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Introduction Biofilms protect bacteria from antibiotics and this can produce drug-resistant strains, especially the main pathogen of periodontitis, Porphyromonas gingivalis. Carbon quantum dots with various biomedical properties are considered to have great application potential in antibacterial and anti-biofilm treatment. Methods Tinidazole carbon quantum dots (TCDs) and metronidazole carbon quantum dots (MCDs) were prepared by a hydrothermal method with the clinical antibacterial drugs tinidazole and metronidazole, respectively. Then, TCDs and MCDs were characterized by transmission electron microscopy, UV-visible spectroscopy, infrared spectroscopy and energy-dispersive spectrometry. The antibacterial effects were also investigated under different conditions. Results The TCDs and MCDs had uniform sizes. The results of UV-visible and energy-dispersive spectrometry confirmed their important carbon polymerization structures and the activity of the nitro group, which had an evident inhibitory effect on P. gingivalis, but almost no effect on other bacteria, including Escherichia coli, Staphylococcus aureus and Prevotella nigrescens. Importantly, the TCDs could penetrate the biofilms to further effectively inhibit the growth of P. gingivalis under the biofilms. Furthermore, it was found that the antibacterial effect of TCDs lies in its ability to impair toxicity by inhibiting the major virulence factors and related genes involved in the biofilm formation of P. gingivalis, thus affecting the self-assembly of biofilm-related proteins. Conclusion The findings demonstrate a promising new method for improving the efficiency of periodontitis treatment by penetrating the P. gingivalis biofilm with preparations of nano-level antibacterial drugs.

Исследованы биофармацевтические свойства модельных гелевых композиций c экстрактом корня барбариса и использованием в качестве гелеобразователей метилцеллюлозы, натриевой соли карбоксиметилцеллюлозы, натриевой соли альгиновой кислоты и поливинилового спирта методами прямой диффузии в агаровый гель и диализа через полупроницаемую мембрану. Определены кинетические закономерности процесса и скорости набухания исследуемых гелевых основ. Показана целесообразность использования натриевой соли альгиновой кислоты для получения стоматологического геля с экстрактом корня барбариса, обладающего специфической бактериостатической активностью в отношении таких пародонтопатогенных микроорганизмов, как Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens и Actinobacillus actinomycetemcomitans, для профилактики и лечения воспалительных заболеваний пародонта.

The beneficial effects of Sr- and Mg-doped hydroxyapatite (HAp) on osteoblast proliferation and bone regeneration have been investigated in the past, and the antibacterial ability of Zn ions is well known. However, HAp coatings doped with these three elements via thermal spraying have not yet been investigated. In this study, HAp powder was synthesized at different pH values (4, 6, 8, and 10) and calcined at different temperatures (200, 400, 600, 800, and 1000 °C) to obtain HAp with the highest purity. Subsequently, strontium-, magnesium-, and zinc-doped HAp powders were synthesized at the optimal pH value and calcination temperature. The HAp powder was then coated onto Ti disks using atmospheric plasma spraying (APS) or vapor-induced pore-forming atmospheric plasma spraying (VIPF-APS) techniques at different working currents (350, 400, and 450 A) and spraying distances (10 and 15 cm). X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy equipped with energy-dispersive spectroscopy were used for material characterization to determine the optimal parameters. With these optimal coating parameters, HAp, Zn-HAp, SrMg-HAp, and ZnSrMg-HAp powders were deposited onto the Ti disks using VIPF-APS and named HAp-Ti, Zn-HAp-Ti, SrMg-HAp-Ti, and ZnSrMg-HAp-Ti, respectively. The in vitro bioactivity of these four groups was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and alkaline phosphatase (ALPase) activity assay. Besides, the antibacterial activities against

Information about bacterial diversity, such as the number of each species in the root canals of primary teeth, contributes to improving our effective management of infections of endodontic origin in primary teeth. This study made a qualitative and quantitative assessment of the bacteria in the root canals of primary teeth with necrotic pulp, using the fluorescence in situ hybridization (FISH) technique. Thirty-one primary teeth with pulp necrosis from 31 children were evaluated using the FISH technique, to detect the presence and density of Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Enterococcus faecalis, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Streptococcus, Streptococcus mutans, Streptococcus sobrinus, Tannerella forsythia and Treponema denticola. Descriptive measures explained the data related to density, and Student’s t-test assessed the differences among the densities of each bacterium, according to signs and symptoms. The bacterial density was paired and correlated. All bacteria tested were detected and identified in all the samples. The average number of bacterial individuals from each species ranged from 1.9 x 108 cells/mL (S. mutans) to 3.1 x 108 cells/mL (F. nucleatum) (p > 0.05). The sum of the mean counts of each bacterium represented almost 80% of the entire microbial community. Patients with pain had significantly more T. denticola, and those with edema showed a greater density of Streptococcus and P. nigrescens (p < 0.05). This study revealed that all 12 bacteria evaluated were found in all primary teeth with pulp necrosis. There was no predominance among the species studied; all species had a similar number of individuals.

To assess the influence of periodontal disease on cerebral hemorrhage and its clinical course, we examined the association of the serum IgG titer of periodontal pathogens with hemorrhage growth and 3-month outcome. We consecutively enrolled 115 patients with acute cerebral hemorrhage (44 females, aged 71.3 ± 13.1 years) and used ELISA to evaluate the serum IgG titers of 9 periodontal pathogens: Porphyromonas gingivalis, Aggregatibacter (A.) actinomycetemcomitans, Prevotella intermedia, Prevotella nigrescens, Fusobacterium (F.) nucleatum, Treponema denticola, Tannerella forsythensis, Campylobacter rectus, and Eikenella corrodens. Significant hematoma growth was defined as an increase in the volume of >33% or an absolute increase in the volume of >12.5 mL. A poor outcome was defined as a 3 or higher on the modified Rankin Scale. We observed hemorrhage growth in 13 patients (11.3%). Multivariate analysis revealed that increased IgG titers of A. actinomycetemcomitans independently predicted the elevated hemorrhage growth (odds ratio 5.26, 95% confidence interval 1.52-18.25, p = 0.01). Notably, augmented IgG titers of F. nucleatum but not A. actinomycetemcomitans led to a poorer 3-month outcome (odds ratio 7.86, 95% confidence interval 1.08-57.08, p = 0.04). Thus, we demonstrate that elevated serum IgG titers of A. actinomycetemcomitans are an independent factor for predicting cerebral hemorrhage growth and that high serum IgG titers of F. nucleatum may predict a poor outcome in patients with this disease. Together, these novel data reveal how systemic periodontal pathogens may affect stroke patients, and, should, therefore, be taken into consideration in the management and treatment of these individuals.

Microbial agents including periodontal pathogens have recently appeared as important actors in Alzheimer's disease (AD) pathology. We examined associations of clinical periodontal and bacterial parameters with incident all-cause and AD dementia as well as AD mortality among US middle-aged and older adults. Clinical [Attachment Loss (AL); probing pocket depth (PPD)] and bacterial [pathogen immunoglobulin G (IgG)] periodontal markers were investigated in relation to AD and all-cause dementia incidence and to AD mortality, using data from the third National Health and Nutrition Examination Surveys (NHANES III, 1988-1994) linked longitudinally with National Death Index and Medicare data through January 1, 2014, with up to 26 years of follow-up. Sex- and age-specific multivariable-adjusted Cox proportional hazards models were conducted. Among those ≥65 years, AD incidence and mortality were consistently associated with PPD, two factors and one cluster comprised of IgG titers against Porphyromonas gingivalis (P. gingivalis), Prevotella melaninogenica (P. melaninogenica) and Campylobacter rectus (C. rectus) among others. Specifically, AD incidence was linked to a composite of C. rectus and P. gingivalis titers (per SD, aHR = 1.22; 95% CI, 1.04-1.43, p = 0.012), while AD mortality risk was increased with another composite (per SD, aHR = 1.46; 95% CI, 1.09-1.96, p = 0.017) loading highly on IgG for P. gingivalis, Prevotella intermedia, Prevotella nigrescens, Fusobacterium nucleatum, C. rectus, Streptococcus intermedius, Capnocylophaga Ochracea, and P. melaninogenica. This study provides evidence for an association between periodontal pathogens and AD, which was stronger for older adults. Effectiveness of periodontal pathogen treatment on reducing sequelae of neurodegeneration should be tested in randomized controlled trials.

Made available in DSpace on 2018-12-11T17:19:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-06-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Background: The aim of this study was to evaluate the effects of non-surgical periodontal therapies on smokers with chronic periodontitis, involving multiple adjunctive applications of antimicrobial photodynamic therapy (aPDT), and systemic metronidazole (MTZ) with amoxicillin (AMX). Methods: All participants were treated with scaling and root planing (SRP). Seventeen patients received 400 mg of MTZ and 500 mg of AMX three times per day for 7 days (MTZ + AMX). Additionally, 17 patients received a placebo, and 17 patients were treated with three applications of aPDT (immediately, 48 h and 96 h after SRP). Clinical and microbiological examinations were performed at baseline and at 90 and 180 days post-therapy. Subgingival samples were analyzed using real-time polymerase chain reaction. Results: After 180 days, the patients in groups MTZ + AMX and aPDT had significantly lower mean probing depths, more clinical attachment level gains and less bleeding on probing. At 180 days, in the moderate pocket there was a reduction in the levels of Porphyromonas gingivalis and Prevotella nigrescens in the MTZ + AMX group, while group aPDT showed a reduction in Prevotella nigrescens. Furthermore, at 180 days, in the deep pocket a reduction in Porphyromonas gingivalis, Prevotella intermedia and Prevotella nigrescens was observed in group MTZ + AMX, as well as a reduction in the levels of Prevotella intermedia and Prevotella nigrescens in group aPDT. Conclusion: In smokers with periodontitis, the MTZ + AMX and aPDT treatments significantly improved the effects of SRP. Department of Surgery and Integrated Clinic São Paulo State University (UNESP) Dentistry School of Araçatuba Department of Pediatric and Social Dentistry São Paulo State University (UNESP) Dentistry School of Araçatuba Department of Oral Diagnosis Dentistry School of Piracicaba UNICAMP Department of Surgery and Integrated Clinic São Paulo State University (UNESP) Dentistry School of Araçatuba Department of Pediatric and Social Dentistry São Paulo State University (UNESP) Dentistry School of Araçatuba

Various antimicrobial agents are widely used in the therapy of oral inflammatory diseases. However, their side effects and the appearance of drug resistance justify research on natural antimicrobial agents to target oral pathogens that are safe for the host. In the present study, antimicrobial properties of mastic extract on commensal and pathogenic oral bacteria, as well as its possible cytotoxic effect toward cells of epithelial and mesenchymal origin, were evaluated and compared with the common antimicrobial agents hydrogen peroxide (HOral and periodontal pathogens (Porphyromonas gingivalis, Streptococcus mutans [Sm], Streptococcus oralis, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Prevotella intermedia, and Prevotella nigrescens) were treated with different concentrations of mastic extract, 3% HMastic extract led to significantly (P ≤0.016) increased inhibition of the tested periodontal pathogens compared with HThe present data demonstrate mastic extract's inhibition of periodontal pathogens, as well as beneficial effects on cell viability, compared with H

Highlights • It is concluded that the feline oral flora is highly diverse than canine oral flora. • Porphyromonas gingivalis, Prevotella nigrescens and Porphyromonas gulae were the dominant species in cats and dogs. • T. forsythia, C. ochracea, and C. sputigena in cats and T. forsythia, C. ochracea, C. sputigena T. denticola and, E. corrodens, in dogs showed that the prevalence was lower than 10%. E. corrodens in cats and, P. intermedia, A. actinomycetemcomitans, and C. rectus in dogs were also isolated from the swab samples with less than 30% percentage. • A balanced diet for cats and dogs should be provided to reduce the formation of residues in the oral flora. Daily rinsing with antiseptic solutions may also be helpful against the development of periodontal pathogens., Periodontal disease is the most common infectious disease of cats and dogs which are strongly associated with periodontal pathogens. The primary etiologic factor in the formation of periodontal disease is microbial dental plaque accumulation on teeth. In our research, we aimed to investigate the presence of periodontal disease-related bacterial species in dental plaques of cats and dogs. Specimens collected from 50 cats and 51 dogs with periodontal disease examined in terms of periodontal pathogens by polymerase chain reaction (PCR) using primers directed to 16S rRNA and tdpA genes. Our findings indicate the presence of periodontal disease-related pathogens, especially Porphyromonas gingivalis (cats 96%, dogs 88%), Prevotella nigrescens (cats 90%, dogs 57%) and, Porphyromonas gulae (cats 70%, dogs 39%). In addition, the prevalence of Tannerella forthysia (cats 2%, dogs 4%) well-known pathogen in cats and dogs were isolated with an extremely low percentage. Furthermore, our results suggest that the feline oral cavity microbiota has considerably more diversity than dogs. Consequently, daily oral hygiene practices may become essential for controlling the pathogenic bacteria which have clinical importance and in preventing the propagation of microorganisms in the oral cavity of cats and dogs.

Made available in DSpace on 2019-10-06T16:07:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-03-01 Background: The aim of this study was to evaluate the effect of multiple sessions of antimicrobial photodynamic therapy (aPDT) on the treatment of experimental periodontitis (EP) in rats treated with chemotherapy. Methods: Chemotherapy using 5-fluorouracil (5-FU) consisted of intraperitoneal administration of 60 and 40 mg/kg of 5-FU. 120 rats were subjected to chemotherapy with 5-FU and divided into groups: PT (periodontal treatment); PT+1aPDT (PT and single aPDT session); PT+4aPDT(PT and 4 sessions of aPDT); 1aPDT (single aPDT session); 4aPDT(4 sessions of aPDT). EP was induced in the mandibular molars via ligature placement. The alveolar bone loss (ABL) area in the furcation region was analysed histometrically. Proliferating cell nuclear antigen (PCNA), tartrate-resistant acid phosphatase (TRAP), receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG) and cleaved caspase-3 (CC3) were analysed by immunohistochemistry. Prostaglandin E2 was quantified using an ELISA, tumor necrosis factor (TNF)-α and interleukin (IL)-6 were assessed using a multiplex method. The prevalence of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia and Fusobacterium nucleatum was assessed using PCR. The data were statistically analysed (P < 0.05). Results: The PT+4aPDT group showed lower ABL than the PT or 1aPDT groups on day 7. Rats treated with aPDT showed a higher number of PCNA-positive cells with reduced immunolabeling of RANKL. Significant reductions in Prevotella nigrescens were observed in the PT+4aPDT group and in Aggregatibacter actinomycetemcomitans for the 1aPDT and 4aPDT groups. Conclusion: Repeated sessions of aPDT as an adjunct or alternative therapy were effective at reducing ABL, regulating bone metabolism, and reducing Prevotella nigrescens and Aggregatibacter actinomycetemcomitans. São Paulo State University (Unesp) School of Dentistry Araçatuba Department of Surgery and Integrated Clinic - Division of Periodontics São Paulo State University (Unesp) School of Dentistry Araçatuba Department of Basic Science São Paulo State University (Unesp) School of Dentistry Araçatuba Department of Paediatric and Social Dentistry Liverpool John Moores University School of Pharmacy and Biomolecular Sciences São Paulo State University (Unesp) School of Dentistry Araçatuba Department of Surgery and Integrated Clinic - Division of Periodontics São Paulo State University (Unesp) School of Dentistry Araçatuba Department of Basic Science São Paulo State University (Unesp) School of Dentistry Araçatuba Department of Paediatric and Social Dentistry

Chronic periodontitis is the most prevalent form of inflammatory destructive bone disease and has been affecting humans since antiquity. Evidence suggest that genetic factors can highly influence periodontitis risk, modulating disease elements such as the susceptibility to microbial colonization and the nature of subsequent host-microbe interaction. Several single-nucleotide polymorphisms (SNPs) have been associated with the occurrence of periodontitis, but the full range of genetic influence in periodontitis outcomes remains to be determined. In this context, this study comprises an analysis of possible correlation between periodontitis-related genetic variants with changes in the subgingival microbiological pattern performed in a Brazilian population (n = 167, comprising 76 chronic periodontitis patients and 91 healthy subjects). For the genetic characterization, 19 candidate SNPs were selected based on the top hits of previous large genome wide association studies (GWAS), while the subgingival microbiota was characterized for the presence and relative quantity of 40 bacterial species by DNA-DNA checkerboard. The case/control association test did not demonstrate a significant effect of the target SNPs with the disease phenotype. The polymorphism rs2521634 proved significantly associated with Tannerella. forsythia, Actinomyces gerencseriae, Fusobacterium periodonticum, and Prevotella nigrescens; rs10010758 and rs6667202 were associated with increased counts of Porphyromonas gingivalis; and rs10043775 proved significantly associated with decreased counts of Prevotella intermedia. In conclusion, we present strong evidence supporting a direct connection between the host’s genetic profile, specifically rs2521634, rs10010758, rs6667202, and rs10043775 polymorphisms, and the occurrence of chronic periodontitis-associated bacteria.

This study investigated the presence of target bacterial species and the levels of endotoxins in teeth with apical periodontitis. Levels of inflammatory mediators (interleukin [IL]-1β and tumor necrosis factor [TNF]-α) were determined after macrophage stimulation with endodontic content after different phases of endodontic therapy using different irrigants.Thirty primarily infected root canals were randomly assigned into 3 groups according to the irrigant used for root canal preparation (n = 10 per group): GI: 2.5% sodium hypochlorite, GII: 2% chlorhexidine gel, and GIII (control group): saline solution. Root canal samples were taken by using paper points before (s1) and after root canal instrumentation (s2), subsequently to 17% EDTA (s3), after 30 days of intracanal medication (Ca[OH]2 + saline solution) (s4), and before root canal obturation (s5). Polymerase chain reaction (16S recombinant DNA) and limulus amebocyte lysate assay were used for bacterial and endotoxin detection, respectively. Macrophages were stimulated with the root canal contents for IL-1β/TNF-α measurement using enzyme-linked immunosorbent assay.Porphyromonas gingivalis (17/30), Porphyromonas endodontalis (15/30), and Prevotella nigrescens (11/30) were the most prevalent bacterial species. At s1, endotoxins were detected in 100% of the root canals (median = 32.43 EU/mL). In parallel, substantial amounts of IL-1β and TNF-α were produced by endodontic content-stimulated macrophages. At s2, a significant reduction in endotoxin levels was observed in all groups, with GI presenting the greatest reduction (P.05). After a root canal rinse with EDTA (s3), intracanal medication (s4), and before root canal obturation (s5), endotoxin levels reduced without differences between groups (P.05). IL-1β and TNF-α release decreased proportionally to the levels of residual endotoxin (P.05).Regardless of the use of sodium hypochlorite or CHX, the greatest endotoxin reduction occurs after chemomechanical preparation. Increasing steps of root canal therapy associated with intracanal medication enhances endotoxin reduction, leading to a progressively lower activation of proinflammatory cells such as macrophages.

Objective To date, no information on the distribution of periodontal microorganisms among family members of Chinese patients with aggressive peridontitis (AgP) is available. The aim of the present study was to investigate the probability of transmission of eight periodontal microorganisms between patients with aggressive periodontitis and their family members. Design Saliva and pooled subgingival plaque samples were collected from 103 participants from 41 nuclear families (including 41 AgP probands, 19 mothers, 22 fathers, 21 siblings). Eight periodontal microorganisms, including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Campylobacter rectus, Prevotella intermedia, Prevotella nigrescens and Fusobacterium nucleatum were detected in these samples by the polymerase chain reaction (PCR). In addition, the distribution of fimA genotypes was assessed in P. gingivalis-positive individuals by PCR. Results P. gingivalis, T. forsythia, T. denticola, C. rectus and F. nucleatum were the most frequently detected species both in AgP probands and in their relatives. Kappa statistical analysis revealed that the detection of A. actinomycetemcomitans (Kappa = 0.503) and F. nucleatum (Kappa = 0.565) in probands was highly consistent with that in their relatives. Most probands shared the identical fimA genotype of P. gingivalis with their relatives. Conclusions Our results suggested that the intrafamilial transmission of periodontal microorganisms may occur between Chinese patients with aggressive periodontitis and their relatives.

Background: This study investigates the association between detectable plasmatic human immunodeficiency virus (HIV) viral load (HVL) and high levels of periodontal- and non-periodontal-related microorganisms in the subgingival microbiota of individuals with HIV. Methods: Thirty-seven individuals with HIV were divided into two groups: 1) detectable HVL (n = 15); and 2) undetectable HVL (n = 22). Subgingival biofilm samples were obtained, and the levels of 35 microbial species were determined by the checkerboard DNA–DNA hybridization method. Periodontal clinical measures and laboratory and sociodemographic data were also registered. x2 test, Fisher exact test, and Mann-Whitney U test were used to compare groups. Multilevel ordinal regression models were used to test the association between HVL and the levels of 35 microbial species in subgingival biofilm, adjusted for confounders. Results: Of the 35 species studied, 11 (31.4%) showed higher mean levels in the detectable HVL group than undetectable HVL group (P

The microbiologic feature of aggressive periodontitis (AgP) in Chinese patients has not yet been determined. This study aims to investigate the prevalence of eight periodontal microorganisms and the distribution of the Porphyromonas gingivalis fimA genotype in a cohort of Chinese patients with AgP.Saliva and pooled subgingival plaque samples were collected from 81 patients with AgP (25 with incisor-first molar type and 56 with generalized type [GAgP]) and 34 periodontally healthy controls. Eight periodontal microorganisms, including Aggregatibacter actinomycetemcomitans, P. gingivalis, Tannerella forsythia, Treponema denticola, Campylobacter rectus, Prevotella intermedia, Prevotella nigrescens, and Fusobacterium nucleatum were detected in these samples by the polymerase chain reaction (PCR). In addition, the distribution of fimA genotypes was assessed in P. gingivalis-positive individuals by PCR.The prevalence of P. gingivalis, T. forsythia, T. denticola, C. rectus, P. intermedia, F. nucleatum, and A. actinomycetemcomitans in patients with AgP was significantly higher than that in healthy controls. The prevalence of A. actinomycetemcomitans in patients with GAgP was relatively low (30.4%) compared with other pathogens. Results of logistic regression analysis showed that younger patients were more likely to harbor A. actinomycetemcomitans (odds ratio = 2.85). Type II was the most prevalent fimA genotype of P. gingivalis in patients with AgP.P. gingivalis, T. forsythia, T. denticola, C. rectus, P. intermedia, and F. nucleatum were the predominant periodontal pathogens of patients with GAgP in China. Type II of fimA was the most prevalent genotype of P. gingivalis in patients with AgP. The prevalence of A. actinomycetemcomitans in patients with GAgP was relatively low.

Coronary artery disease is an inflammatory disorder characterized by narrowing of coronary arteries due to atherosclerotic plaque formation. To date, the accumulated epidemiological evidence supports an association between oral bacterial diseases and coronary artery disease, but has failed to prove a causal link between the two. Due to the recent surge in microbial identification and analyses techniques, a number of bacteria have been independently found in atherosclerotic plaque samples from coronary artery disease patients. In this study, we present meta-analysis from published studies that have independently investigated the presence of bacteria within atherosclerotic plaque samples in coronary artery disease patients. Data were collated from 63 studies covering 1791 patients spread over a decade. Our analysis confirms the presence of 23 oral commensal bacteria, either individually or in co-existence, within atherosclerotic plaques in patients undergoing carotid endarterectomy, catheter-based atherectomy, or similar procedures. Of these 23 bacteria, 5 (Campylobacter rectus, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Prevotella nigrescens) are unique to coronary plaques, while the other 18 are additionally present in non-cardiac organs, and associate with over 30 non-cardiac disorders. We have cataloged the wide spectrum of proteins secreted by above atherosclerotic plaque-associated bacteria, and discuss their possible roles during microbial migration via the bloodstream. We also highlight the prevalence of specific poly-microbial communities within atherosclerotic plaques. This work provides a resource whose immediate implication is the necessity to systematically catalog landscapes of atherosclerotic plaque-associated oral commensal bacteria in human patient populations., Heart disease: Links to oral bacteria A review of bacterial populations in the mouth and in diseased arteries will help research into the role of bacteria in heart disease. Amit Sharma and colleagues at the International Centre for Genetic Engineering and Biotechnology, with co-workers at the All India Institute of Medical Sciences, both in New Delhi, India, analyzed 63 studies covering 1791 patients spread over a decade. They summarize evidence of 23 types of oral bacteria that are also found in atherosclerotic plaques in artery walls. The review also cataloged the proteins secreted by the bacteria and discussed possible involvement of these proteins in the migration of bacteria through the bloodstream. Full genetic details are available for 19 of the 23 bacterial species, which should greatly assist further investigations into the significance of bacteria in the onset of heart disease.

Objective Presently, a large number of individuals consider their companion animals as family members and have close contact with them in daily life. The purpose of the present study was to analyze the distribution of periodontopathic bacterial species in oral specimens taken from dogs and their owners. Design Dental plaque specimens were collected from 66 dogs and 81 members of 64 families who came to an animal clinic or dog training school in Okayama, Japan, in 2011. Bacterial DNA was extracted from each specimen and PCR analyses using primers specific for 11 periodontopathic species, Porphyromonas gingivalis , Porphyromonas gulae , Treponema denticola , Tannerella forsythia , Capnocytophaga ochracea , Capnocytophaga sputigena , Prevotella intermedia , Prevotella nigrescens , Aggregatibacter actinomycetemcomitans , Campylobacter rectus , and Eikenella corrodens were performed. Results P. gulae (71.2%), T. forsythia (77.3%), and C. rectus (66.7%) were frequently found in the dogs, whereas the detection rates of those species in humans were less frequent at 16.0%, 30.9%, and 21.0%, respectively. P. gulae was identified in 13 human subjects and each of their dogs was also positive for the species. Furthermore, E. corrodens and T. denticola in specimens obtained from dogs were correlated with their presence in specimens from owners who had close contact with them. Conclusions These results suggest that several periodontopathic species could be transmitted between humans and their companion dogs, though the distribution of periodontopathic species in both is generally different.

This present study evaluated the subgingival microbiota of the Cebus apella with different periodontal conditions kept by the Tufted Capuchin Monkey Procreation Center (São Paulo State University - UNESP) or free-ranging monkeys. For this purpose, clinical specimens of subgingival biofilm were collected from 52 monkeys, of both genders, 40 kept in captivity and 12 free-ranging monkeys. The primates were submitted to periodontal evaluation and biofilm samples were transferred to VMGA III transport medium and ultrapure water. The microbiota was cultivated in selective and non-selective culture media and microbial DNA was extracted and the presence of periodontal pathogens was evaluated using PCR and real-time PCR. The actinomycetes, fusobacteria, Campylobacter rectus, Eikenella corrodens, black-pigmented Gram-negative anaerobic rods, Tannerella forsythia, staphylococci and streptococci represent the predominantly detected microorganisms. Aggregatibacter actinomycetemcomitans, Dialister pneumosintes and Prevotella nigrescens were rarely observed, whereas Treponema denticola was not found. Populations of C. rectus, E. corrodens, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, T. forsythia and the total microbial load were significantly higher in animals with bone loss and, in smaller extension, in animals with gingival bleeding.

Introduction Acute endodontic infections harbor heterogeneous microbial communities in both the root canal (RC) system and apical tissues. Data comparing the microbial structure and diversity in endodontic infections in related ecosystems, such as RC with necrotic pulp and acute apical abscess (AAA), are scarce in the literature. The aim of this study was to examine the presence of selected endodontic pathogens in paired samples from necrotic RC and AAA using polymerase chain reaction (PCR) followed by the construction of cluster profiles. Methods Paired samples of RC and AAA exudates were collected from 20 subjects and analyzed by PCR for the presence of selected strict and facultative anaerobic strains. The frequency of species was compared between the RC and the AAA samples. A stringent neighboring clustering algorithm was applied to investigate the existence of similar high-order groups of samples. A dendrogram was constructed to show the arrangement of the sample groups produced by the hierarchical clustering. Results All samples harbored bacterial DNA. Porphyromonas endodontalis , Prevotella nigrescens , Filifactor alocis , and Tannerela forsythia were frequently detected in both RC and AAA samples. The selected anaerobic species were distributed in diverse small bacteria consortia. The samples of RC and AAA that presented at least one of the targeted microorganisms were grouped in small clusters. Conclusions Anaerobic species were frequently detected in acute endodontic infections and heterogeneous microbial communities with low clustering behavior were observed in paired samples of RC and AAA.

Short-chain fatty acids (SCFAs) are metabolites from anaerobic periodontopathic bacteria that induce apoptosis in immune cells such as lymphocytes, monocytes and macrophages. However, it remains unclear if SCFAs from pathogens induce apoptosis in monocytes/macrophages similarly with lymphocytes. This study investigated whether SCFAs-induced apoptosis is equal among the immunoregulatory cells. Cell apoptosis of the employed human cells was evaluated after treatment with culture supernatants from various periodontopathic bacteria or sodium butyrate. Apoptosis and viability were determined by detection of DNA fragmentation and using an MTS assay kit, respectively. Porphyromonas gingivalis and Fusobacterium nucleatum culture filtrates strongly induced apoptosis whereas Prevotella nigrescens and Prevotella intermedia culture filtrates failed to induce apoptosis in the THP-1 and U937 human monocyte and macrophage cell lines. Healthy gingival fibroblasts and oral epithelial cells were resistant to all the culture filtrates. Gas-liquid chromatography detected butyric acid in P. gingivalis (21.0-34.0 mM) and F. nucleatum (36.0 mM) in culture filtrates, whereas, only trace levels were seen in P. nigrescens and P. intermedia. These results suggest that butyric acid produced by periodontopathic bacteria severely damages immunoregulatory cells in a consistent manner and, likewise, could be involved in mediating periodontal chronic inflammation.

The occurrence of tooth root caries is increasing as the world population ages and tooth retention in seniors increases. Class V restorations with subgingival margins are difficult to clean and often lead to periodontitis. The objectives of this study were to develop a Class V composite containing dimethylaminohexadecyl methacrylate (DMAHDM) and nanoparticles of amorphous calcium phosphate (NACP), and investigate mechanical properties and the inhibition of six species of periodontitis-related biofilms for the first time.Ethoxylated bisphenol A dimethacrylate (EBPADMA) and pyromellitic glycerol dimethacrylate (PMGDM) were mixed at 1:1 mass ratio to form the resin matrix. DMAHDM, NACP, and glass particles were incorporated at 3%, 20% and 50% by mass, respectively. Six species were tested: Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Enterococcus faecalis. Colony-forming units (CFU), live/dead assay, biomass via crystal violet staining, and polysaccharide production by biofilms were determined on composites.Adding 3% DMAHDM to composite did not affect the flexure strength and elastic modulus (p0.1). For all six species of periodontal pathogens, the DMAHDM composite had biofilm CFU nearly three orders of magnitude less than that without DMAHDM. The killing efficacy of DMAHDM composite against the six species was: E. faecalisF. nucleatumP. nigrescens=P. intermediaA. actinomycetemcomitansP. gingivalis. Biofilm biomass and polysaccharide were also greatly reduced via DMAHDM (p0.05).The novel nanocomposite containing DMAHDM and NACP showed strong inhibiting effect against all six species of periodontitis-related pathogens. This composite is promising for Class V restorations to restore root caries and combat periodontitis.

Palmer LJ, Chapple ILC, Wright HJ, Roberts A, Cooper PR. Extracellular deoxyribonuclease production by periodontal bacteria. J Periodont Res 2012; 47: 439–445. © 2011 John Wiley & Sons A/S Background and Objective: Whilst certain bacteria have long been known to secrete extracellular deoxyribonuclease (DNase), the purpose in microbial physiology was unclear. Recently, however, this enzyme has been demonstrated to confer enhanced virulence, enabling bacteria to evade the host’s immune defence of extruded DNA/chromatin filaments, termed neutrophil extracellular traps (NETs). As NETs have recently been identified in infected periodontal tissue, the aim of this study was to screen periodontal bacteria for extracellular DNase activity. Material and Methods: To determine whether DNase activity was membrane bound or secreted, 34 periodontal bacteria were cultured in broth and on agar plates. Pelleted bacteria and supernatants from broth cultures were analysed for their ability to degrade DNA, with relative activity levels determined using an agarose gel electrophoresis assay. Following culture on DNA-supplemented agar, expression was determined by the presence of a zone of hydrolysis and DNase activity related to colony size. Results: Twenty-seven bacteria, including red and orange complex members Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum, Parvimonas micra, Prevotella intermedia, Streptococcus constellatus, Campylobacter rectus and Prevotella nigrescens, were observed to express extracellular DNase activity. Differences in DNase activity were noted, however, when bacteria were assayed in different culture states. Analysis of the activity of secreted DNase from bacterial broth cultures confirmed their ability to degrade NETs. Conclusion: The present study demonstrates, for the first time, that DNase activity is a relatively common property of bacteria associated with advanced periodontal disease. Further work is required to determine the importance of this bacterial DNase activity in the pathogenesis of periodontitis.

Objective In this study of patients with chronic periodontitis (CP), the severity of the disease and the main periodontal pathogens identified in patients with chronic kidney disease (CKD) were compared with those detected in individuals without systemic disease. Design Nineteen patients with CP without evidence of systemic disease (control group), 25 patients with CP and CKD who were in the pre-dialysis stages (pre-dialysis group), and 22 patients with CP and CKD who were on renal replacement therapy (RRT group) were examined. The severity of CP was based on the investigation of probing depth (PD) and clinical attachment level (CAL). The definition and stage of CKD were based on the criteria proposed by the Kidney Disease Outcomes Quality Initiative of the National Kidney Foundation. Glomerular filtration rate (GFR) was estimated using the equation of Modification of Diet in Renal Disease and the identification of microorganisms in subgingival plaque was performed using polymerase chain reaction (PCR). Results Candida albicans, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola were more common in patients who were on RRT and pre-dialysis than in control subjects. CP was more severe in patients with CKD. A strong association was observed between the frequency of C. albicans (P = 0.056), P.gingivalis (P = 0.008), T. denticola (P = 0.013) and CAL, when CKD patients were compared with the control group. Conclusion CP is more severe and is associated with increased frequency of C. albicans, P. gingivalis, T. forsythia, and T. denticola in patients with CKD.

Yakob M, Soder B, Meurman JH, Jogestrand T, Nowak J, Soder P.-O. Prevotella nigrescens and Porphyromonas gingivalis are associated with signs of carotid atherosclerosis in subjects with and without periodontitis. J Periodont Res 2011; 46: 749–755. ©2011 John Wiley & Sons A/S Background and Objective: Oral microorganisms may be involved in the development of cardiovascular diseases, and Porphyromonas gingivalis is one of the periodontal microorganisms that has been found in carotid atheroma. The aim of this work was to study subgingival microorganisms and early carotid lesions in subjects with and without periodontitis. Material and Methods: Eighty-eight subjects with periodontitis and 40 subjects without periodontitis underwent dental examinations in 2003. The presence of the periodontal microorganisms Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens and Tannerella forsythia was analyzed from subgingival plaque using PCR amplification. The common carotid artery was scanned using ultrasound and the calculated intima-media area (cIMA) was measured. The association between periodontitis, the cIMA value and the presence of periodontal microorganisms, together with several confounders, was studied in a multiple logistic regression model. Results: Smoking [odds ratio (OR) = 5.64; p = 0.001), level of education (OR = 5.02; p

Root canal contents are potent stimuli for proinflammatory cytokines involved in apical periodontitis. This study investigated target gram-negative bacterial species and endotoxins in primary endodontic infection with apical periodontitis, determined their antigenicity against macrophages through the levels of PGE(2), and evaluated their relationship with clinical findings.Samples were taken from 21 root canals with primary infection and apical periodontitis by using paper points. Polymerase chain reaction (16S rDNA) was used for bacterial detection and limulus amebocyte lysate assay for endotoxin measurement. Levels of prostaglandin E2 (PGE(2)) were measured by enzyme-linked immunosorbent assay (Duoset Kit; RD, Minneapolis, MN).Prevotella nigrescens (13/21), Fusobacterium nucleatum (6/21), and Porphyromonas endodontalis (6/21) were the most frequently observed species. A positive association was found between F. nucleatum and P. endodontalis (P.05). A correlation was found between the number of gram-negative bacterial species and the levels of endotoxins, such as PGE(2) (P.05). Higher levels of endotoxin were detected in teeth with exudation, whereas elevated levels of PGE(2) were found in teeth with tenderness to percussion and pain on palpation.Our findings imply an additive effect between the number of gram-negative bacterial species involved in endodontic infection regarding the induction of proinflammatory cytokine by macrophage cells. Moreover, teeth with clinical symptomatology were related to higher levels of endotoxins and PGE(2) secretion.

The aim of our study was to investigate how teenage smoking affects the prevalence of periodontal bacteria and periodontal health with the hypothesis that smoking increases the prevalence of the bacteria. Oral health of 264 adolescents (15- to 16-year-olds) was clinically examined, and their smoking history was recorded. The participants also filled in a structured questionnaire recording their general health and health habits. Pooled subgingival plaque samples were taken for polymerase chain reaction analysis of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola. The prevalence of P. intermedia (21% vs. 4%, p = 0.01) and T. forsythia and T. denticola (23% vs. 8%, p

DGGE of 16S rDNA is one of the most frequently used methods to study microbial communities. In this study, the DGGE profiles of different 16S rDNA regions of the periodontal pathogens Porphyromonas gingivalis, Fusobacterium nucleatum, and Prevotella nigrescens were investigated. The results suggested that V3-V5 and V6-V8 fragments may be suitable for community analysis of subgingival bacteria. Further analysis of subgingival samples with V3-V5 and V6-V8 regions as target fragments suggested that, in chronic periodontitis, re-colonization by periodontal bacteria with a population very similar to the baseline may occur by 6 weeks after mechanical debridement.

Summary: Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans, Tannerella forsythensis and Porphyromonas gingivalis and to a lesser extent Prevotella intermedia and Prevotella nigrescens, are Gram-negative species that are associated with destructive periodontitis. Studies from different parts of the world have shown variable detection rates of periodontal organisms. Hardly any data exist on their carriage in children living in the Middle East. This study was designed to determine the detection of these species in the oral cavity of 240 generally healthy Kuwaiti children, divided into five age groups

Objective: To evaluate changes that occur in the subgingival microbiota after removal of fixed orthodontic appliances using polymerase chain reaction (PCR). Materials and Methods: Thirty orthodontic patients (11 males and 19 females; aged 20 ± 7.3 yr) were included in this study. Subgingival plaque samplings were gathered from the disto-buccal gingival crevice of the left upper central incisors and the left lower central incisors, and from the mesio-buccal gingival crevice of the left upper first molars and the left lower first molars, at two different times: 2 weeks before appliance removal (T1), and 3 months after appliance removal (T2). DNA was extracted from the samples and the 16S rRNA-based PCR detection method was used to determine the prevalence of Actinobacillus actinomycetemcomitans, Tannerella forsythia, Campylobacter rectus, Eikenella corrodens, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola, which are considered as putative periodontopathogens. Results: The frequency of positive sites at T1 and T2 was 65% and 43.3% for C. rectus, and 53.3% and 30.8% for E. corrodens, respectively. For the other bacteria, the frequency tended to be reduced between times. Conclusion: Periodontopathogens during orthodontic treatment were significantly reduced within 3 months of appliance removal. However, how long it takes to return to the preorthodontic composition of the subgingival microbiota and whether it happens at all remain to be seen.

Hydrogen sulfide is one of the predominant volatile sulfur compounds (VSCs) produced by oral bacteria. This study developed and evaluated a system for detecting hydrogen sulfide production by oral bacteria.L-methionine-alpha-deamino-gamma-mercaptomethane-lyase (METase) and beta carbon-sulfur (beta C-S) lyase were used to degrade homocysteine and cysteine, respectively, to produce hydrogen sulfide. Enzymatic reactions resulting in hydrogen sulfide production were assayed by reaction with bismuth trichloride, which forms a black precipitate when mixed with hydrogen sulfide. The enzymatic activities of various oral bacteria that result in hydrogen sulfide production and the capacity of bacteria from periodontal sites to form hydrogen sulfide in reaction mixtures containing L-cysteine or DL-homocysteine were assayed.With L-cysteine as the substrate, Streptococcus anginosus FW73 produced the most hydrogen sulfide, whereas Porphyromonas gingivalis American Type Culture Collection (ATCC) 33277 and W83 and Fusobacterium nucleatum ATCC 10953 produced approximately 35% of the amount produced by the P. gingivalis strains. Finally, the hydrogen sulfide found in subgingival plaque was analyzed. Using bismuth trichloride, the hydrogen sulfide produced by oral bacteria was visually detectable as a black precipitate.Hydrogen sulfide production by oral bacteria was easily analyzed using bismuth trichloride. However, further innovation is required for practical use.

AIM: To look for clinical signs of periodontal disease in young adults who exhibited radiographic bone loss and detectable numbers of Aggregatibacter actinomycetemcomitans in their primary dentition. MATERIAL AND METHODS: Periodontal status and radiographic bone loss were examined in each of the subjects 16 years after the baseline observations. Techniques for anaerobic and selective culture, and checkerboard, were used to detect periodontitis-associated bacterial species. The isolated A. actinomycetemcomitans strains were characterized by polymerase chain reaction. RESULTS: Signs of localized attachment loss were found in three out of the 13 examined subjects. A. actinomycetemcomitans was recovered from six of these subjects and two of these samples were from sites with deepened probing depths and attachment loss. Among the isolated A. actinomycetemcomitans strains, serotypes a-c and e, but not d or f, were found. None of the isolated strains belonged to the highly leucotoxic JP2 clone, and one strain lacked genes for the cytolethal distending toxin. CONCLUSIONS: This study indicates that the presence of A. actinomycetemcomitans and early bone loss in the primary dentition does not necessarily predispose the individual to periodontal attachment loss in the permanent dentition.

Introduction: Prophylactic programs to prevent dental biofilm accumulation must be implemented to minimize the risk for periodontal diseases in orthodontic patients. Therefore, we assessed the possible periodontal and microbiologic changes resulting from the use of 2 methods of orthodontic archwire ligation: elastomeric rings and steel ligatures. Methods: The following parameters were measured: plaque index, gingival bleeding index, probing depth, and biofilm samples from the maxillary second premolars and the mandibular lateral incisors were evaluated in 14 subjects without clinical signs of gingival inflammation before orthodontic appliance placement and after 6 months of treatment. Each orthodontic arch was fixed with elastomeric rings on 1 side of the midline, and steel ligatures were used on the opposite side. Polymerase chain reaction analysis was used to detect Porphyromonas gingivalis , Tannerella forsythia , Actinobacillus actinomycetemcomitans , Prevotella intermedia , and P nigrescens . Results: The elastomeric rings were associated with a higher score for plaque index and bleeding than steel ligatures, as well as many positive sites of T forsythia and P nigrescens ( P Conclusions: Elastomeric rings favored these 2 periodontopathogens and harmed gingival conditions.

Purpose To assess the impact of mechanical debridement (scaling and root planing), without adjunctive therapy, on reducing the numbers of periodontal pathogens detected in pregnant subjects with and without visible third molars. Patients and Methods Sixty-seven subjects in the second trimester of pregnancy were enrolled in an institutional review board-approved study. Full mouth periodontal exams of all teeth were conducted at baseline and postpartum. Presence or absence of third molars was noted. Subgingival biofilm samples were obtained from the mesiobuccal of all first molars at enrollment and postpartum. Subjects' total counts for periodontal pathogens in biofilm samples were determined by DNA-DNA checkerboard hybridization. We analyzed data from a subsample of 26 subjects. All subjects in the study were treated at enrollment by mechanical debridement of all teeth, including third molars. Differences between subjects' baseline and postpartum demographic and clinical characteristics were analyzed by χ2 and t tests by presence or absence of third molars. Statistical significance for differences in pathogen levels was determined by Rank analysis of covariance. Significance was set at 0.05 without correction for multiple comparisons. Results Most of the 26 subjects were African American (61%), on Medicaid (92%), and did not smoke during pregnancy (88%). The 15 subjects with visible third molars were significantly older (28.0 years [SD 6.4] vs 23.7 years [SD 3.9]). In the 11 subjects with no third molars noted, all pathogen counts were reduced postpartum. In the 15 subjects with visible third molars, total counts for each pathogen analyzed were higher postpartum as compared with subjects with no visible third molars, and their bacterial counts were increased for 5 of the 8 pathogens, including all “red cluster” pathogens. Differences between study groups were observed by the presence or absence of third molars for T. forsythia and P. nigrescens (P = .04), and for P. gingivalis, F. nucleatum, total “orange cluster” bacteria, and total pathogens (P Conclusion The efficacy of mechanical debridement to lower periodontal pathogen counts during pregnancy was limited by the presence of visible third molars and should be analyzed further in larger scale trials.

Tissue reactions to bacteria lead to proinflammatory reactions involving matrix metalloproteinases (MMPs). Synthetic protease inhibitors may offer new possibilities to regulate bacterial proteases. We investigated proteolytic activities of certain periodontal bacteria, their effects on the latent proMMP-9, and the effects of synthetic MMP inhibitors and a serine protease inhibitor Pefabloc. The strains studied werePorphyromonas gingivalis, Prevotella intermedia, Peptostreptoccus micros, Prevotella nigrescens, Fusobacterium nucleatum,and5 Aggregatibacter actinomycetemcomitansserotypes. Their gelatinolytic activities and the effects of certain synthetic MMP inhibitors and Pefabloc were analyzed by zymography. Bacterial effects on proMMP-9 conversion were investigated by Western immunoblot. All investigated periodontal bacteria produced gelatinolytic cell-bound and extracellular proteinases which could fragment latent proMMP-9, suggesting co-operative processing cascades in oral tissue remodeling. A. actinomycetemcomitans produced the weakest gelatinolytic activity. Synthetic proteinase inhibitors exhibited slight but clear reductive effects on the bacterial proteolytic activities. We conclude that targeted anti-proteolytic treatment modalities against bacterial-host proteolytic cascades can be developed.

The objective of the present study was to investigate the presence of nine bacterial species in root-filled teeth associated with periapical lesions using a polymerase chain reaction analysis and to correlate these species with clinical features of the cases. DNA was extracted from 45 canal samples of root-filled teeth with periapical lesions. A PCR assay using species-specific primers of 16S rDNA and the downstream intergenic spacer region was used for microbial detection. Enterococcus faecalis was the most prevalent species, detected in 77.8% of the study teeth, followed by Peptostreptococcus micros, detected in 51.1%. Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, and Prevotella nigrescens were detected in 35.6%, 22.2%, 11.1%, and 11.1% of the sampled teeth, respectively. Moreover, PCR detected Filifactor alocis in 26.7%, Treponema denticola in 24.4%, and Tannerella forsythia in 4.4% of the samples. T. denticola and P. micros were statistically associated with tenderness to percussion (p < 0.05). P. nigrescens was associated with the presence of spontaneous pain and abscess (p < 0.05). P. endodontalis and P. nigrescens were associated with purulent exudates (p < 0.05). Synergistic relationship was also observed between some species. The results of this study indicated that E. faecalis was the most frequently identified test species by PCR in teeth with failing endodontic treatment.

Aim. This study aimed at evaluating the prevalence of putative periodontal pathogens (Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Treponema denticola) in saliva of children with mixed dentition at two different time points, correlating these findings with a clinical parameter of gingival health. Design. Polymerase chain reaction (PCR) detection was used to determine the prevalence of these bacteria in saliva of 64 children in 2003 and 60 children in 2004. Gingival health was assessed by gingival index. Result. Sixty-two (96.9%) and 50 (83.3%) children presented low gingival inflammation, whereas 2 (3.1%) and 10 (16.7%) had moderate scores in 2003 and 2004, respectively. Majority of the children (81.3% in 2003 and 73.3% in 2004) had detectable levels of at least one of the bacteria. The prevalence found was of 4.7% and 1.7% for A. actinomycetemcomitans, 6.3% and 8.3% for P. gingivalis, 23.4% and 48.3% for P. nigrescens (P

Background/aims: Periodontitis is a chronic infectious disease associated with a gram-negative subgingival microflora. Bacterial components stimulate, among other receptors, Toll-like receptor (TLR) 2 and/or TLR4. Accumulating evidence indicates that both qualitatively and quantitatively distinct immune responses result from the triggering of TLR2 as compared to TLR4 triggering. The aim was to study the interaction of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Tannerella forsythensis, Prevotella intermedia, Prevotella nigrescens, Fusobacterium nucleatum and Veillonella parvula with TLR2 and TLR4. We investigated all known serotypes (K−, K1–K6) of P. gingivalis and A. actinomycetemcomitans serotype a–e strains for their potency to stimulate cytokine production. Methods: Human embryonic kidney (HEK) cells, stably transfected with CD14, CD14-TLR2, or CD14-TLR4 and whole blood were stimulated with bacterial sonicates. Cytokine production (interleukin-6, -8, -10 and -12) was measured in the supernatant by enzyme-linked immunosorbent assay. Results: All test bacteria stimulated HEK-CD14-TLR2, but only A. actinomycetemcomitans and V. parvula stimulated HEK-CD14-TLR4. No differences were found in the activation of HEK-CD14-TLR2/4, or cytokine production in whole blood between serotypes of P. gingivalis and A. actinomycetemcomitans. Conclusion: Gram-negative periodontal bacteria predominantly stimulated TLR2, which may be of importance for the Th1/Th2 cell orientation of the immune response in periodontitis.