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Journal of Periodontology Oct 2017The microbiota colonizing dental implants has been said to be similar to the microbiome surrounding teeth. In the absence of inflammation, a biofilm with pathologic...
BACKGROUND
The microbiota colonizing dental implants has been said to be similar to the microbiome surrounding teeth. In the absence of inflammation, a biofilm with pathologic bacteria can cover implant surfaces exposed to the oral cavity, for example, due to a remodeling process. The aim of the present study is to identify microbiota surrounding exposed dental implants in patients with and without a history of periodontitis through a deep-sequencing approach.
METHODS
An experimental abutment with the same surface and structure as a commercially available dental implant was used. Bacterial DNA was isolated, and the 16S ribosomal RNA gene was amplified and sequenced. Multiplexed tag-encoded sequencing of DNA from the samples was performed, and the reads were processed by metagenomic rapid annotation.
RESULTS
A wide variety of bacteria, 96 species, were identified. The most frequently found bacteria were Fusobacterium nucleatum and Prevotella denticola. Some species generally associated with periodontitis were found to a greater extent in patients without a history of periodontitis. Some bacteria that have never been described as part of the oral microbiome were identified in the present sample.
CONCLUSIONS
Analysis of data suggests that the bacteria surrounding exposed dental implants form a diverse microbiome regardless of the periodontal profile of patients. Further research is needed to clarify the role of these microorganisms in the oral environment.
Topics: Aged; Aged, 80 and over; Bacteria; Biofilms; DNA, Bacterial; Dental Abutments; Dental Implants; Female; Humans; Implants, Experimental; Male; Microbiota; Middle Aged; Periodontitis; RNA, Ribosomal, 16S
PubMed: 28492362
DOI: 10.1902/jop.2017.170051 -
Frontiers in Cellular and Infection... 2014Culture-independent analyses have greatly expanded knowledge regarding the composition of complex bacterial communities including those associated with oral diseases. A...
Comparison of bacterial culture and 16S rRNA community profiling by clonal analysis and pyrosequencing for the characterization of the dentine caries-associated microbiome.
Culture-independent analyses have greatly expanded knowledge regarding the composition of complex bacterial communities including those associated with oral diseases. A consistent finding from such studies, however, has been the under-reporting of members of the phylum Actinobacteria. In this study, five pairs of broad range primers targeting 16S rRNA genes were used in clonal analysis of 6 samples collected from tooth lesions involving dentine in subjects with active caries. Samples were also subjected to cultural analysis and pyrosequencing by means of the 454 platform. A diverse bacterial community of 229 species-level taxa was revealed by culture and clonal analysis, dominated by representatives of the genera Prevotella, Lactobacillus, Selenomonas, and Streptococcus. The five most abundant species were: Lactobacillus gasseri, Prevotella denticola, Alloprevotella tannerae, S. mutans and Streptococcus sp. HOT 070, which together made up 31.6 % of the sequences. Two samples were dominated by lactobacilli, while the remaining samples had low numbers of lactobacilli but significantly higher numbers of Prevotella species. The different primer pairs produced broadly similar data but proportions of the phylum Bacteroidetes were significantly higher when primer 1387R was used. All of the primer sets underestimated the proportion of Actinobacteria compared to culture. Pyrosequencing analysis of the samples was performed to a depth of sequencing of 4293 sequences per sample which were identified to 264 species-level taxa, and resulted in significantly higher coverage estimates than the clonal analysis. Pyrosequencing, however, also underestimated the relative abundance of Actinobacteria compared to culture.
Topics: Adult; Dental Caries; Dentin; Female; Humans; Male; Metagenome; Microbiota; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Streptococcus; Young Adult
PubMed: 25429361
DOI: 10.3389/fcimb.2014.00164 -
PloS One 2014Immunological processes in the etiopathogenesis of periodontitis, especially the aggressive form, are not well understood. This study examined clinical as well as...
OBJECTIVE
Immunological processes in the etiopathogenesis of periodontitis, especially the aggressive form, are not well understood. This study examined clinical as well as systemic immunological and local microbiological features in healthy controls and patients with different forms of periodontitis.
MATERIALS AND METHODS
14 healthy subjects, 15 patients diagnosed with aggressive periodontitis, and 11 patients with chronic periodontitis were recruited. Periodontal examination was performed and peripheral blood was collected from each patient. Lymphocyte populations as well as the release of cytokines by T-helper cells were determined by flow cytometry and enzyme linked immunosorbent spot assay. Subgingival plaque samples were taken from each individual and immediately cultivated for microbiological examination.
RESULTS
When stimulating peripheral blood mononuclear cells (PBMCs) with lipopolysaccharide, a higher IL-1β release was found in patients with moderate chronic periodontitis compared to the other groups (p<0.01). Numbers of B-cells, naïve and transitional B-cells, memory B-cells, and switched memory B-cells were within the reference range for all groups, but patients with chronic periodontitis showed the highest percentage of memory B-cells without class switch (p = 0.01). The subgingival plaque differed quantitatively as well as qualitatively with a higher number of Gram-negative anaerobic species in periodontitis patients. Prevotella denticola was found more often in patients with aggressive periodontitis (p<0.001) but did not show an association to any of the systemic immunological findings. Porphyromonas gingivalis, which was only found in patients with moderate chronic periodontitis, seems to be associated with an activation of the systemic immune response.
CONCLUSION
Differences between aggressive periodontitis and moderate chronic periodontitis are evident, which raises the question of an inadequate balance between systemic immune response and bacterial infection in aggressive periodontitis.
Topics: Adult; B-Lymphocytes; Bacteroidaceae Infections; Case-Control Studies; Chronic Periodontitis; Female; Humans; Interleukin-1beta; Male; Middle Aged; Porphyromonas gingivalis; Precursor Cells, B-Lymphoid; Prevotella; T-Lymphocytes, Helper-Inducer; Young Adult
PubMed: 25299619
DOI: 10.1371/journal.pone.0109187 -
Journal of Clinical Periodontology Nov 2014To determine microbial profiles that discriminate periodontal health from different forms of periodontal diseases. (Observational Study)
Observational Study
AIM
To determine microbial profiles that discriminate periodontal health from different forms of periodontal diseases.
METHODS
Subgingival biofilm was obtained from patients with periodontal health (27), gingivitis (11), chronic periodontitis (35) and aggressive periodontitis (24), and analysed for the presence of >250 species/phylotypes using HOMIM. Microbial differences among groups were examined by Mann-Whitney U-test. Regression analyses were performed to determine microbial risk indicators of disease.
RESULTS
Putative and potential new periodontal pathogens were more prevalent in subjects with periodontal diseases than periodontal health. Detection of Porphyromonas endodontalis/Porphyromonas spp. (OR 9.5 [1.2-73.1]) and Tannerella forsythia (OR 38.2 [3.2-450.6]), and absence of Neisseria polysaccharea (OR 0.004 [0-0.15]) and Prevotella denticola (OR 0.014 [0-0.49], p < 0.05) were risk indicators of periodontal disease. Presence of Aggregatibacter actinomycetemcomitans (OR 29.4 [3.4-176.5]), Cardiobacterium hominis (OR 14.9 [2.3-98.7]), Peptostreptococcaceae sp. (OR 35.9 [2.7-483.9]), P. alactolyticus (OR 31.3 [2.1-477.2]), and absence of Fretibacterium spp. (OR 0.024 [0.002-0.357]), Fusobacterium naviforme/Fusobacterium nucleatum ss vincentii (OR 0.015 [0.001-0.223]), Granulicatella adiacens/Granulicatella elegans (OR 0.013 [0.001-0.233], p < 0.05) were associated with aggressive periodontitis.
CONCLUSION
There were specific microbial signatures of the subgingival biofilm that were able to distinguish between microbiomes of periodontal health and diseases. Such profiles may be used to establish risk of disease.
Topics: Adult; Aggregatibacter actinomycetemcomitans; Aggressive Periodontitis; Bacteria; Bacteroides; Biofilms; Cardiobacterium; Carnobacteriaceae; Chronic Periodontitis; Female; Fusobacterium; Fusobacterium nucleatum; Gingivitis; Humans; Male; Microbiota; Neisseria; Peptostreptococcus; Periodontal Attachment Loss; Periodontal Index; Periodontal Pocket; Periodontium; Porphyromonas; Porphyromonas endodontalis; Prevotella; Young Adult
PubMed: 25139407
DOI: 10.1111/jcpe.12302