Carina Maciel Silva-Boghossian

Association of red complex, A. actinomycetemcomitans and non-oral bacteria with periodontal diseases

OBJECTIVE Pathogens related to systemic infections have been detected in the periodontal microbiota. The relationship amongst these pathogens, periodontal bacteria and periodontal clinical status is poorly understood. This study evaluated the association amongst red complex, A. actinomycetemcomitans (A.a) and non-oral pathogenic bacteria in subjects with good periodontal health (PH), gingivitis (G), chronic (CP) and aggressive (AP) periodontitis. METHODS Subgingival biofilm samples were obtained from 51 PH, 42 G, 219 CP and 90 AP subjects. The presence and levels of A.a, red complex (Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola), Acinetobacter baumannii, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, and Staphylococcus aureus were determined by DNA probes and DNA-DNA hybridization technique. RESULTS CP and AP subjects presented significantly higher prevalence and levels of A.a, red complex and A. baumannii than G and PH individuals (p<0.01), whereas S. aureus was detected in lower frequency and counts in AP as compared to the other groups (p<0.001). The predictor variables age, prevalence of red complex, and the presence of A. baumannii and P. aeruginosa were strongly associated with the frequency of sites with PD and CAL ≥5 mm. Increasing age (OR 1.08), high frequency of red complex (OR 6.10), and the presence of A.a with P. aeruginosa (OR 1.90) were associated with periodontal disease (p<0.001). Subjects harbouring a high prevalence of A.a, A. baumannii, and red complex with P. aeruginosa were more likely to have AP than CP (p<0.001). CONCLUSION Putative periodontal pathogens and non-oral bacteria alone or in association were strongly associated with periodontitis.

Microbial signature profiles of periodontally healthy and diseased patients

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.

Subgingival microbial profiles of generalized aggressive and chronic periodontal diseases

OBJECTIVE The aim of this study was to distinguish between generalized aggressive (GAgP) and chronic periodontitis (CP) based on the subgingival microbial profiles predominant in these diseases. METHODS Two-hundred and sixty subjects, 75 with GAgP and 185 with CP were recruited. Full-mouth clinical measurements were recorded. Individual subgingival plaque samples were taken from 7 sites per subject and analyzed for the prevalence and levels of 51 species by chequerboard. Differences between groups were examined by the Mann-Whitney test. Associations between bacterial species and GAgP were examined by logistic regression analysis. RESULTS Actinomyces gerensceriae, Actinomyces israelli, Eubacterium nodatum and Propionibacterium acnes were detected in significantly greater counts in GAgP, whereas Capnocytophaga ochracea, Fusobacterium periodonticum, Staphylococcus aureus and Veillonella parvula were more predominant in CP patients (adjusted p < 0.001). E. nodatum (at mean levels ≥4 × 10(5)) increased significantly the probability of a subject being diagnosed with GAgP than CP (OR 2.44 [0.96-6.20]), whereas P. gingivalis (OR 0.34 [0.11-0.93]) and T. denticola (OR 0.35 [0.11-0.94]) were associated with CP. CONCLUSIONS Very few subgingival species differed in prevalence and/or levels between GAgP and CP in this sample population. In particular, E. nodatum was strongly related to GAgP, whereas P. gingivalis and T. denticola were associated with CP.

Quantitative proteomic analysis of gingival crevicular fluid in different periodontal conditions.

Aim To quantify the proteome composition of the GCF in periodontal health (HH) and in sites with different clinical conditions in chronic periodontitis (CP) subjects. Material and Methods 5 subjects with HH and 5 with CP were submitted to full-mouth periodontal examination, and GCF sampling. Sites in the CP group were classified and sampled as periodontitis (P, probing depth, PD>4 mm), gingivitis (G, PD≤3mm with bleeding on probing, BOP), and healthy sites (H, PD≤3mm without BOP). GCF proteins were subjected to liquid chromatography electrospray ionization mass spectrometry for identification, characterization and quantification. Results 230 proteins were identified; 145 proteins were detected in HH, 214 in P, 154 in G, and 133 in H. Four proteins were exclusively detected at HH, 43 proteins at P, 7 proteins at G, and 1 protein at H. Compared to HH group, 35 and 6 proteins were more abundant in P and G (p<0.001), respectively; and 4, 15 and 37 proteins were less abundant in P, G and H (p≤0.01), respectively. Conclusions There are marked differences in the GCF proteome according to disease profile. Comprehension of the role of the identified proteins in the etiopathogenesis of periodontal disease may lead to biomarkers definition.

Suppuration-Associated Bacteria in Patients With Chronic and Aggressive Periodontitis

BACKGROUND Suppuration (SUP) on probing may be an indication of active periodontal breakdown. The aim of the present study is to analyze which subgingival species are associated with SUP in patients with chronic (CP) and aggressive (AgP) periodontitis. METHODS A total of 156 patients with CP and 66 with AgP were submitted to full-mouth periodontal examination and subgingival biofilm sampling (14 sites/patient). The counts of 44 bacterial species were determined by checkerboard. Comparisons between groups and sites were analyzed by the Mann-Whitney and Wilcoxon tests, respectively. Associations between frequency of SUP and bacterial species were analyzed by the Spearman correlation coefficient. RESULTS The prevalence of SUP in patients with CP was 24.4%, and in patients with AgP it was 30.3%, and the percentage of SUP sites in the groups was 5.72% ± 1.06% and 6.96% ± 1.70%, respectively (P >0.05). SUP sites from patients with CP had significantly higher counts of Veillonella parvula, Dialister pneumosintes, Tannerella forsythia, and Prevotella nigrescens than SUP sites from patients with AgP (P <0.005). Significant positive correlations between high frequency of SUP and high levels of Actinomyces spp, Streptococcus spp., members of the orange complex, Acinetobacter baumannii, and Pseudomonas aeruginosa were observed in patients with CP (P <0.05). In patients with AgP, Actinomyces oris, Propionibacterium acnes, P. aeruginosa, Staphylococcus aureus, and Streptococcus sanguinis were positively associated with SUP, whereas Prevotella intermedia presented a negative association with SUP (P <0.05). CONCLUSIONS SUP sites from patients with CP harbored significantly higher counts of several periodontal species than SUP sites from patients with AgP. Actinomyces spp., Streptococcus spp., members of the orange complex, T. forsythia, and certain non-oral pathogens were associated with a high number of sites with SUP.

Periodontal Status, Sociodemographic, and Behavioral Indicators in Subjects Attending a Public Dental School in Brazil: Analysis of Clinical Attachment Loss

BACKGROUND The purpose of this study was to assess the prevalence, extent, and severity of clinical attachment loss (AL) and their association with sociodemographic and behavioral parameters of subjects attending a public dental school in Brazil. METHODS A total of 491 consenting participants (21 to 70 years of age) submitted to a full-mouth periodontal clinical examination, assessment of missing teeth, and anamnesis questionnaires. The data were analyzed by multivariable models using logistic regression analyses. The dependent variables were moderate (> or =5 mm) and severe (> or =7 mm) clinical AL. RESULTS The prevalence of individuals with at least one site with clinical AL > or =5 or > or =7 mm was 72.1% and 60.9%, respectively. The mean clinical AL ranged from 2.9 to 3.9 mm, according to age. The mean frequency of sites with moderate (5 to 6 mm) and severe (> or =7 mm) clinical AL was 15.8% and 9.1%, respectively. Multivariate analyses identified smoking (odds ratio [OR] = 8.93), bleeding on probing (BOP) in >10% of sites (OR = 6.82 to 22.53), and > or =4 missing teeth (OR = 2.52) as risk indicators for clinical AL > or =5 mm in > or =10% of sites, whereas an age of 36 to 50 years (OR = 1.72), smoking (OR = 7.66), and BOP in >10% of sites (OR = 6.84 to 24.89) were considered risk indicators for clinical AL > or =7 mm in at least one site. CONCLUSIONS This particular Brazilian population presented a high prevalence and extent of severe periodontal disease. Age, smoking, and BOP were risk indicators associated with moderate and severe AL in this population.

Prevalence of Pseudomonas aeruginosa and Acinetobacter spp. in subgingival biofilm and saliva of subjects with chronic periodontal infection

P. aeruginosa and Acinetobacter spp. are important pathogens associated with late nosocomial pneumonia in hospitalized and institutionalized individuals. The oral cavity may be a major source of these respiratory pathogens, particularly in the presence of poor oral hygiene and periodontal infection. This study investigated the prevalence of P. aeruginosa and Acinetobacter spp. in subgingival biofilm and saliva of subjects with periodontal disease or health. Samples were obtained from 55 periodontally healthy (PH) and 169 chronic periodontitis (CP) patients. DNA was obtained from the samples and detection of P. aeruginosa and Acinetobacter spp. was carried out by multiplex and nested PCR. P. aeruginosa and Acinetobacter spp. were detected in 40% and 45% of all samples, respectively. No significant differences in the distribution of these microorganisms between men and women, subgingival biofilm and saliva samples, patients ≤ 35 and > 35 years of age, and smokers and non-smokers were observed regardless periodontal status (p > 0.05). In contrast, the frequencies of P. aeruginosa and Acinetobacter spp. in saliva and biofilm samples were significantly greater in CP than PH patients (p < 0.01). Smokers presenting P. aeruginosa and high frequencies of supragingival plaque were more likely to present CP than PH. P. aeruginosa and Acinetobacter spp. are frequently detected in the oral microbiota of CP. Poor oral hygiene, smoking and the presence of P. aeruginosa are strongly associated with periodontitis.

Salivary microbiota of HIV‐positive children and its correlation with HIV status, oral diseases, and total secretory IgA

AIM This study aimed to investigate the prevalence and levels of salivary microorganisms in HIV-positive children, and their correlation to HIV status, oral lesions, and salivary IgA levels. DESIGN Forty-two HIV-positive and 36 control children were clinically examined, had their saliva collected and processed for the microbiological analysis of 38 bacterial taxa by the checkerboard method, and salivary IgA quantification by ELISA. RESULTS The majority of the species tested were more prevalent in control children than in the HIV group. Mean concentration of total salivary IgA was similar in both groups. High levels of Veillonella parvula were found in children with cheilitis and herpes. Tannerella forsythia, Eikenella Corrodens, and Propionibacterium acnes were prevalent in children with gingivitis, while Fusobacterium periodonticum, Streptococcus gordonii, and Streptococcus oralis were significantly more frequent in children with no oral lesions. Significant negative correlations between salivary IgA levels and Eubacterium nodatum and oral streptococci were observed (P < 0.05). CONCLUSION HIV-seropositive children presented significantly lower prevalence and levels of several bacterial species in saliva; HIV-positive children are able to mount a mucosal immune response; HIV-seropositive children under highly active antiretroviral therapy presented low prevalence of oral lesions.

Adsorption of chlorhexidine on synthetic hydroxyapatite and in vitro biological activity

The kinetic of chlorhexidine digluconate (CHXDG) uptake from aqueous solution by hydroxyapatite (HA) was investigated by ultraviolet (UV) analysis performed in HA powder (UV-solid) after the CHX adsorption. Adsorption isotherm of chlorhexidine (CHX) uptake was modeled by a combination of Languimir and Langmuir-Freundlich mechanisms. Strong molecule-molecule interactions and positive cooperativity predominated in the surface when CHX concentration was above 8.6 μg(CHX)/mg(HA). UV-solid spectra (shape, intensity and band position) of CHX bound to HA revealed that long-range molecular structures, such as aggregates or micelles, started to be formed at low CHX concentrations (1.52 μg(CHX)/mg(HA)) and predominated at high concentrations. Grazing-incidence X-ray diffraction (GIXRD) analysis from synchrotron radiation discarded the formation of crystalline structures on HA surface or precipitation of CHX crystalline salts, as suggested in previous works. The effect of the HA/CHX association on HA in vitro bioactivity, cytotoxicity and CHX antimicrobial activity was evaluated. It was shown that CHX did not inhibit the precipitation of a poorly crystalline apatite at HA/CHX surface after soaking in simulating body fluid (SBF). Cell viability studies after exposure to extracts of HA and HA/CHX showed that both biomaterials did not present significant in vitro toxicity. Moreover, HA/CHX inhibited Enterococcus faecalis growth for up to 6 days, revealing that binding to HA did not affect antimicrobial activity of CHX and reduced bacterial adhesion. These results suggested that HA/CHX association could result in a potential adjuvant antimicrobial system for clinical use.

S-Nitrosoglutathione Accelerates Recovery from 5-Fluorouracil-Induced Oral Mucositis

Introduction Mucositis induced by anti-neoplastic drugs is an important, dose-limiting and costly side-effect of cancer therapy. Aim To evaluate the effect of the topical application of S-nitrosoglutathione (GSNO), a nitric oxide donor, on 5-fluorouracil (5-FU)-induced oral mucositis in hamsters. Materials and Methods Oral mucositis was induced in male hamsters by two intraperitoneal administrations of 5-FU on the first and second days of the experiment (60 and 40 mg/kg, respectively) followed by mechanical trauma on the fourth day. Animals received saline, HPMC or HPMC/GSNO (0.1, 0.5 or 2.0 mM) 1 h prior to the 5-FU injection and twice a day for 10 or 14 days. Samples of cheek pouches were harvested for: histopathological analysis, TNF-α and IL-1β levels, immunohistochemical staining for iNOS, TNF-α, IL-1β, Ki67 and TGF-β RII and a TUNEL assay. The presence and levels of 39 bacterial taxa were analyzed using the Checkerboard DNA-DNA hybridization method. The profiles of NO released from the HPMC/GSNO formulations were characterized using chemiluminescence. Results The HPMC/GSNO formulations were found to provide sustained release of NO for more than 4 h at concentration-dependent rates of 14 to 80 nmol/mL/h. Treatment with HPMC/GSNO (0.5 mM) significantly reduced mucosal damage, inflammatory alterations and cell death associated with 5-FU-induced oral mucositis on day 14 but not on day 10. HPMC/GSNO administration also reversed the inhibitory effect of 5-FU on cell proliferation on day 14. In addition, we observed that the chemotherapy significantly increased the levels and/or prevalence of several bacterial species. Conclusion Topical HPMC/GSNO accelerates mucosal recovery, reduces inflammatory parameters, speeds up re-epithelization and decreases levels of periodontopathic species in mucosal ulcers.