Periodontal-disease-associated biofilm: A reservoir for pathogens of medical importance.

The ecological diversity of the periodontal microenvironment may provide suitable conditions for the colonization of species not usually considered members of the oral microbiota. In this investigation, we aimed to determine the prevalence and levels of pathogenic species of medical relevance in the microbiota of individuals with distinct periodontal clinical status. Subgingival biofilm was obtained from patients with periodontal health (H, n = 81), gingivitis (G, n = 55), generalized aggressive (AgP, n = 36) or chronic periodontitis (CP, n = 98), and analyzed for 39 microbial taxa using a checkerboard DNA-DNA hybridization technique. Microbial differences among groups, as well as associations between clinical and microbiological parameters were sought by non-parametric and univariate correlation tests. Neisseria spp., Peptostreptococus anaerobius, Candida albicans, enterobacteria, Pseudomonas aeruginosa, Eubacterium saphenum, Clostridium difficile and Olsenella uli were detected in high mean prevalence and counts in the subgingival microbiota of the study population. Species that were more related to periodontal inflammation and tissue destruction at the patient and site levels included enterobacteria, C. albicans, Neisseria spp., P. aeruginosa, O. uli, Hafnia alvei, Serratia marcescens and Filifactor alocis (p < 0.05). In contrast, Fusobacterium necrophorum, Lactobacillus acidophilus, Staphylococcus aureus and Streptococcus pneumoniae were associated with periodontal health (p < 0.05). Pathogenic species of medical importance may be detected in high prevalence and levels in the periodontal microbiota. Regardless of their role in periodontal health or disease, the periodontal biofilm may be a source for dissemination and development of systemic infections by these pathogenic microorganisms.

Proteomic analysis of whole saliva in chronic periodontitis.

Periodontitis is a chronic inflammatory disease resulting from a dysbiosis of the dental biofilm and a dysregulated host response in susceptible individuals. It is characterized by periodontal attachment destruction, bone resorption and eventual tooth loss. Salivary biomarkers have been sought to predict and prevent periodontitis. This comparative study analyzed the salivary proteome of individuals with chronic periodontitis (CP) and periodontal health (PH) and correlated specific proteins with clinical parameters of disease by using mass spectrometry. Stimulated whole saliva was obtained 10 PH and 30 CP patients and pooled into 5 healthy control samples and 15 CP samples. After precipitation with TCA, samples were digested enzymatically with trypsin and analyzed by a LTQ Orbitrap Velos equipped with a nanoelectrospray ion source. A wide range of salivary proteins of various functions was significantly reduced in CP individuals, whereas salivary acidic proline-rich phosphoprotein, submaxillary gland androgen-regulated protein, histatin-1, fatty acid binding protein, thioredoxin and cystatin-SA were predominant in diseased patients and correlated significantly with signs of periodontal attachment loss and inflammation. In conclusion, few specific salivary proteins were associated with CP. These findings may contribute to the identification of disease indicators or signatures for the improvement of periodontal diagnosis. SIGNIFICANCE: Periodontitis is a chronic inflammatory disease that results in periodontal attachment destruction, bone resorption and eventual tooth loss. Salivary biomarkers have been sought to predict periodontitis. The analysis of the salivary proteome of individuals with chronic periodontitis indicated that several proteins of various functions were significantly reduced in these individuals, except for salivary acidic proline-rich phosphoprotein, submaxillary gland androgen-regulated protein, histatin, fatty acid binding protein, thioredoxin and cystatin. Differences in salivary proteome profiles between periodontal health and periodontitis may contribute to the identification of disease indicators and to the improvement of periodontal diagnosis and treatment.

The effect of supragingival biofilm re-development on the subgingival microbiota in chronic periodontitis.

OBJECTIVE: In this study, we hypothesized that in the absence of oral hygiene, re-growth of the climax microbial communities of supra and subgingival biofilm happens in a faster and more intense fashion in individuals with chronic periodontitis (CP) compared to periodontally healthy controls (PH). DESIGN: Thirty patients (PH=15 and CP=15) received professional supragingival prophylaxis, and were asked to refrain from oral hygiene for 7days. Supra and subgingival biofilm samples and GCF were collected from randomly selected quadrants at baseline (before prophylaxis), immediately after prophylaxis, 2h, 6h, 24h, and 7days after prophylaxis. The composition of the biofilm was determined by the checkerboard method. RESULTS: All subjects developed gingivitis at the end of 7days without oral hygiene. GCF mean volumes were significantly higher in CP than PH patients at baseline, but they started decreasing 2h after prophylaxis, returning to baseline levels after 24h in both groups. Significant increases in mean counts for most of the species evaluated were observed in both groups and biofilms over time (p<0.05). Few hours after prophylaxis, a more marked reduction in microbial counts happened in the supragingival biofilm of the CP group, and re-development of biofilm started later than in the PH group. At 7days, no differences were seen between groups. Significant differences in kinetics of re-colonization between groups were observed only in the subgingival biofilm for T. denticola and F. nucleatum ss vicentii (increased in the CP), and N. mucosa (increased in the PH group; p<0.05). CONCLUSIONS: Biofilm re-development was very similar between CP and PH individuals, although microbial re-growth occurred few hours earlier in PH than PC. Only 3 species in the subgingival biofilm differed in re-colonization between groups. Thus, we reject the hypothesis that re-colonization of biofilm in CP patients is more intense and faster than in individuals with PH.