periodontitis (CP), generalized aggressive periodontitis (G-AgP) and non-periodontitis subjects, and investigate their correlation with clinical parameters. Material and Methods: Saliva was collected from patients with CP (n = 20), G-AgP (n = 21) and non-periodontitis subjects (n = 18). Full mouth clinical periodontal measurements were recorded. The numbers of Synergistetes cluster A and cluster B or the associated species Jonquetella anthropi were quantified by fluorescent in situ hybridization and microscopy. Results: Synergistetes cluster A bacteria were detected more frequently, and at higher numbers and proportions in the two periodontitis groups, than the non- periodontitis control group. The prevalence was 27.7% in the control group, 85% in CP and 86% in G-AgP. Compared to the control group, the numbers were significantly higher by 12.5-fold in CP and 26.5-fold in G-AgP, whereas the difference between the two forms of periodontitis was not statistically signifi- cant. Within the total bacterial population, the proportion of this cluster was increased in CP and G-AgP compared to the control group, with the difference between the two forms of periodontitis being also significant. There was a posi- tive correlation between the levels of Synergistetes cluster A in saliva and all full mouth clinical periodontal parameters. Nevertheless, Synergistetes cluster B bac- teria and J. anthropi species were detected infrequently and at low levels in all the three subject groups. Conclusion: Synergistetes cluster A, but not cluster B, bacteria are found at higher prevalence, numbers and proportions in saliva from patients with peri- odontitis, than non-periodontitis subjects. These findings support the association of this cluster with periodontitis. G. N. Belibasakis 1 , V.- € O. € Ozt€ urk 2,3 , G. Emingil 3 , N. Bostanci 2 1 Oral Microbiology and Immunology, Institute of Oral Biology, Center of Dental Medicine, University of Z€ urich, Z€ urich, Switzerland, 2 Oral Translational Research, Institute of Oral Biology, Center of Dental Medicine, University of Z€ urich, Z€ urich, Switzerland and 3 Department of Periodontology, School of Dentistry, Ege University, _ Izmir, Turkey Georgios N. Belibasakis, DDS, MSc, PhD, Oral Microbiology and Immunology, Institute of Oral Biology, Center of Dental Medicine, University of Z€ urich, Plattenstrasse 11, Z€ urich 8032, Switzerland Tel: +41-44-634-3306 Fax: +41-44-634-4310 e-mail: george.belibasakis@zzm.uzh.ch Key words: fluorescent in situ hybridization; periodontitis; saliva; Synergistetes Accepted for publication January 15, 2013 Synergistetes is a recently identified bacterial phylum consisting of gram- negative anaerobes (1). Morphologi- cally they have been identified by fluo- rescent in situ hybridization (FISH) as long curved bacilli (2,3). They are dis- tributed in multiple anaerobic environ- ments (4), also found as part of the human microbiota in health and disease (5–7). Synergistetes comprises one of the 13 different phyla identified in the Human Oral Microbiome J Periodontal Res 2013 All rights reserved © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd JOURNAL OF PERIODONTAL RESEARCH doi:10.1111/jre.12061