Clinical association of Spirochaetes and Synergistetes with peri-implantitis.
OBJECTIVE
The microbial composition of peri-implantitis-associated biofilms may resemble that of periodontitis, with some distinctive differences, as identified by various conventional or molecular detection methods. Yet, the complete microbiome of peri-implantitis awaits further characterization. The present clinical study was undertaken with the aim to investigate the association of Spirochaetes, and the more recently identified phylum Synergistetes, with peri-implantitis.


METHODS
Submucosal biofilms were obtained from single sites of patients with peri-implantitis (n = 43) or individuals with peri-implant health (n = 41). The samples were analysed by fluorescence in situ hybridization (FISH) and epifluorescence microscopy, using 16S rRNA-based oligonucleotide probes for Synergistetes cluster A, subclusters A1 and A2, and Treponema groups I-III and IV.


RESULTS
Treponema group IV was barely detectable, whereas Treponema groups I-III were detected at low prevalence in health, but their prevalence and numbers were significantly increased in peri-implantitis by 48% and 2.4-log, respectively. Synergistetes cluster A was detected in half of the healthy sites, and its prevalence and numbers were significantly increased in peri-implantitis by 30% and 2.5-log, respectively. No quantitative differences were found between Synergistetes subclusters A1 and A2 numbers, as both increased by 2.8-log. Synergistetes cluster A displayed strong correlations with several clinical peri-implant parameters, but Treponema groups I-III only with probing pocket depth.


CONCLUSIONS
The present clinical cross-sectional study demonstrates that Spriochaetes of the Treponema groups I-III, but not group IV, and Synergistetes of the cluster A are highly associated with peri-implantitis. Synergistetes cluster A appears to display a stronger association with peri-implantitis than Spirochaetes.
Section of Oral Microbiology and Immunology, Institute of Oral Biology, Center of Dental Medicine, University of Zürich, Zürich, Switzerland.
Georgios N
GN
Belibasakis
Department of Oral Surgery and Implantology, Faculty of Dentistry, University of Barcelona, Barcelona, Spain.
Javier
J
Mir-Mari
Clinic of Preventive Dentistry, Periodontology and Cariology, Center of Dental Medicine, University of Zürich, Zürich, Switzerland.
Philipp
P
Sahrmann
Section of Periodontology, Faculty of Odontology, University Complutense, Madrid, Spain.
Ignacio
I
Sanz-Martin
Clinic of Preventive Dentistry, Periodontology and Cariology, Center of Dental Medicine, University of Zürich, Zürich, Switzerland.
Patrick R
PR
Schmidlin
Clinic of Fixed and Removable Prosthodontics and Dental Material Science, Center of Dental Medicine, University of Zürich, Zürich, Switzerland.
Ronald E
RE
Jung
D018441:Biofilms; D003430:Cross-Sectional Studies; D005260:Female; D006089:Gram-Negative Anaerobic Bacteria / Q000302:isolation & purification*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008856:Microscopy, Fluorescence; D008875:Middle Aged; D057873:Peri-Implantitis / Q000382:microbiology*; D013144:Spirochaetales / Q000302:isolation & purification*
Spirochaetes; Synergistetes; dental implants; fluorescence in situ hybridization; microbiology; peri-implantitis