Bacteria In Subgingival Plaque Research Articles

Periodontal treatment causes a longitudinal increase in nitrite-producing bacteria.

The oral microbiome-dependent nitrate (NO3 -)-nitrite (NO2 -)-nitric oxide (NO) pathway may help regulate blood pressure. NO2 --producing bacteria in subgingival plaque are reduced in relative abundance in patients with untreated periodontitis compared with periodontally healthy patients. In periodontitis patients, the NO2 --producing bacteria increase several months after periodontal treatment. The early effects of periodontal treatment on NO2 --producing bacteria and the NO3 --NO2 --NO pathway remain unknown. The aim of this study was to determine how periodontal treatment affects the oral NO2 --producing microbiome and salivary NO3 - and NO2 - levels over time. The subgingival microbiota of 38 periodontitis patients was analysed before (baseline [BL]) and 1, 7 and 90 days after periodontal treatment. Changes in NO2 --producing bacteria and periodontitis-associated bacteria were determined by 16s rRNA Illumina sequencing. Saliva samples were collected at all-time points to determine NO3 - and NO2 - levels using gas-phase chemiluminescence. A significant increase was observed in the relative abundance of NO2 --producing species between BL and all subsequent timepoints (all p<0.001). Periodontitis-associated species decreased at all timepoints, relative to BL (all p<0.02). NO2 --producing species negatively correlated with periodontitis-associated species at all timepoints, with this relationship strongest 90 days post-treatment (ρ=-0.792, p<0.001). Despite these findings, no significant changes were found in salivary NO3 - and NO2 - over time (all p>0.05). Periodontal treatment induced an immediate increase in the relative abundance of health-associated NO2 --producing bacteria. This increase persisted throughout periodontal healing. Future studies should test the effect of periodontal treatment combined with NO3 - intake on periodontal and cardiovascular health.

Real-Time PCR Method as Diagnostic Tool for Detection of Periodontal Pathogens in Patients with Periodontitis.

The most common type of periodontal disease is chronic periodontitis, an inflammatory condition caused by pathogenic bacteria in subgingival plaque. The aim of our study was the development of a real-time PCR test as a diagnostic tool for the detection and differentiation of five periodontopathogenic bacteria, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, and Treponema denticola, in patients with periodontitis. We compared the results of our in-house method with the micro-IDent® semiquantitative commercially available test based on the PCR hybridization method. DNA was isolated from subgingival plaque samples taken from 50 patients and then analyzed by both methods. Comparing the results of the two methods, they show a specificity of 100% for all bacteria. The sensitivity for A. actinomycetemcomitans was 97.5%, for P. gingivalis 96.88%, and for P. intermedia 95.24%. The sensitivity for Tannerella forsythia and T. denticola was 100%. The Spearman correlation factor of two different measurements was 0.976 for A. actinomycetemcomitans, 0.967 for P. gingivalis, 0.949 for P. intermedia, 0.966 for Tannerella forsythia, and 0.917 for T. denticola. In conclusion, the in-house real-time PCR method developed in our laboratory can provide information about relative amount of five bacterial species present in subgingival plaque in patients with periodontitis. It is likely that such a test could be used in dental diagnostics in assessing the efficacy of any treatment to reduce the bacterial burden.

Antibiofilm Effect of Rambutan Leaf Extract (Nephelium lappaceum L.) on Selected Periodontal Pathogens

&#x0D; Introduction: In Indonesia, periodontal disease is one of the dental and oral diseases with the highest prevalence. Bacteria in subgingival plaque can cause periodontal disease, such as Porphyromonas gingivalis and Fusobacterium nucleatum. Herbal medicine has potential as an alternative in the treatment of periodontal disease, for example, rambutan leaves (Nephelium lappaceum L.) are known to have antibacterial properties because they contain flavonoids, tannins, and saponins. Objective: To determine the effects of rambutan leaf extract (Nephelium lappaceum L.) on development of Porphyromonas gingivalis and Fusobacterium nucleatum biofilms. Methods: This study was carried out using the biofilm assay method with crystal violet staining and rambutan leaf extract (Nephelium lappaceum L.) with concentrations of 100%, 50%, 25%, 12.5%, 6.25%, and 3.125% were used as the test material. A microplate reader with a wavelength of 490 nm was used to measure the biofilm density of Porpyromonas gingivalis ATCC 33277 and Fusobacterium nucleatum ATCC 25586. The data obtained were then analyzed statistically using one-way analysis of variance (ANOVA), with a significance level of p&lt;0.05. Results: The most effective concentration of rambutan leaf extract for inhibiting biofilm development at 24 hours incubation was a 100% concentration with an average optical density (OD) of 0.147 against Porphyromonas gingivalis and a 100% concentration with an average OD of 0.077 against Fusobacterium nucleatum. Conclusion: Rambutan leaf extract (Nephelium lappaceum L.) is capable of inhibiting the development of Porphyromonas gingivalis and Fusobacterium nucleatum biofilms, respectively.

Efficacy of the additional use of subgingival air-polishing with erythritol powder in the treatment of periodontitis patients: a randomized controlled clinical trial. Part II: effect on sub-gingival microbiome

ObjectivesTo date, scarce evidence exists around the application of subgingival air-polishing during treatment of severe periodontitis. The aim of this study was to evaluate the effect on the health-related and periodontitis-related subgingival microbiome of air-polishing during non-surgical treatment of deep bleeding pockets in stage III–IV periodontitis patients.Materials and methodsForty patients with stage III–IV periodontitis were selected, and pockets with probing depth (PD) 5–9 mm and bleeding on probing were selected as experimental sites. All patients underwent a full-mouth session of erythritol powder supragingival air-polishing and ultrasonic instrumentation. Test group received additional subgingival air-polishing at experimental sites. Subgingival microbial samples were taken from the maxillary experimental site showing the deepest PD at baseline. Primary outcome of the first part of the present study was the 3-month change in the number of experimental sites. Additional analysis of periodontal pathogens and other sub-gingival plaque bacteria sampled at one experimental site at baseline and 3 months following treatment was performed through a real-time quantitative PCR microarray.ResultsIn the test group, a statistical increase of some health-related species was observed (Abiotropha defectiva, Capnocytophaga sputigena, and Lautropia mirabilis), together with the decrease of pathogens such as of Actinomyces israelii, Catonella morbi, Filifactor alocis, Porphyromonas endodontalis, Sele-nomonas sputigena, Tannerella forsythia, Treponema denticola, and Treponema socranskii. In the control group, statistical significance was found only in the decrease of Filifactor alocis, Tannerella forsythia, and Treponema socranskii.ConclusionsThe addition of erythritol-chlorhexidine powder seems to cause a shift of the periodontal micro-biome toward a more eubiotic condition compared to a conventional treatment. The study was registered on Clinical Trials.gov (NCT04264624).Clinical relevanceSubgingival air-polishing could help re-establishing a eubiotic microbioma in deep bleeding periodontal pockets after initial non-surgical treatment.

Periodontal and Other Oral Bacteria and Risk of Lung Cancer in the Atherosclerosis Risk in Communities (ARIC) Study.

Evidence suggests that periodontal disease is associated with increased lung cancer risk, but whether periodontal pathogens are explanatory is unknown. We prospectively studied associations of prediagnostic circulating antibodies with oral bacteria and of periodontal bacteria in subgingival plaque with lung cancer. We included 4,263 cancer-free participants in the Atherosclerosis Risk in Communities study with previously measured serum IgG antibodies to 18 oral bacteria. In 1,287 participants for whom subgingival plaque was collected, counts for 8 periodontal bacteria were previously measured. Incident lung cancers (N = 118) were ascertained through 2015 (median follow-up = 17.5 years). We used Cox regression to estimate multivariable-adjusted associations, including for sums of antibodies to orange (C. rectus, F. nucleatum, P. intermedia, P. micra, and P. nigrescens) and red (P. gingivalis, T. forsythensis, and T. denticola) complex bacteria. Orange complex bacteria antibodies were positively associated with lung cancer [per IQR hazard ratios (HR) = 1.15; 95% confidence intervals (CI), 1.02-1.29], which was stronger in men (HR = 1.27, 95% CI 1.08-1.49), and explained by P. intermedia and P. nigrescens (HR = 1.15; 95% CI, 1.04-1.26). Suggestive positive associations with lung cancer (N = 40) were observed for F. nucleatum, A. actinomycetemcomitans, and P. gingivalis counts. Significant positive associations were found for the count to antibody ratio for P. intermedia and P. gingivalis. We identified positive associations with lung cancer for oral bacteria, especially orange complex that are moderately pathogenic for periodontal disease. This prospective study supports the need for more research on periodontal bacteria in lung cancer etiology. If associations are supported, this may inform novel lung cancer prevention strategies.

Study on the dynamic changes of oral microbiota in type 2 diabetes patients with periodontitis after initial periodontal therapy

Objectives: To clarify the effect of initial periodontal therapy on the dynamic changes of oral (saliva, dorsal tongue and subgingival plaque) microbiota in periodontitis patients with or without type 2 diabetes mellitus (T2DM). Methods: A total of 14 patients with chronic periodontitis (CP group) and 14 CP patients with T2DM (CP-T2DM group) were included from Department of Periodontology, School and Hospital of Stomatology,Cheeloo College of Medicine, Shandong University. The microbial samples were collected from saliva, dorsal tongue and subgingival plaque of first molars at baseline, 1.5 and 3 months after initial periodontal therapy, and were detected by 16S rRNA (V3-V4 region) gene sequencing. The sequencing data were analyzed to obtain microbial distribution and community structure information. The same professional periodontist evaluated the periodontal status of patients according to periodontitis detection indices before and after initial periodontal therapy. Meanwhile, patients' blood samples were collected and related metabolic indices were evaluated. Results: After initial periodontal therapy, the glycosylated hemoglobin levels [(7.46±1.69)%] in CP-T2DM group were significantly improved than that at baseline [(7.65±1.34)%] (t=0.52,P=0.610). The probing depth of the sampling sites [CP group: (2.94±0.46) mm, CP-T2DM group: (2.95±0.35) mm] and bleeding index (CP group: 1.91±0.42, CP-T2DM group: 1.67±0.49) at 3 months after treatment were significantly decreased than the probing depth [CP group: (3.99±0.77) mm, CP-T2DM group: (3.80±0.76) mm] (F=25.61, P<0.001; F=17.63, P<0.001) and bleeding index (CP group: 3.03±0.52, CP-T2DM group: 2.54±0.65) (F=28.43, P<0.001; F=20.21, P<0.001) at baseline. The flora analysis showed that the α and β diversity indices of the same sites in the CP and CP-T2DM groups did not change significantly before and after the initial therapy, but the bacterial abundance at each site changed. There were commonalities and differences in the microbial composition of each site in the CP and CP-T2DM groups. Among them, the relative abundance of Proteobacteria in saliva and dorsal tongue samples of the two groups after treatment was basically consistent with the change trend in the subgingival plaque microbes. In the subgingival plaque of the CP group, the relative abundance of Proteobacteria showed a gradual increase with the prolongation of initial periodontal therapy; while in the CP-T2DM group, it showed a trend of first increase and then decrease. Syntrophy, Dethiosulfate, Methanobacteriaceae and TG5 in CP and CP-T2DM groups were all significantly dominant bacteria in subgingival plaque at baseline (P<0.05). Moreover, in the CP-T2DM group Spirochetes also showed a significant advantage. At 1.5 months after treatment, Rhizobacteria, Alcaligenes, Comamomons, Delftia, Blautella, etc. were dominant in subgingival plaque (P<0.05). Firmicutes, Clostridia/Clostridiales, Enterococci and Ruminococci showed significant differences at 3 months (P<0.05). Conclusions: Plaques in saliva and tongue dorsal could reflect the effects of initial periodontal therapy on the dynamic changes of microorganisms to a certain extent. CP and CP-T2DM patients had differences in microbial composition and responses to initial periodontal therapy.

The effect of oolong tea as an adjunct to nonsurgical management of chronic periodontitis: A randomized controlled clinical trial

Introduction: Oolong tea, a functional food, has numerous therapeutic benefits owing to the presence of bioactive polyphenols, theasinensins (TS) and catechins. The present study aimed to evaluate the influence of systemic administration of oolong tea as an adjunct to nonsurgical periodontal therapy (NSPT) in the management of chronic periodontitis (CP).Methods: A total of 60 subjects with mild to moderate CP were randomly divided into two groups of tests (n = 30) and the controls (n = 30). They underwent NSPT with adjunctive oolong tea supplementation in the test group only. At baseline, 1, and 3 months, their gingival index (GI), plaque index (PI), probing pocket depth (PPD), clinical attachment loss (CAL), percentage of sites with bleeding on probing (BOP), and lobene stain index (LSI) were recorded. Furthermore, the levels of glutathione peroxidase (GPx), total antioxidants (TAO), and malondialdehyde (MDA) were also estimated in gingival crevicular fluid (GCF), saliva and serum. Additionally, colony-forming units (CFUs) of selective supra and subgingival plaque bacteria were estimated in the plaque samples.Results: In both groups, at 1 month, the GI, PI, BOP, GPx, and TAO levels were improved with a reduction in the levels of MDA and CFU’s and no staining of teeth (P &lt; 0.05). The results were maintained in the test group at 3-month recall visit.Conclusion: Adjunctive administration of oolong tea with NSPT reduced the local and systemic oxidative burden and rapidly resolved the inflammation in CP. This would be specifically beneficial in CP subjects with systemic conditions.

Effect of Treponema Denticola Infection on Epithelial Cells.

Chronic periodontitis is an infectious disease caused by periodontopathic bacteria in subgingival plaque. One major pathogen of this disease, Treponema denticola, has several virulence factors, including a major surface protein (Msp) and the surface protease dentilisin. The cytopathic effects of periodontopathic bacteria on epithelial cells disrupt the integrity of the barrier junction, resulting in the inflammation of periodontal tissue. The aim of this study was to investigate the effect of T. denticola virulence factors dentilisin and Msp on epithelial cells. The effects of T. denticola wild-type, Msp-mutant, and dentilisin-mutant strains on the contact junction in Madin-Darby canine kidney epithelial cells was evaluated based on ohmic values. Cultured oral carcinoma epithelial cells were scratched and exposed to the selected T. denticola strains and cell migration determined. Subsequent degradation of adherence proteins and proteins in the contact junctions was evaluated. Dissociation of cell contact junctions was detected in cells infected with wild-type T. denticola approximately 30 min after infection, but not in those exposed to the mutants. Inhibition of migration was observed in the wild-type and Msp-deficient mutants. The adherent proteins focal adhesion kinase, ZO-1, and paxillin were hydrolyzed by infection with the wild-type and Msp mutants. These results indicate that T. denticola disrupts the function of epithelial cells by hydrolyzing proteins at the intercellular junction and inhibiting healing of epithelial cells via hydrolyzed proteins associated with focal adhesion; Msp was also associated with these effects.

The degree of influence of the types of selected microcultures from subgingival zone on diferent nosological forms of periodontal diseases in young people

The development and course of periodontal disease in young people is characterized by sluggish clinical symptoms, and at the initial stage are asymptomatic, which greatly complicates its timely diagnosis. Therefore, it is especially important to find methods of early diagnosis and prediction of periodontal disease, which will allow for a rational comprehensive prevention. Among the causes of periodontal disease, the main role belongs to the microorganisms of dental plaque, which has important diagnostic value.The aim of the study. To investigate the composition of mixed microcultures of subgingival plaque bacteria in young people with different nosological forms of periodontal disease and to assess the degree of influence of microbial factors on the development of periodontal diseases.Materials and methods. The state of microbiocenosis in the subgingival zone in 104 people with periodontal disease and in 94 people with intact periodontal tissues were studied. To assess the severity of the influence of the types of selected microcultures of the subgingival zone on the development and progression of periodontal disease in young people, the method of alternative sequential analysis of Wald and Bayes’s formula was used.Results. With the development of the inflammatory process in periodontal tissues in most cases revealed cultures characterized by the presence of polymorphic gram-negative bacteria that developed, fixed on the solid phase, and in the liquid phase contained coccal microflora (53.01±5.48 %). During the development of generalized periodontitis, an increasing number of microcultures with a predominance of gram-negative microflora with pronounced adhesive properties was detected, which led to the development of these microcultures on the solid phase (61,9±10,6 %). The calculation of prognostic coefficients showed that the presence of microcultures that developed in the planktonic phase, but contained gram-negative rod-shaped bacteria and cocci were highly important in terms of the development of periodontal disease (+7.46).Conclusions. With the development of the pathological process in periodontal tissues, the state of the microflora changed in the direction of increasing gram-negative polymorphic microflora with pronounced adhesive properties that are capable of aggregation (up to 53.01 % in patients with catarrhal gingivitis, up to 90,48 % – with generalized periodontitis). The result of calculation of the severity of isolated types of microcultures from subgingival zone on the development and progression of periodontal disease in young people showed that the presence of microcultures that developed in the planktonic phase, but contained gram-negative rod-shaped bacteria and cocci were highly important in terms of the development of periodontal disease

Peripheral memory T-cell profile is modified in patients undergoing periodontal management.

T-cells are known to have a role in periodontitis, however, the effect of periodontal therapy on peripheral memory T-cells is unclear. This study evaluated variation in peripheral memory T-cells and red complex bacteria in sub-gingival plaque in patients undergoing periodontal management. Peripheral blood mononuclear cells and sub-gingival plaque were collected from 54 periodontitis patients at baseline, 3-, 6- and 12-months post-therapy and 40 healthy controls. Periodontitis patients were divided into treatment outcome (TxO) groups based on prevalence of sites with probing depth ≥5mm as good (<10% of sites), moderate (10-20%) or poor (>20%) at study conclusion. Naïve (TN -CCR7+ CD45RA+ ), central memory (TCM -CCR7+ CD45RA- ), effector memory (TEM -CCR7- CD45RA- ) and effector memory T-cells re-expressing CD45RA (TEMRA -CCR7- CD45RA+ ) were phenotyped using flow cytometry in CD4+ , CD8+ , CD4+ CD8+ and CD4- CD8- T-cells and red complex bacteria were quantified using qPCR. At baseline, periodontitis subjects had significantly greater mean probing depths and Porphyromonas gingivalis proportions, lower TN but higher CD4+ TCM , CD8+ TCM , CD4+ CD8+ TEM and CD4- CD8- TEM cell proportions compared to health. Periodontal therapy decreased mean probing depths, P.gingivalis proportions, TEM and CD4+ and CD8+ TCM cells, but increased TN and CD4+ and CD8+ TEMRA cells. The T-cell profile in the good TxO group showed therapy-related changes in CD4+ TEM , and CD8+ TN and TEM cells, whereas, no changes were observed in the poor TxO group. Management and the reduction in red complex bacteria were associated with changes in peripheral memory T-cells in periodontitis.

The periodontopathic bacteria in placenta, saliva and subgingival plaque of threatened preterm labor and preterm low birth weight cases: a longitudinal study in Japanese pregnant women.

This study determined the quantity of periodontopathic bacteria in saliva, subgingival plaque, and placenta on the threatened preterm labor (TPL) and preterm low birth weight (PLBW) subjects in order to identify specific periodontal pathogens with high association to adverse pregnancy outcomes. We used real-time PCR with TaqMan probe and ELISA to detect the amount of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, and Prevotella intermedia in subgingival plaque, saliva, and placenta tissue, in addition to serum IgG titers against these bacteria in 28 patients with TPL and 36 healthy pregnant women. Thirteen of 64 births delivered PLBW infants. All 6 periodontopathic bacteria were detected in the placenta samples. The amount of F. nucleatum and detection frequency of T. denticola in placental samples was significantly higher in the TPL group than in the healthy group. Meanwhile, the age, anti-P. gingival IgG in serum, amount of P. gingivalis and T. forsythia in plaque samples, detection frequency of P. intermedia in saliva, and percentage of pocket probing depth ≥ 5mm were higher in TPL-PLBW births than those in TPL-Healthy delivery (HD) group and/or in H-HD group. Ordinal logistic regression analysis revealed that the presence of F. nucleatum in placental tissues was significantly associated with TPL, while the maternal age was significantly associated with PLBW in TPL. Our findings suggested all 6 bacteria may access the placenta. The increased presence of F. nucleatum in placenta might be related to TPL, while advanced maternal age might be associated with PLBW in TPL. Periodontal therapy should be applied to reduce the deep periodontal pocket sites and the colonization of periodontal pathogens in high-risk population.

Differences in the subgingival microbial population of chronic periodontitis in subjects with and without type 2 diabetes mellitus-a systematic review.

The purpose of this systematic review was to evaluate the available evidence in the literature in regard to the subgingival microbial population of chronic periodontitis in subjects with type 2 diabetes mellitus (T2DM+PD) compared to non-diabetic subjects (NDM+PD). A literature search was conducted at Ovid MEDLINE and EMBASE database from 1980 to 2016, supplemented by hand searching as needed. Studies presenting with at least one of the primary outcomes (presence of any subgingival microorganisms, proportion and/or the amount of any subgingival plaque bacteria in T2DM+PD versus NDM+PD) were included. Screening, data extraction and quality assessment were conducted independently and in duplicate. From 611 citations, 19 full-text papers were screened and 11 articles were included for critical appraisal by both reviewers. Some evidence of a difference in the microbial profile between chronic PD subjects with and without T2DM was identified. The strength of evidence is strongest in Tannerella forthysia (T .forsythia) which was reported to be less frequent in the diabetic (T2DM+PD) group in five of the studies, followed by a weaker strength of evidence for other periodontal pathogens such as Porphyromonas gingivalis (P. gingivalis) and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), which were also found less frequent in the diabetic (T2DM+PD) group . Only few studies have compared T2DM+PD with NDM+PD. It is therefore strongly recommended that further studies which include four distinct groups of participants (NDM+PD, T2DM+PD, NDM+NPD, T2DM+NPD) instead of using intra-subject comparisons between healthy and diseased sites of the same subjects. Differences in bacterial populations of T2DM+PD in comparison to NDM+PD subjects may indicate the need of different protocols for the treatment of the diabetic patients with periodontal disease.

Sustained Release of Minocycline From Minocycline-Calcium-Dextran Sulfate Complex Microparticles for Periodontitis Treatment

It is important to address the periodontitis-associated bacteria in the residual subgingival plaque after scaling and root planing to successfully treat periodontitis. In this study, we explored the possibility of exploiting the ion pairing/complexation of minocycline, Ca2+, and sulfate/sulfonate-bearing biopolymers to develop an intrapocket delivery system of minocycline as an adjunct to scaling and root planing. Minocycline-calcium-dextran sulfate complex microparticles were synthesized from minocycline, CaCl2, and dextran sulfate. They were characterized using Fourier-transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. An in vitro release study was conducted to evaluate the release kinetics of minocycline from these microparticles. Agar disk diffusion assays and biofilm-grown bacteria assays were used to assess antibacterial capability. High loading efficiency (96.98% ± 0.12%) and high loading content (44.69% ± 0.03%) for minocycline were observed for these complex microparticles. Mino-Ca-DS microparticles achieved sustained release of minocycline for at least 9 days at pH 7.4 and 18 days at pH 6.4 in phosphate-buffered saline, respectively. They also demonstrated potent antimicrobial effects against Streptococcus mutans and Aggregatibacter actinomycetemcomitans in agar disk diffusion and biofilm assays. These results suggested that the ion pairing/complexation of minocycline, Ca2+, and sulfonate/sulfate-bearing biopolymers can be exploited to develop complex microparticles as local delivery systems for periodontitis treatment.

Periodontal pathogen exposure facilitates disease activity in Systemic Lupus Erythematosus

Abstract This study was undertaken to evaluate whether exposure to subgingival plaque bacteria and periodontal dysbiosis influences disease parameters in systemic lupus erythematosus (SLE). Circulating antibodies to periodontal bacteria are surrogate markers to determine an ongoing bacterial burden, or are indicators of past exposure. SLE patient sera in the Oklahoma Lupus Cohort (n=303) were used to measure antibody titers against periodontal pathogens (A. actinomycetemcomitans, P. gingivalis, and T. denticola) and commensals (C. ochracea and S. gordonii) by ELISA. Correlations between anti-bacterial antibodies and clinical parameters of SLE including autoantibodies, complement, and disease activity (SLEDAI and BILAG) were studied. The effect of oral infection with A. actinomycetemcomitans on SLE in NZM2328 lupus mice was evaluated. SLE patients had varying amounts of antibodies to different oral bacteria. The antibody titers against A. actinomycetemcomitans, P. gingivalis, T. denticola, and C. ochracea were higher in patients positive for anti-dsDNA, and in patients with low complement. Only antibodies to A. actinomycetemcomitans and P. gingivalis, but not T. denticola, were associated with higher disease activity. A. actinomycetemcomitans infected NZM2328 mice developed an increase in histone reactive T cells and an accelerated onset of proteinuria, and lupus nephritis. Our results indicate that exposure to only specific pathogenic periodontal bacteria influences disease activity in SLE patients. The results from lupus mice suggest that this may be due to the amplification of local autoimmunity in response to infection. These findings provide a rationale for assessing and improving periodontal health in SLE patients.

Clinical and microbiological effects of egg yolk antibody againstPorphyromonas gingivalisas an adjunct in the treatment of moderate to severe chronic periodontitis: a randomized placebo-controlled clinical trial

PurposeTo evaluate the clinical and microbiological effects of the local use of egg yolk immunoglobulin against Porphyromonas gingivalis (anti-P.g. IgY) as an adjunct to scaling and root planing (SRP) in the treatment of moderate to severe chronic periodontitis.MethodsThis was a randomized, placebo-controlled, double-blind trial involving 60 systematically healthy patients with moderate to severe chronic periodontitis. Subjects (n=20/group) were randomly assigned to receive SRP combined with subgingival irrigation of anti-P.g. IgY and anti-P.g. IgY mouthwash, subgingival irrigation of 0.2% chlorhexidine and 0.2% chlorhexidine mouthwash, or subgingival irrigation of placebo and placebo mouthwash for 4 weeks. Probing pocket depth, clinical attachment level, bleeding on probing, and the plaque index were evaluated at baseline and at 4 weeks. Subgingival plaque, gingival crevicular fluid, and saliva were simultaneously collected for microbiological analysis.ResultsOur results showed that anti-P.g. IgY mouthwash was as effective as chlorhexidine at improving clinical parameters over a 4-week period. All the groups showed a significant reduction in levels of P.g. at 4 weeks. No significant difference was observed in the test group when compared to placebo regarding the reduction in the levels of P.g. Anti-P.g. IgY significantly suppressed the numbers of red complex bacteria (RCB) in subgingival plaque and saliva in comparison with placebo. No adverse effects were reported in any of the subjects.ConclusionsWithin the limitations of the study, the present investigation showed that passive immunization with anti-P.g. IgY may prove to be effective in the treatment of chronic periodontitis due to its ability to improve clinical parameters and to reduce RCB. No significant differences were found between the anti-P.g. IgY and placebo groups in the reduction of P.g.

Characterization of specimens obtained by different sampling methods for evaluation of periodontal bacteria.

Quantitative analysis of periodontal bacteria is considered useful for clinical diagnosis, evaluation and assessment of the risk of periodontal disease. The purpose of this study was to compare the effectiveness of sampling of saliva, supragingival and subgingival plaque for evaluation of periodontal bacteria. From each of 12 subjects, i) subgingival plaque was collected from the deepest pocket using a sterile paper point, ii) stimulated whole saliva was collected after chewing gum, and iii) supragingival plaque was collected using a tooth brush. These samples were sent to the medical examination laboratory for quantitative analysis of the counts of three periodontal bacterial species: Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia. The proportions of these bacteria in subgingival plaque were higher than those in saliva or supragingival plaque, but lower in subgingival plaque than in saliva or supragingival plaque. In several cases, periodontal bacteria were below the levels of detection in subgingival plaque. We concluded that samples taken from subgingival plaque may be more useful for evaluating the proportion of periodontal bacteria in deep pockets than is the case for other samples. Therefore, for evaluation of periodontal bacteria, clinicians should consider the characteristics of the specimens obtained using different sampling methods.

Elevated MicroRNA-128 in Periodontitis Mitigates Tumor Necrosis Factor-α Response via p38 Signaling Pathway in Macrophages.

Periodontitis is a chronic inflammatory disease resulting from an inflammatory response to subgingival plaque bacteria, including Porphyromonas gingivalis. MicroRNA (miRNA) is a current focus in regulating the inflammatory processes. In this study, the inflammatory miRNA expression in gingival tissues of patients with periodontitis and of healthy individuals is compared, and its role in regulating the inflammatory response is examined. Gingival tissues from patients with periodontitis and healthy individuals were collected for miRNA microarray. THP-1 and CA9-22 cells were challenged with P. gingivalis, and miRNA expression was determined by real-time polymerase chain reaction. Target genes for miRNA were predicted using TargetScanHuman database, and miRNA gene expressions were reviewed using public databases. For the functional study, THP-1 cells were transfected with a miRNA-128 mimic, and target gene expression was compared with THP-1 cells challenged with P. gingivalis. For the tolerance test, THP-1 cells transfected with miRNA-128 mimic were treated with phorbol 12-myristate 13-acetate (PMA) or paraformaldehyde (PFA)-fixed Escherichia coli. Tumor necrosis factor (TNF)-α production was determined by enzyme-linked immunosorbent assay, and mitogen-activated protein kinase (MAPK) protein phosphorylation was determined by Western blot. Gingival tissues from patients with periodontitis showed increased expression of miRNA-128, miRNA-34a, and miRNA-381 and decreased expression of miRNA-15b, miRNA-211, miRNA-372, and miRNA-656. THP-1 cells and CA9-22 cells challenged with P. gingivalis showed increased miRNA-128 expression. Among the predicted miRNA-128 target genes, several genes that are involved in MAPK signaling pathway showed similar gene expression pattern between P. gingivalis challenge and miRNA-128 mimic transfection. In THP-1 cells transfected with miRNA-128 mimic, TNF-α production was lower, and phosphorylation of p38 was inhibited when challenged with PMA or PFA-fixed E. coli. miRNA-128 may be involved in mitigating the inflammatory response induced by P. gingivalis in periodontitis.

Lysine-specific proteolytic activity responsible for forsythia detaching factor modification

ObjectivesThe objective of the present study was to clarify the lysine-specific proteolytic activity derived from periodontal pathogens responsible for Forsythia detaching factor (FDF) modification. DesignThe activity responsible for FDF modification in Tannerella forsythia and Porphyromonas gingivalis were evaluated by colorimetric assay using Ac-Arg-Ala-Lys-p-nitroaniline as a substrate. FDF modification in T. forsythia and P. gingivalis were evaluated by Western blotting using recombinant FDF (rFDF) as a substrate. Furthermore, the activity in GCF of 20 patients with periodontitis and 10 healthy subjects was also evaluated by colorimetric assay. Bacteria in subgingival plaque were detected using polymerase chain reaction. ResultsThe activity of both bacteria in colorimetric assay were 21.35 unit (P. gingivalis) and 3.61 unit (T. forsythia), respectively. Western blot analysis revealed that P. gingivalis was found to efficiently degrade rFDF and T. forsythia partially cleaved rFDF. The activity in GCF from patients with periodontitis (clinically healthy sites: CH, deep bleeding sites: DB and deep non-bleeding sites: DNB) was significantly higher than those from healthy subjects (healthy sites: H). Among the patients with periodontitis, the activity from CH was significantly lower than those from DB and DNB. T. forsythia was detected in 68.4% of DNB, in 78.4% of DB and in none of CH. P. gingivalis was detected in 63.2% of DNB, in 84.0% of DB and in 10.5% of CH. No bacterium was detected in healthy subjects. ConclusionThe lysine-specific proteolytic activity responsible for FDF modification correlates with the presence of major periodontal pathogens.

English

The purpose of this investigation was to define the cultivable oral microflora in supragingival and subgingival plaques of Algerian healthy adults. Supragingival and subgingival plaque samples were collected from 65 Algerian caries-free, periodontally healthy subjects. Samples were taken from approximal surfaces and analysed for bacterial content after being inoculated on non-selective and selective media and incubated under different atmospheres; aerobic, capnophilic and anaerobic. The standard identification procedures by biochemical tests were used. Pearson’s Chi-square χ2 test (P 0.05, χ2-test) with the predominance of enterococci which were isolated even from supragingival and subgingival plaques in considerable proportions. The supragingival bacterial flora in healthy adults was composed mainly of Gram positive cocci and anaerobic Gram positive rods with the predominance of Streptococci and Actinomyces naeslundii, respectively; whereas, anaerobic Gram negative rods and facultative anaerobic Gram positive cocci were the predominant bacteria in subgingival plaque. Keys words: Oral microflora, dental biofilm, supragingival plaque, subgingival plaque, cultivable bacteria, healthy adults.

Serum ferritin level and red blood cell parameters in healthy controls and chronic periodontitis patients.

Periodontitis, which is a chronic inflammatory disease causes reduction in the number of erythrocytes and hemoglobin. It is found to be caused by specific pathogenic subgingival plaque bacteria. Periodontitis is host mediated through release of pro inflammatory cytokines by local tissues and immune cells in response to bacterial flora and its products, especially lipopolysacharides. Periodontitis is found to have systemic effect and the cytokines produced inhibit proliferation and differentiation of erythrocytes leading to anaemia. This study evaluate level of hemoglobin erythrocytes, hematocrit and serum ferritin levels in healthy subjects and periodontitis patient.