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An intuitive, clinically relevant index of microbial dysbiosis as a summary statistic of subgingival microbiome profiles is needed. Here, we describe a subgingival microbial dysbiosis index (SMDI) based on machine learning analysis of published periodontitis/health 16S microbiome data. The raw sequencing data, split into training and test sets, were quality filtered, taxonomically assigned to the species level, and centered log-ratio transformed. The training data set was subject to random forest analysis to identify discriminating species (DS) between periodontitis and health. DS lists, compiled by various “Gini” importance score cutoffs, were used to compute the SMDI for samples in the training and test data sets as the mean centered log-ratio abundance of periodontitis-associated species subtracted by that of health-associated ones. Diagnostic accuracy was assessed with receiver operating characteristic analysis. An SMDI based on 49 DS provided the highest accuracy with areas under the curve of 0.96 and 0.92 in the training and test data sets, respectively, and ranged from −6 (most normobiotic) to 5 (most dysbiotic) with a value around zero discriminating most of the periodontitis and healthy samples. The top periodontitis-associated DS were Treponema denticola, Mogibacterium timidum, Fretibacterium spp., and Tannerella forsythia, while Actinomyces naeslundii and Streptococcus sanguinis were the top health-associated DS. The index was highly reproducible by hypervariable region. Applying the index to additional test data sets in which nitrate had been used to modulate the microbiome demonstrated that nitrate has dysbiosis-lowering properties in vitro and in vivo. Finally, 3 genera ( Treponema, Fretibacterium, and Actinomyces) were identified that could be used for calculation of a simplified SMDI with comparable accuracy. In conclusion, we have developed a nonbiased, reproducible, and easy-to-interpret index that can be used to identify patients/sites at risk of periodontitis, to assess the microbial response to treatment, and, importantly, as a quantitative tool in microbiome modulation studies.

Purpose: To investigate the prevalence of periodontal disease(s) and the associated bacteria among rheumatoid arthritis (RA) patients treated with different immunosuppressive drugs.Methods: Patients aged 18 – 65 years who had a 6-month history of RA, and were diagnosed as per the American College of Rheumatology and European League against Rheumatism, were included in the study. Supragingival plaque was removed by dentists. Using sterile paper strips, sub-gingival biofilm samples were collected from 5 of the deepest periodontal pockets. The samples were sent to pathologists for assessment. Polymerase chain reaction was carried out on them. Detection thresholds were >102 for Aggregatibacter actinomycetemcomitans, while the detection threshold for Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum, Campylobacter rectus, Eubacterium nodatum, Eikenellacorrodens, and Capnocytophaga species was 103.Results: There was a higher number of patients with bleeding-on-probing amongst cohorts who received a combination of methotrexate and tumor necrosis factor-α antagonist than in those given leflunomide only (52 vs. 29, p = 0.041, q = 3.064), or methotrexate + rituximab (52 vs. 30, p = 0.041, q = 3.131, Fig. 1). Papilla bleeding index was lowest in patients who were treated with leflunomide. Almost all patients had dental infection with Fusobacterium nucleatum.Conclusion: These results indicate that treatment of RA with methotrexate results in periodontal inflammation.

Introduction. The associative role of the bacterial factor in the development of both primary malignant tumors of the oral mucosa and relapses is being actively discussed today. In the article published earlier, we have already described the possible mechanisms of action of periodontopathogenic microflora and its connection with the development of squamous cell carcinoma of the oral mucosa through cell proliferation, intracellular accumulation of pathogen, DNA replication and affect the signaling pathways of MARK (mitogen-activated protein kinase).Objective – to analyze the impact of periodontal pathogens on the risk of oral squamous cell carcinoma and its recurrence, as well as to evaluate the role of polymerase chain reaction and bacterial culture in the diagnosis of squamous cell carcinoma.Materials and methods. This study included 35 patients with stage Т3–4 squamous cell carcinoma, whose tumor tissue samples were tested for periodontal pathogens using culture and PCR. We analyzed 5 paraffin-embedded and 30 frozen tissue blocks from newly diagnosed (n = 15) and re-treatment (n = 15) patients.Results. We found that PCR was more sensitive than culture for the detection of possible etiological agents and predictors of squamous cell carcinoma (including Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola) (р Tannerella forsythia and Treponema denticola were detected only using PCR, whereas all cultures were negative. However, conventional culture proved to be more effective than PCR for the detection of Prevotella intermedia. Between 3 % and 100 % of newly diagnosed patients tested positive for Treponema denticola and some other periodontal pathogens (PCR) developed relapses, whereas among re-treatment patients, this proportion was 66.6 %.Conclusion. The combination of the culture method and the polymerase chain reaction method in the study of periodontopathogenic microflora has shown high efficiency in identifying possible predictors of squamous cell carcinoma of the oral mucosa and in preventing the development of chronic infectious periodontal diseases.

The quantitative polymerase chain reaction (qPCR) is a variant of PCR aimed to detect and quantify a targeted DNA molecule through the addition of probes labeled with fluorescent molecules that emit fluorescence within each amplification cycle, what results in fluorescence values proportional to the amount of accumulated PCR product. This chapter presents the detailed procedures for quantification of different periodontal pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Campylobacter rectus, and Fusobacterium spp.) using qPCR. It also includes the description of the most frequent problems encountered and how to solve them. In addition, a detailed protocol for multiplex qPCR to detect and quantify P. gingivalis and A. actinomycetemcomitans is included.

Probiotics have aroused great interest as an adjunctive treatment to periodontal therapy, due to the frequent colonisation by periodontopathogens after therapy. The aim of this systematic review was to analyse in the scientific literature, evidence of the microbiological effects of probiotics as an adjunct to periodontal therapy in the treatment of periodontal diseases (PD). Only randomised controlled trials (RCT), evaluating the microbiological effect of probiotics as an adjunct to periodontal therapy. The authors conducted a search in PubMed/MEDLINE, LILACS, ScienceDirect, Web of Science and Cochrane Library to identify articles published in English until February 2020. The quality of the studies was assessed using the JADAD scale and the risk of bias was assessed according to the Cochrane Collaboration assessment tool. Of the 265 articles potentially relevant to this review, 10 studies were included. The most frequently used probiotic bacteria were those of the genus Lactobacillus spp. and the time of administration of the probiotics was between 14 days to 3 months. Most studies have shown that the adjuvant use of probiotics reduces the total mean counts of gram-negative anaerobic species (Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola and Prevotella intermedia) and gram-negative coccobacillus (Aggregatibacter actinomycetemcomitans) of subgingival plaque samples. Probiotics adjuvant to periodontal therapy reduces periodontopathogenic species in a greater proportion, compared only to periodontal therapy. Especially the Lactobacillus reuteri strain, without combination with other strains, offered a greater reduction in pathogenic bacteria associated with greater destruction of periodontal tissues and deep periodontal pockets. Researchers should perform high-quality RCT, evaluating single strains without combinations, in order to observe the microbiological benefits as adjunctive treatment of PD.

This study assessed the levels of tumor necrosis factor-α (TNF-α), prostaglandin E2 (PGE2), receptor activator of nuclear factor kappa B (RANK), RANK ligand (RANKL), osteoprotegerin (OPG), and levels of Fusobacterium nucleatum, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Prevotella intermedia, and Streptococcus oralis in areas where airborne particle-abraded, large-grit, acid-etched (SLA), fluorine-modified, and anodized implant surfaces are used. A total of 71 implants from 37 patients were assessed, grouped according to the surface characteristics of the implants: SLA surface (Group 1), fluorine-modified surface (Group 2), and anodized surface (Group 3). The following clinical indices were measured: Gingival Index (GI), probing depth (PD), bleeding on probing (BOP), clinical attachment level (CAL), and keratinized tissue width (KTW). Peri-implant sulcus fluid and subgingival plaque samples were also collected. Commercial enzyme-linked immunosorbent assay (ELISA) kits were purchased for measuring TNF-α, PGE2, RANKL, RANK, and OPG. Real-time quantitative polymerase chain reaction (PCR) was used to detect P intermedia, T forsythia, T denticola, F nucleatum, P gingivalis, and S oralis levels in the subgingival biofilms. The groups showed no statistically significant differences in GI, PD, BOP, CAL, KTW, or peri-implant status. The total amounts of PGE2, TNF-α, RANKL, RANK, and OPG and the RANKL/OPG ratio were not significantly different between groups. F nucleatum, T forsythia, P intermedia, P gingivalis, and T denticola were significantly higher in Group 3 implants. DNA concentrations of S oralis were higher in Group 2. Within the limitations of this study, SLA and fluorine-modified implant surfaces may be more clinically successful than anodized-surface implants.

Introduction: Tannerella forsythia, is an anaerobic, Gram-negative microorganism closely related to periodontal disease. Factors such as poor dental hygiene, fixed orthodontic appliances, etc. can cause dysbiosis in the bacterial community. Objective: To analyze the literature about the epidemiology, diagnostic methods, oral manifestations, relationship with systemic diseases and treatment of Tannerella forsythia in orthodontic patients. Methodology: Using the keywords “T. forsythia”, “orthodontics”, “oral manifestations”, “diagnostics”, “treatment” and “epidemiology”, the main public databases were searched, with emphasis on the last 5 years. It was evaluated with the PRISMA and AMSTAR-2 guidelines. Results: At the national level, in 2019, cases of gingivitis and periodontal disease ranked fifth among the twenty main causes of diseases. As a diagnostic method, most of the studies used molecular biology (PCR) for the identification of bacterial DNA. Very few studies performed cultures for identification. T. forsythia is capable of inducing characteristic signs of gingivitis and periodontal disease. Non-surgical mechanical therapy remains the gold standard in its treatment. There are multiple diseases that can be related to the presence of T. forsythia, so its medical importance becomes more relevant and its control, essential. Conclusion: T. forsythia is closely related to periodontal disease. Its presence is mainly found in the easily accumulated plaque in patients with fixed appliances. It is essential to diagnose it for a treatment that can avoid harm to the patient.

Increasing attention has been paid to the possible link between periodontal disease and atherosclerosis over the past decade. The aim of this study is to investigate the presence of five periopathogens: Porphyromonas gingivalis (P.g.), Aggregatibacter actinomycetemcomitans (A.a.), Tannerella forsythia (T.f.), Treponema denticola (T.d.), and Prevotella intermedia (P.i.) in atheromatous plaques obtained from the carotid and coronary arteries in patients who underwent coronary artery bypass graft surgery and carotid endarterectomy. Group I (carotid arteries) consisted of 30 patients (mean age: 54.5 ± 14.8 ), and group II (coronary arteries) consisted of 28 patients (mean age: 63 ± 12.1 ). Clinical periodontal examinations consisted of plaque index, gingival index, sulcus bleeding index, and periodontal probing depth and were performed on the day of vascular surgery. The presence of periopathogens in periodontal pockets and atherosclerotic vessels was detected using polymerase chain reaction. In both subgingival plaque and atherosclerotic plaque of carotid arteries, P.g., A.a., T.f., T.d., and P.i. were detected in 26.7%, 6.7%, 66.7%, 10.0%, and 20.0%, respectively, while for coronary arteries, P.g. was detected in 39.3%, A.a. in 25%, T.f. in 46.4%, T.d. in 7.1%, and P.i. in 35.7%. The presence of five periopathogens in carotid and coronary atherosclerotic vessels showed correlation in regard to the degree of periodontal inflammation. The present study suggests the relationship between periodontal pathogenic bacteria and atherogenesis. Further studies are necessary in relation to the prevention or treatment of periodontal disease that would result in reduced mortality and morbidity associated with atherosclerosis.

Background Clinical benefits of local antibiotics as an adjunct to nonsurgical treatment of peri-implantitis have been widely reported, but most studies evaluated incipient peri-implantitis lesions, and showed incomplete treatment success rates. Purpose To assess the clinical and microbiological outcomes of administering metronidazole in combination with minocycline as a local adjunct to the nonsurgical treatment of peri-implantitis. Materials and methods One hundred and eighteen subjects with peri-implantitis were recruited in a four-center, three-arm, and 12-week randomized controlled trial. Subjects were randomly assigned to receive one of the following treatments: (a) MM-mechanical debridement + metronidazole-minocycline ointment, (b) MC-mechanical debridement + minocycline ointment, (c) NST-mechanical debridement only. Results Except for four subjects who was excluded during the trial, a total of 114 patients with 114 implants (one implant per each patient) finally completed the trial and were included in the analyses. Multivariate logistic regression analysis revealed that the treatment success rates (absence of bleeding or suppuration on probing, and sites showing pocket probing depth [PPD] ≥5 mm) on at 12 weeks were higher in MM-group patients (31.6%) and MC-group patients (20.5%) compared to NST-group patients (2.7%; p = 0.011 and 0.040, respectively). Subjects with deepest PPD ≥8 mm showed a significant difference in the PPD reduction between MM and MC groups at week 4 (p = 0.025) and week 12 (p = 0.047). Detection ratio of Tannerella forsythia was significantly lower for MM group than MC group (p = 0.038). Conclusions Additive use of either MM or MC results in significantly higher treatment success rates compared to sole mechanical debridement in nonsurgical treatment of peri-implantitis. Moreover, MM contributes to a significantly greater reduction in the PPD compared to MC in deep pockets (cris.nih.go.kr KCT0004557).

Aims: We evaluated the effect of chitosan gel on total oral bacteria, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola, during orthodontic treatment with mini-implants. Material and methods: Thirty subjects with 52 orthodontic mini-implants were divided into three groups: one group was treated with chitosan gel, the other group with chlorhexidine gel, and the control group with placebo. The plaque of the orthodontic peri-mini-implant area was collected before and after gel treatment. The total oral bacteria and red-complex bacteria of P. pingivalis, T. forsythia, and T. denticola were determined with reverse transcription-quantitative PCR. Results: Thirty-four orthodontic mini-implants (65.38%) appeared as healthy and showed no clinical signs of inflammation. The total number of bacteria was reduced after chitosan gel application. The highest decrease in the proportion of P. gingivalis was observed in the chlorhexidine gel application group, which showed a value of 70.86%, whereas the chitosan gel application showed a reduction of only 26.59%, and the control gel application showed the lowest reduction effect of only 2.55%. The difference in the reduction between gel application groups was significant (P

Objectives To investigate common pathogenic bacteria of periodontal diseases (PD) in patients with type 2 diabetes mellitus (T2DM) and its relationship with PD severity, glycemic control and body mass index (BMI). Material and Methods This case–control study consisted of 55 patients with T2DM and 55 individuals as control. Samples were collected from periodontal pockets. After DNA extraction, using 16srRNA‐specific primers, the presence of Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Prevotella intermedia (Pi), and Fusobacterium nucleatum (Fn) were examined based on polymerase chain reaction method. Results Aa frequency was significantly higher in in T2DM group than control. There were no significant differences in the frequencies of Pg, Tf, Pi, and Fn between studied groups. There were no significant differences between frequencies of studied bacteria in different severities of periodontitis in T2DM group. Prevalence of Tf in T2DM patients with moderate periodontitis was significantly higher than non‐diabetics with moderate periodontitis. There was no significant difference between the frequency of bacteria in diabetics with good and poor glycemic control. There was a significant difference between the frequencies of Pg in T2DM individuals with different BMI levels. Conclusions A higher frequency of detection of Aa was found in diabetic when compared to non‐diabetics. Glycemic control did not affect the frequency distribution of studied bacteria in T2DM. Pg was identified in higher frequency in overweight T2DM patients.

Objective To determine the efficacy of a gel containing propolis extract, nanovitamin C and nanovitamin E as adjuvant to mechanical debridement in the treatment of peri-implant mucositis (PM). Background Propolis has anti-inflammatory and antibacterial effect that may improve peri-implant health. Methods A randomized, double-blind study was performed on patients with at least one implant with PM. Participants received a professional prophylaxis and were instructed to use either test or a control gel as toothpaste three times/day for 1 month. Clinical and microbiological parameters were evaluated. PM resolution was considered in absence of bleeding on probing (BOP). Data were analysed with Mann-Whitney U, Wilcoxon signed-rank and chi-square tests. Results Forty-six patients participated (23 in each group). After treatment, 26.1% of test patients showed complete PM resolution versus 0% in control group (p = .02). Significant reductions were observed in plaque index (p = .03), BOP (p = .04) and probing depths (p = .027) in test compared with control group. The reduction in Tannerella forsythia was statistically greater in test than in control group at 1-month follow-up (p = .02). Porphyromonas gingivalis was statistically reduced in test group from baseline to 1-month follow-up (p = .05). Conclusion Test gel clinically improved PM and showed certain antimicrobial effect after 1 month in comparison with control group. Further long-term clinical trials are required to confirm these results.

BACKGROUND: Oral infections associate statistically with cancer. OBJECTIVE: We hypothesized that certain periodontal microorganisms might specifically link to malignancies in general and set out to investigate this in our ongoing cohort study. METHODS: A sample of 99 clinically examined patients from our cohort of 1676 subjects was used to statistically investigate the associations between harboring periodontal microorganisms Aggregatibacter actinomycetemcomitans (A.a), Porphyromonas gingivalis (P.g), Prevotella intermedia (P.i), Tannerella forsythia (T.f) and Treponema denticola (T.d). We used oral infection indexes and the incidence figures of malignancies as registered in 2008–2016 in the Swedish National Cancer Register. RESULTS: The pathogen A.a showed strong association with malignancy in 32 out of the 99 patients while P.g and P.i were more prevalent among patients without malignancy. In principal component analyses, A.a appeared in the strongest component while the second strongest component consisted of a combination of T.f and T.d. The third component consisted of a combination of P.g and P.i, respectively. Of basic and oral health variables, gingival index appeared to be the strongest expression of inflammation (Eigen value 4.11 and Explained Variance 68.44 percent). CONCLUSIONS: The results partly confirmed our hypothesis by showing that harboring certain periodontal bacteria might link to malignancy. However, the associations are statistical and no conclusions can be drawn about causality.

Objective This study evaluated the metabolic activity of hydro-carbon-oxo-borate complex (HCOBc) on a multispecies subgingival biofilm as well as its effects on cytotoxicity. Materials and methods The subgingival biofilm with 32 species related to periodontitis was formed in the Calgary Biofilm Device (CBD) for 7 days. Two different therapeutic schemes were adopted: (1) treatment with HCOBc, 0.12% chlorhexidine (CHX), and negative control group (without treatment) from day 3 until day 6, two times a day for 1 min each time, totaling 8 treatments and (2) a 24-h treatment on a biofilm grown for 6 days. After 7 days of formation, biofilm metabolic activity was determined by colorimetry assay, and bacterial counts and proportions of complexes were determined by DNA-DNA hybridization. Both substances’ cytotoxicity was evaluated by cell viability (XTT assay) and clonogenic survival assay on ovary epithelial CHO-K1 cells and an osteoblast precursor from calvaria MC3T3-E1 cells. Results The first treatment scheme resulted in a significant reduction in biofilm’s metabolic activity by means of 77% by HCOBc and CHX treatments versus negative control. The total count of 11 and 25 species were decreased by treatment with hydro-carbon-oxo-borate complex and CHX, respectively, compared with the group without treatment (p < 0.05), highlighting a reduction in the levels of Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, and Fusobacterium periodontium. CHX significantly reduced the count of 10 microorganisms compared to the group treated with HCOBc (p < 0.05). HCOBc and CHX significantly decreased the pathogenic red-complex proportion compared with control-treated biofilm, and HCOBc had even a more significant effect on the red complex than CHX had (p ≤ 0.05). For the second treatment scheme, HCOBc complex and CHX significantly decreased 61 and 72% of control biofilms’ metabolic activity and the counts of 27 and 26 species, respectively. HCOBc complex did not significantly affect the proportions of formed biofilms, while CHX significantly reduced red, orange, and yellow complexes. Both substances exhibited similar cytotoxicity results. Conclusions This short communication suggested that the HCOBc complex reduced a smaller number of bacterial species when compared to chlorhexidine during subgingival biofilm formation, but it was better than chlorhexidine in reducing red-complex bacterial proportions. Although HCOBc reduced the mature 6-day-old subgingival multispecies biofilms, it did not modify bacterial complexes’ ratios as chlorhexidine did on the biofilms mentioned above. Future in vivo studies are needed to validate these results. Clinical relevance HCOBc complex could be used to reduce red-complex periodontal bacterial proportions.

While no single species has been implicated as the primary pathogen and the available evidence is consistent with a polymicrobial disease etiology, the red-complex bacteria consisting of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia has been strongly implicated in the onset of periodontitis a chronic inflammatory disease affecting the supporting tissues of the teeth in the oral cavity. Chronic inflammation is believed to act as catalyst for tumour development and progression

Nowadays racial and ethnic differences in health care has become a growing concern. It is one of the critical determinant in influencing the genotype of the host in which may results in some diseases such as periodontal disease. Tannerella forsythia can be found in oral cavity and have the strongest relation in resulting on the destruction of connective tissue in periodontal disease. This research is aim to investigate the prevalence of periodontal pathogens, particularly T. forsythia in four major ethnic groups in Sarawak which may result in periodontal disease in Sarawak. This disease may due to the results from the infection of the tissue supporting the teeth. A total of (n = 40) saliva samples consist of 10 samples for each ethnic groups such as Iban, Malay, Chinese and Bidayuh were collected in Kuching and Kota Samarahan using culture-independent method. The DNA was extracted from saliva based on Phenol Chloroform Isoamyl Alcohol method. After that, 16S rRNA gene was then amplified via PCR for bacterial detection using 27 F and 1492 R primers, followed by PG-F and PG-R primers set in identifying T. forsythia. The PCR product was observed on 1.5% gel electrophoresis. As a result, the presence of bacteria T. forsythia was found more frequently from saliva samples of ethnic in Iban (70%), followed by Malay (60%), Bidayuh (60%) and lastly Chinese (50%). The differences of demographic, certain cultural beliefs and practices might affect the oral health status. This finding show that it may help to identify the risk groups and has contributed an additional evidence for the association between ethnicity and periodontal disease.

Gingival enlargement is a common complication of treatment with a fixed orthodontic appliance, biocompatible stainless-steel archwires AISI 304L (SS). Due to the retention areas, dental plaque accumulation is increased, which results in anaerobic conditions, favourable for periodontopathogenic bacteria. Therefore, it is reasonable to assume that periodontopathogenic bacteria can be found in patients with fixed orthodontic appliances. Organic deposits on the surface of archwires were analyzed. Twenty-one patients with fixed orthodontic appliances and gingival enlargement in the upper dental arch were included in the study. For a determination of the periodontopathogenic bacteria Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Treponema denticola the molecular microbiological method GenoType Test System was used. For the surface analysis of new and in-vivo exposed SS archwires X-ray Photoelectron Spectroscopy was used. The average probing depth at the baseline was 3.76±0.85 mm. Three types of periodontopathogenic bacteria, namely A. actinomycetemcomitans, T. forsythia and T. denticola, were found to be present. The thickeness of the thin oxide film on new archwires was 8 nm, while organic deposits on the in-vivo exposed archwires was estimated to 60–80 nm. Anaerobic periodontopathogenic bacteria can be found in patients with fixed orthodontic appliances. Therefore, special care is recommended during this kind of treatment.

Red complex organisms are a group of organisms (Porphyromonas gingivalis ATCC 33277, Treponema denticola ATCC 35405, Tannerella forsythia ATCC 43037) that have been identified for the causation of periodontal diseases. Aspirin and diclofenac have been used as regular analgesics. Therefore, it is of interest to document the identification of aspirin and diclofenac binding proteins in the red complex pathogens using the STITCH v.5 pipeline. The virulence properties of these proteins were analyzed using VICMPred and VirulentPred software. Thus, we document 000 number of proteins having optimal binding features with the known analgesics.

Smoking is a risk factor for periodontal disease, and a cause of oral microbiome dysbiosis. While this has been evaluated for traditional cigarette smoking, there is limited research on the effect of other tobacco types on the oral microbiome. This study investigates subgingival microbiome composition in smokers of different tobacco types and their effect on periodontal health. Subgingival plaques were collected from 40 individuals, including smokers of either cigarettes, medwakh, or shisha, and non-smokers seeking dental treatment at the University Dental Hospital in Sharjah, United Arab Emirates. The entire (~ 1500 bp) 16S rRNA bacterial gene was fully amplified and sequenced using Oxford Nanopore technology. Subjects were compared for the relative abundance and diversity of subgingival microbiota, considering smoking and periodontal condition. The relative abundances of several pathogens were significantly higher among smokers, such as Prevotella denticola and Treponema sp. OMZ 838 in medwakh smokers, Streptococcus mutans and Veillonella dispar in cigarette smokers, Streptococcus sanguinis and Tannerella forsythia in shisha smokers. Subgingival microbiome of smokers was altered even in subjects with no or mild periodontitis, probably making them more prone to severe periodontal diseases. Microbiome profiling can be a useful tool for periodontal risk assessment. Further studies are recommended to investigate the impact of tobacco cessation on periodontal disease progression and oral microbiome.

Objective: Conventional nonsurgical periodontal therapy, i.e., scaling and root planing (SRP), is not sufficient to completely eradicate the microorganisms present in dental plaque biofilm due to the incapability of instruments to reach the inaccessible areas of a tooth with anatomical variations. Hence, to increase the effectiveness of SRP, many adjunctive treatment strategies are proposed, including photodynamic therapy (PDT). Therefore, the purpose of this study was to determine the clinical and microbiological efficacy of PDT using Indocyanine green (ICG) as a novel photosensitizer for the treatment of chronic periodontitis. Materials and Methods: Twenty individuals who fulfilled the eligibility criteria were enrolled for this randomized controlled clinical trial using split-mouth design. Treatment sites from each individual were randomly allocated into two groups: SRP was done for the sites of the control group and an additional session of PDT using ICG was performed for the sites of the test group. Subgingival plaque samples were collected from both the sites and sent for quantitative analysis of Treponema denticola, Porphyromonas gingivalis, and Tannerella forsythia using real-time polymerase chain reaction (RT-PCR) technique. Probing pocket depth (PD), clinical attachment loss (CAL), and count of all the three microorganisms were assessed at baseline and after 3 months. Results: After 3 months, PD and CAL showed statistically significant improvement in the test sites (P < 0.001) compared to the control sites. However, the differences in the microbiological parameters were statistically nonsignificant between the groups. Conclusion: ICG as a photosensitizer may enhance the outcomes of SRP and can be used for PDT for the nonsurgical management of periodontal diseases.

Nitric oxide (NO) produced in the oral cavity is a powerful resource for the human body, especially when NO-syntethase production is not adequate. The role of oral microbiome in determining blood pressure levels has been linked to the active role of some bacterial species involved in the nitro-reducing process. In the present study we investigated the correlation between selected oral microbiome characteristics, nitric oxide (NO) concentration in saliva and their association with hypertension.A case-control study including 48 (25 normotensive and 23 hypertensive subjects), subjects between 50 and 70 years old, was carried out at the dental clinic of an Italian teaching hospital. Characteristics of participants have been evaluated by means of a physical examination, and by an assisted interview. A real-time polymerase chain reaction in samples of saliva and plaque was used to detect Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Tannerella forsythia, Porphyromonas gingivalis, Treponema denticola, Streptococcus mutans, Streptococcus sanguinis, Veillonella dispar and Neisseria subflava as well as total bacterial count. Nitric oxide in saliva was evaluated by the ELISA method.Normotensive subjects, compared with hypertensive subjects, had significantly higher concentration of NO (165.77 ± 61.7 vs 57.49 ± 19.61 μmol/l; p = 0.023), and higher bacterial concentration of the supragingival plaque (4.73E+07 ± 4.33+07 vs 4.02E+07 ± 4.00+07; p = 0.024). Bacterial species, usually associated to good oral health status, such as Neisseria subflava, were significantly more present in normotensive subjects than in hypertensive ones (9090.88 ± 5481.49 vs 4791.35 ± 4349.37; p 0.001). considering the concentration of bacteria as a biomarker of the development of hypertension.The results support the association between hypertension, oral microbiome and salivary nitric oxide, in fact do the results allow us to establish any biomarkers (microbial or biochemical, NO) that allow early therapeutic intervention.

Objectives: The present study was designed to analyse the effect of curcumin on certain periodontopathic pathogens in vitro. Material and Methods: 25% Curcumin was employed to analyze its Minimal Inhibitory Concentration (MIC) potential against the selected micro-organisms.Gram negative oral bacterial strains which included primary colonizers namely, Aggregatebacter actinomycetemcomitans, Streptococcus mitis, Streptococcus sanguis and secondary colonizers which are Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum and Prevotellainter media were cultured using thioglycollate growth medium under anaerobic conditions. Broth microdilution susceptibility test method was employed in order to determine the antimicrobial effectiveness of bacterial responses at growing dilutions of curcumin. After incubation in tubes, the antibacterial activity of curcumin was detected by the lack of turbidity, which indicated the inhibition of bacterial growth. Results: The curcumin MIC values were 12.6 µg/mL, 25 µg/mL, 50 µg/mL, 50 µg/mL, 0.4 µg/mL, 25 µg/mL and 50 µg/mL against P. gingivalis, P. intermedia, T. forsythia, F. nucleatum, A. actinomycetemcomitans, S. sanguis and S. mitis respectively. Conclusions: Curcumin inhibited the growth of all the selected bacterial strains at growing dilutions and is therefore a potent agent against periodontal diseases. There is a need for further in vivo studies to assess the experimental observations on antibacterial effects of curcumin. Keywords: Curcumin, Mean Inhibitory Concentration, Periodontitis, Anti inflammatory, Optical Density

Periodontitis, which is a chronic inflammation caused by biofilm from numerous gram-negative and -positive oral bacterial species between gingiva and tooth, is known to have a poor prognosis. Susceptibility of standard strains (19 strains) and clinical isolates (90 strains) of aerobic and anaerobic oral bacteria, including a recently recovered as novel pathogens for periodontitis called Filifactor alocis, was tested to minocycline (MINO) by using the agar dilution method according to the Clinical and Laboratory Standards Institute. MINO is a well-used therapeutic antibiotic for periodontits. In this study, minimum inhibitory concentrations (MICs) of MINO against Aggregatibacter actinomycetemcomitans (n = 1), Porphyromonas gingivalis (n = 5), Prevotella intermedia (n = 1), Tannerella forsythia (n = 1) and F. alocis (n = 1), were 0.12, ≤0.016–0.03, ≤0.016, 0.03, and 2 μg/mL, respectively. MICs range of MINO against clinical isolates (10 isolates each) Streptococcus intermedius, P. gingivalis, P. intermedia, Fusobacterum nucleatum, Parvimonas micra were 0.06–16, ≤0.016–0.03, ≤0.016–1, ≤0.016–0.12, and ≤0.016–0.25 μg/mL, respectively. These results showed that MINO has superior in vitro activities against to known and recent recovered oral bacteria. Moreover, low prevalence in non-susceptible bacteria was observed to MINO.

The aim was to investigate the detection rates of periodontal bacteria (Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans) and herpesviruses (herpes simplex virus-1 [HSV-1], cytomegalovirus [CMV], and Epstein-Barr virus [EBV]) in different forms and severity of periodontal disease, and to compare them with those in periodontally healthy subjects. One hundred and twenty-nine patients participated in the study: 39 diagnosed with periodontal abscess (PA), 33 with necrotizing ulcerative periodontitis (NUP), 27 with chronic periodontitis (CP), and 30 participants with healthy periodontal tissue represented a healthy control group. All patients with periodontal disease (PA, NUP, and CP) were also divided into two groups according to the severity of their disease: moderate and severe periodontitis. The subgingival samples were collected from the periodontitis active sites and the detection of microorganisms was performed by end-point polymerase chain reaction analyses. The results revealed significantly higher detection rates of P. gingivalis, T. forsythia, and P. intermedia in all three groups of patients with periodontitis than in healthy participants. The highest detection rate of A. actinomycetemcomitans was noticed in CP, which was significantly higher than that in PA, NUP, and healthy control. The occurrence of EBV was significantly higher in NUP than in CP and healthy participants. CMV was detected significantly more frequently in PA and NUP than in CP and healthy participants. Comparisons among healthy participants and patients with moderate and severe periodontitis showed significantly higher detection rates of EBV and CMV in patients with severe forms of periodontitis than in healthy participants and those with moderate periodontitis.

Periodontitis is an irreversible, chronic inflammatory disease where inflammophilic pathogenic microbial communities accumulate in the gingival crevice. Neutrophils are a major component of the innate host response against bacterial challenge, and under homeostatic conditions, their microbicidal functions typically protect the host against periodontitis. However, a number of periodontal pathogens developed survival strategies to evade neutrophil microbicidal functions while promoting inflammation, which provides a source of nutrients for bacterial growth. Research on periodontal pathogens has largely focused on a few established species: Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, and Porphyromonas gingivalis. However, advances in culture‐independent techniques have facilitated the identification of new bacterial species in periodontal lesions, such as the two Gram‐positive anaerobes, Filifactor alocis and Peptoanaerobacter stomatis, whose characterization of pathogenic potential has not been fully described. Additionally, there is not a full understanding of the pathogenic mechanisms used against neutrophils by organisms that are abundant in periodontal lesions. This presents a substantial barrier to the development of new approaches to prevent or ameliorate the disease. In this review, we first summarize the neutrophil functions affected by the established periodontal pathogens listed above, denoting unknown areas that still merit a closer look. Then, we review the literature on neutrophil functions and the emerging periodontal pathogens, F. alocis and P. stomatis, comparing the effects of the emerging microbes to that of established pathogens, and speculate on the contribution of these putative pathogens to the progression of periodontal disease., Neutrophils normally play a critical role in maintaining homeostasis in the oral cavity, but both established and emerging periodontal pathogens evade and manipulate neutrophil functional mechanisms to initiate and maintain a cycle of inflammation that results in periodontitis. Here, we review the effect of established and emerging periodontal pathogens on each neutrophil function and link the aberrant neutrophil phenotype to the pathogenesis of periodontitis.

Background The Gram-negative oral pathogen Tannerella forsythia strictly depends on the external supply of the essential bacterial cell wall sugar N-acetylmuramic acid (MurNAc) for survival because of the lack of the common MurNAc biosynthesis enzymes MurA/MurB. The bacterium thrives in a polymicrobial biofilm consortium and, thus, it is plausible that it procures MurNAc from MurNAc-containing peptidoglycan (PGN) fragments (muropeptides) released from cohabiting bacteria during natural PGN turnover or cell death. There is indirect evidence that in T. forsythia, an AmpG-like permease (Tanf_08365) is involved in cytoplasmic muropeptide uptake. In E. coli, AmpG is specific for the import of N-acetylglucosamine (GlcNAc)-anhydroMurNAc(−peptides) which are common PGN turnover products, with the disaccharide portion as a minimal requirement. Currently, it is unclear which natural, complex MurNAc sources T. forsythia can utilize and which role AmpG plays therein. Results We performed a screen of various putative MurNAc sources for T. forsythia mimicking the situation in the natural habitat and compared bacterial growth and cell morphology of the wild-type and a mutant lacking AmpG (T. forsythia ΔampG). We showed that supernatants of the oral biofilm bacteria Porphyromonas gingivalis and Fusobacterium nucleatum, and of E. coli ΔampG, as well as isolated PGN and defined PGN fragments obtained after enzymatic digestion, namely GlcNAc-anhydroMurNAc(−peptides) and GlcNAc-MurNAc(−peptides), could sustain growth of T. forsythia wild-type, while T. forsythia ΔampG suffered from growth inhibition. In supernatants of T. forsythia ΔampG, the presence of GlcNAc-anhMurNAc and, unexpectedly, also GlcNAc-MurNAc was revealed by tandem mass spectrometry analysis, indicating that both disaccharides are substrates of AmpG. The importance of AmpG in the utilization of PGN fragments as MurNAc source was substantiated by a significant ampG upregulation in T. forsythia cells cultivated with PGN, as determined by quantitative real-time PCR. Further, our results indicate that PGN-degrading amidase, lytic transglycosylase and muramidase activities in a T. forsythia cell extract are involved in PGN scavenging. Conclusion T. forsythia metabolizes intact PGN as well as muropeptides released from various bacteria and the bacterium’s inner membrane transporter AmpG is essential for growth on these MurNAc sources, and, contrary to the situation in E. coli, imports both, GlcNAc-anhMurNAc and GlcNAc-MurNAc fragments.

Periodontitis is attributed to the dental biofilm formation caused by various Red complex organisms are a group of organisms linked with periodontal diseases. Therefore, it is of interest to identify potential targets from the red complex organisms to bind with the herbal compound resveratrol (E - 5 - (4 - hydroxy styryl) benzene 1,3 diol). We report a list of potential proteins having optimal drug like binding features with the herbal agent Resveratrol for further consideration. We used the STITCH v.5 pipeline using VICMPred and VirulentPred tools to identify such targets as potential virulent factors in the red complex organisms. We considered the strains of Porphyromonas gingivalis ATCC 33277, Treponema denticola ATCC 35405 and Tannerella forsythia ATCC 43037 in the red complex pathogens for this analysis. Protein targets in the red complex organisms with optimal binding features with the herbal compound resveratrol were thus identified and reported for further consideration.

OBJECTIVES The aim of this study was to examine the microbial composition of early (after 3 days, D3) and mature biofilms (after 31 days, D31) on materials typically used in implant/abutment buildups. Implant/abutment materials with different surface roughness values (Ra ) were compared to detect differences in the quantity and quality of bacterial composition. MATERIAL AND METHODS Four different materials were investigated: rough implant surface (sand-blasted acid-etched titanium, Ti-p), implant collar (machined titanium, Ti-m), titanium abutment (Ti6Al4V), and zirconium dioxide abutment (ZrO2 ). Fourteen periodontally healthy subjects received mandibular acrylic devices with four disks (one for each material) facing the anterior lingual area. The total bacterial count was analyzed using RT-qPCR. Both presence and proliferation of 20 selected bacterial species were assessed with microarrays. RESULTS The highest mean total cell counts (x108 ± standard deviation) were detected at D3 on ZrO2 (5.63 ± 4.83; Ra = 0.74 µm), followed by Ti-p (4.53 ± 5.00; Ra = 1.87), Ti-m (4.43 ± 9.38; Ra = 0.18 µm), and Ti6Al4V (3.83 ± 3.13; Ra = 0.16 µm). ZrO2 showed significantly higher total bacterial cell counts than Ti-p and Ti-m (p

OBJECTIVE To evaluate microbial and host-derived biomarker changes during experimental peri-implantitis in the Beagle dog. BACKGROUND Limited data exist on the microbial and biomarker changes during progressive bone loss as result of experimental peri-implantitis. METHODS In total, 36 implants (ndogs = 6) were assessed over 3 episodes of ligature-induced peri-implantitis followed by a period of spontaneous progression. Implants with hybrid (H) and completely rough (R) surface designs were used. Clinical and radiographic parameters were recorded at 4 timepoints. Peri-implant sulcus fluid was collected from the buccal and lingual aspects of the implants. The presence of 7 bacterial species and 2 host-derived biomarkers was assessed during the study period. RESULTS Total bacterial counts were significantly correlated with marginal bone loss (MBL) (r = .21; P = .009). Further, Phorphyromonas gulae (Pg) and Tannerella forsythia (Tf) were commonly correlated with MBL, suppuration (SUP) and the sulcular bleeding index scores (mSBI) (P

Objectives Administration of systemic antimicrobials as an adjunct to mechanical treatment of periodontitis and sites with adverse clinical results leads to improved outcomes. This study aimed to assess the antimicrobial susceptibility of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Tannerella forsythia isolated from periodontitis patients to amoxicillin, metronidazole, azithromycin and moxifloxacin. Methods A total of 76 patients diagnosed with generalised periodontitis were included in the study. Subgingival samples were processed by culture. Etest was used to determine susceptibility to amoxicillin, metronidazole, azithromycin and moxifloxacin. Results A total of 141 isolates from 76 patients were evaluated, including 61 P. gingivalis, 43 T. forsythia and 37 A. actinomycetemcomitans. Etest results showed complete susceptibility of A. actinomycetemcomitans, P. gingivalis and T. forsythia to moxifloxacin. However, the isolates presented reduced susceptibility to the other antimicrobial agents investigated. Of the A. actinomycetemcomitans isolates, 70.3%, 40.5% and 89.2% were resistant to amoxicillin, azithromycin and metronidazole, respectively. The P. gingivalis samples showed relatively similar rates of resistance to amoxicillin (24.6%), azithromycin (21.3%) and metronidazole (24.6%). Similarly, 25.6%, 21.0% and 25.6% of the T. forsythia isolates were resistant to amoxicillin, azithromycin, and metronidazole, respectively. Conclusion These findings show that moxifloxacin may be a promising antimicrobial agent against P. gingivalis, T. forsythia and A. actinomycetemcomitans for the treatment of periodontitis. However, amoxicillin, azithromycin and metronidazole were less effective, especially against A. actinomycetemcomitans in vitro.

Glycyrrhizin is a phytocompound which is derived from Glycyrrhiza glabra. It is used in treating the upper respiratory tract disease like cough, bronchitis, laryngitis, sore throat, etc. It has various medicinal uses in rheumatism, peptic ulcers, asthma, allergies, and inflammation. Glycyrrhizin has been reported to possess antibacterial, antiviral, antioxidant, anti inflammatory properties. In view of the above facts, the present in silico study was designed to demonstrate the molecular mechanism underlying the antimicrobial activity of glycyrrhizin against common dental pathogens such as Streptococcus mutans, Porphyromonas gingivalis, Treponema denticola, Enterococcus faecalis and Tannerella forsythia. The STITCH tool was used to identify the drug-protein interaction. The functional class of the protein was deduced using VICMPred, followed by the identification of epitopes on the virulence factors using BepiPred. Further, the subcellular location of the virulence factors were also studied using PSORTb software. The computational analysis performed identified several virulence factors viz., short chain dehydrogenase/reductase family oxidoreductase of Treponema denticola and D-mannonate oxidoreductase of Tannerella forsythia which were found to interact with glycyrrhizin. Interestingly, phosphopyruvate hydratase was found to be the protein present in all the five genera was shown to interact with glycyrrhizin. Thus the present study reveals the target proteins on the dental pathogens which were shown to interact with glycyrrhizin. Furthermore, experimental validation of the results are warranted to provide substantial details on the anti-microbial activity of glycyrrhizin against common dental pathogens.

Objective: Halitosis may be caused by several factors, including various types of food, periodontal diseases, layer of tongue bacteria, and systemicdisorders such as diabetes mellitus (DM), which is a chronic disease that affects the health of periodontal tissue. The present study aimed to assessthe association between the quantity of Tannerella forsythia bacteria and the levels of methyl mercaptan and hydrogen sulfide in periodontitis patientswith type 2 DM (T2DM).Methods: Gingival crevicular fluids (GCF) were collected from 20 patients who were divided into those with periodontitis and who were normoglycemic(n=8); those with periodontitis and T2DM (n=8); and healthy controls (n=4). The patients underwent intraoral periodontal tissue examination,including pocket depth, attachment loss, plaque index, calculus index, and papilla bleeding index. The quantity of T. forsythia bacteria was evaluatedusing quantitative real-time reverse transcription–polymerase chain reaction. The relationship between the number of T. forsythia bacteria and thelevels of methyl mercaptan and hydrogen sulfide in the patients was analyzed by Spearman’s correlative tests.Results: There is a weak and non-significant correlation (p>0.05) between the levels of methyl mercaptan and hydrogen sulfide and the quantity ofT. forsythia in the GCF and tongue coating of periodontitis patients with halitosis regardless of the presence of T2DM.Conclusion: This study suggests no significant relationship between the levels of methyl mercaptan and hydrogen sulfide and the quantity ofT. forsythia in periodontitis patients with halitosis and DM.

BACKGROUND: Periodontitis is a chronic inflammatory disease characterized by Gram-negative bacteria responsible for the degradation of tissues surrounding tooth. Moreover, periopathogens can invade the bloodstream, disseminate and promote cardiovascular disease, such as the link between Porphyromonas gingivalis and atherosclerosis. The aim of this study was to explore the relationship between the severity of periodontitis and of abdominal aortic aneurysm (AAA). METHODS: This cross-sectional study compared patients with stable AAA (n = 30) and patients with unstable AAA (n = 31) based on aortic diameter, growth rate, and eligibility for surgical intervention. Periodontal clinical parameters were recorded as well as the Periodontal Inflamed Surface Area and the Periodontal Index for Risk of Infectiousness (PIRI). Microbiological analyses were performed on saliva and supragingival and subgingival plaque. Quantification of Tannerella forsythia (Tf), Porphyromonas gingivalis (Pg), Aggregatibacter actinomycetemcomitans (Aa), Fusobacterium nucleatum (Fn), and Prevotella intermedia (Pi) was done by quantitative polymerase chain reaction. RESULTS: The two AAA groups were homogeneous for age, sex, and most risk factors except hypertension and chronic obstructive pulmonary disease. Periodontal parameters were comparable but the proportion of patients with high PIRI scores was greater in those with unstable AAA (51.6% versus 23.3%). The probing depth (PD) and the proportion of PD >6 mm were positively correlated with AAA size and thrombus volume. Several associations were found between periopathogens such as Pg and AAA diameters and volumes, but no difference could be evidenced between stable and unstable AAA groups. CONCLUSIONS: Periodontitis was highly prevalent in both stable and unstable AAA patients. Severe and progressive periodontitis (stage IV and grade C) tended to be more frequent in the group of patients with unstable AAA. Moreover, Pg was observed in all the samples (saliva, supragingival, and subgingival plaque) and was correlated with AAA diameters and volumes. The study evidenced potential relationships between periodontitis severity and size of AAA. ispartof: JOURNAL OF PERIODONTOLOGY vol:91 issue:11 pages:1453-1464 ispartof: location:United States status: published

Background Recent advances in the next-generation sequencing (NGS) allowed the metagenomic analyses of DNA from many different environments and sources, including thousands of years old skeletal remains. It has been shown that most of the DNA extracted from ancient samples is microbial. There are several reports demonstrating that the considerable fraction of extracted DNA belonged to the bacteria accompanying the studied individuals before their death. Results In this study we scanned 344 microbiomes from 1000- and 2000- year-old human teeth. The datasets originated from our previous studies on human ancient DNA (aDNA) and on microbial DNA accompanying human remains. We previously noticed that in many samples infection-related species have been identified, among them Tannerella forsythia, one of the most prevalent oral human pathogens. Samples containing sufficient amount of T. forsythia aDNA for a complete genome assembly were selected for thorough analyses. We confirmed that the T. forsythia-containing samples have higher amounts of the periodontitis-associated species than the control samples. Despites, other pathogens-derived aDNA was found in the tested samples it was too fragmented and damaged to allow any reasonable reconstruction of these bacteria genomes. The anthropological examination of ancient skulls from which the T. forsythia-containing samples were obtained revealed the pathogenic alveolar bone loss in tooth areas characteristic for advanced periodontitis. Finally, we analyzed the genetic material of ancient T. forsythia strains. As a result, we assembled four ancient T. forsythia genomes - one 2000- and three 1000- year-old. Their comparison with contemporary T. forsythia genomes revealed a lower genetic diversity within the four ancient strains than within contemporary strains. We also investigated the genes of T. forsythia virulence factors and found that several of them (KLIKK protease and bspA genes) differ significantly between ancient and modern bacteria. Conclusions In summary, we showed that NGS screening of the ancient human microbiome is a valid approach for the identification of disease-associated microbes. Following this protocol, we provided a new set of information on the emergence, evolution and virulence factors of T. forsythia, the member of the oral dysbiotic microbiome.

Three strains representing the previously uncultured human oral Tannerella taxon HMT-286 were recently isolated from the subgingival plaque of a patient with chronic periodontitis. The phenotypic and genetic features of strain SP18_26T were compared to those of the type species of Tannerella , Tannerella forsythia . A genome size of 2.97 Mbp (G+C content 56.5 mol%) was previously reported for SP18_26T, compared to a size of 3.28 Mbp (47.1 mol%) in T. forsythia ATCC 43037T. 16S rRNA gene sequence comparisons also revealed 94.3 % sequence identity with T. forsythia ATCC 43037T. Growth was stimulated by supplementation of media with N-acetyl muramic acid, as seen with T. forsythia , but the cells displayed a distinctive snake-like morphology. Fatty acid methyl ester analysis revealed a profile differing from T. forsythia , chiefly in the amount of 3-OH-16 : 0 (four-fold lower in SP18_26T). Overall, metabolic enzyme activity also differed from T. forsythia , with enzyme activity for indole present, but the complement of glycoside hydrolase enzyme activity was smaller than T. forsythia , for example, lacking sialidase and N-acetyl-β-glucosaminidase – evidence backed up by analysis of its gene content. On the basis of these results, a new species Tannerella serpentiformis is proposed for which the type strain is SP18_26T (=DSM 102894T=JCM 31303T).

Purpose The aims of this study were to examine the salivary microbiota in conditions of periodontal health and disease and to explore microbial changes following nonsurgical periodontal treatment. Methods Non-stimulated saliva samples were collected from 4 periodontally healthy participants at baseline and from 8 patients with chronic periodontitis at baseline and 3 months following nonsurgical periodontal therapy. The V3 and V4 regions of the 16S rRNA gene from the DNA of saliva samples were amplified and sequenced. The salivary microbial compositions of the healthy participants and patients with periodontitis prior to and following nonsurgical treatment of periodontitis were compared based on the relative abundance of various taxa. Results On average, 299 operational taxonomic units were identified in each sample. The phylogenetic diversity in patients with periodontitis was higher than that in healthy participants and decreased following treatment. The abundance of the phylum Spirochaetes and the genus Treponema in patients with periodontitis was 143- and 134-fold higher than in the healthy control group, respectively, but decreased significantly following treatment. The species that were overabundant in the saliva of patients with periodontitis included the Peptostreptococcus stomatis group, Porphyromonas gingivalis, the Fusobacterium nucleatum group, Parvimonas micra, Porphyromonas endodontalis, Filifactor alocis, and Tannerella forsythia. The phylum Actinobacteria, the genus Streptococcaceae_uc, and the species Streptococcus salivarius group were more abundant in healthy participants than in those with periodontitis. There was a trend toward a decrease in disease-associated taxa and an increase in health-associated taxa following treatment. Conclusions Our results revealed differences in the taxa of salivary microbiota between conditions of periodontal health and disease. The taxa found to be associated with health or disease have potential for use as salivary biomarkers for periodontal health or disease., Graphical Abstract

Background and objectives Peri-implantitis remains a challenge for dental implant therapy, and the prognosis of non-surgical therapy for peri-implantitis is unsatisfactory. In order to reveal the impact of non-surgical mechanical debridement therapy on microbial communities, we investigated the subgingival microbial communities of healthy implants and implants with peri-implantitis, both before and after the therapy. Material and methods Subgingival plaques were collected from patients with healthy dental implants (HC; n = 10) and from patients with peri-implantitis (n = 13) before and after non-surgical mechanical debridement therapy. The treatment was conducted using curettes for submucosal debridement followed by irrigation with 0.2% (w/v) chlorhexidine, with re-examination 1 month later. 16S rRNA pyrosequencing was used to analyze the subgingival microbiome, and co-occurrence networks were adopted to explore the interactions between pathogens in the microbial communities. Results A total of 506 955 high-quality reads were generated, and 2222 operational taxonomic units were finally detected using a 97% similarity cutoff, with a mean of 249 ± 69 per sample. The peri-implantitis sites harbored similar microbial communities before and after the treatment, as demonstrated by the microbial diversity, relative abundance, and prevalence of bacteria. Most importantly, the microbial community structures were stable before and after non-surgical therapy based on the microbial diversity and bacterial composition, as well as the interactions between key pathogens, including Enterobacteriaceae, Selenomonas sputigena, Parvimonas, Eubacterium infirmum, Campylobacter gracilis, Tannerella forsythia, and Fusobacterium, which were measured using a co-occurrence network analysis. Periodontal pathogens were also detected in subgingival plaque after the treatment. Distinct microbial communities were found between the healthy and peri-implantitis sites. Conclusion Our results demonstrate that non-surgical mechanical debridement therapy did not significantly affect the subgingival microbial communities in peri-implantitis, and the stable microbial networks created via interactions among pathogens may be responsible for the poor prognosis of peri-implantitis treatment.

Context: Nanoparticles, owing to their smaller size, penetrate regions inaccessible to other delivery systems, such as periodontal pockets. Thus, the present study aimed to comparatively evaluate efficacy of 2% curcumin with nanocarrier and 1% chlorhexidine gel as a local drug delivery (LDD) in the treatment of periodontal pockets. Materials and Methods: Forty-five chronic periodontitis patients with pocket depth 5–7 mm in two or more teeth were selected. Full-mouth scaling and root planing (SRP) was done for all patients followed by random allocation to the three treatment groups, namely SRP group (Group 1), 2% curcumin with nanogel (Group 2), and 1% chlorhexidine gel (Group 3). Clinical parameter assessment and microbiological analysis of subgingival plaque samples for Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), and Tannerella forsythia (Tf) was done at baseline, 21st day, and 45th day. Results: The results showed that when the two LDD agents were used as an adjunct to SRP in chronic periodontitis, there was an improvement in all clinical parameters. Evaluation of microbiological parameters also showed a significant reduction in Aa, Pg, and Tf levels. Comparison of 2% turmeric extract with a nanocarrier system with 1% chlorhexidine gel showed that both the agents had a comparable antibacterial effect on the three selected periodontopathic bacteria. Conclusion: The present study showed that both the LDD agents showed an effective improvement of clinical and microbiologic parameters. 2% curcumin delivered with a nanocarrier system showed results comparable to chlorhexidine gel and hence shows promising future as an LDD agent in the treatment of periodontal pockets.

Periodontal disease is a chronic infectious disease, which is characterized by the damaged dental hard tissue by lactic acid generated by microorganisms after the fermentation of carbohydrates rich diet. The risk of periodontal disease is known to be higher in diabetic patients. We compared the diversity of five commonly occurring dental bacteria including Porphyromonas gingivalis, Tannerella forsythia, Capnocytophaga ochracea, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans in 14 type-2 diabetic patients and equal numbers of healthy controls. The subgingival samples were collected using sterile paper points. We used 16S rRNA sequence specific primers for PCR-based identification of dental bacteria. Our results showed that A. actinomycetemcomitans was completely absent in control subjects but present in 43% of diabetic patients. C. ochracea was highly prevalent in diabetic patients (100%) as compared to controls (28.5%). The frequency of other three bacterial species was also higher in diabetic patients than control subjects. These findings indicate that dental bacteria are highly prevalent in subgingival pockets of diabetic patients. Therefore, proper monitoring of diabetic patients for dental care is important to prevent bacterial growth and its sequela in risky individuals. Further case-control studies using larger sample size would help in validating the association between oral diseases and diabetes. Keywords: Dental bacteria, Identification, PCR, Diabetes

Aim: This study aimed to investigate the association between endodontic clinical signs and symptoms and the presence of Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia employing polymerase chain reaction (PCR). Materials and Methods: Microbial samples were obtained from 60 cases with necrotic pulp with primary teeth infections. DNA extracted from samples were analyzed for endodontic pathogens by using species-specific primers. Results: P. gingivalis/T. denticola were detected in 15 symptomatic teeth associated with periapical lesions. T. forsythia/T. denticola were found in 16 symptomatic teeth associated with pain and swelling. P. gingivalis was detected in 9 teeth which were associated with pain, 2 with tenderness on percussion, and 15 with periapical lesions. Statistically significant associations were found between T. forsythia as well as T. denticola in relation to clinical findings of pain and swelling. (P < 0.05). Red complex bacteria showed no statistical significant association with the presence of signs and symptoms. Conclusion: Prevalence of P. gingivalis, T. denticola, and T. forsythia suggested association of these bacteria with symptomatic infected pulp and periradicular diseases.

Background and Aims: Periodontitis is irreversible plaque-mediated damage to gums and its supporting structures. Plaque is a niche of complex organisms forming biological associations for their attachment and sustenance, forming the basis for periodontal diseases. There is a vast diversity in oral microbiota, depending on the site. Dentition creates natural surfaces and barriers for the diversification of bacteria. For instance, periodontal bacteria differ between supra and subgingival tissues. The plaque mounted on the subgingival area chiefly houses gram-negative anaerobes such as Treponema denticola, Tannerella forsythia, and Porphyromonas gingivalis. The current study aims to compare and contrast the antimicrobial potential of Terminalia arjuna with commercially available mouth rinses against clinical isolates of periodontal bacteria based on the well-diffusion method. Materials and Methods: Preparation of Terminalia arjuna bark extract was done. For the detection of periodontal bacteria, Porphyromonas gingivalis, and Treponema denticola, polymerase chain reaction (PCR) was used. The well-diffusion method was used to test the antimicrobial activity. Results: The aqueous extract of Terminalia arjuna showed minimum zone of inhibition of 23.33 ± 0.577 for Porphyromonas gingivalis and 24.33 ± 0.577 for Treponema denticola while the commercially available mouthwashes M1, M2, M3showed 29.33 ± 0.577, 29.33 ± 0.577, 24.33 ± 0.577, respectively towards Porphyromonas gingivalis and 29.66 ± 0.577, 27.33 ± 0.577, 25.66 ± 0.577, respectively towards Treponema denticola The results depicted nearly equal efficacy of Terminalia arjuna aqueous extract similar to those of commercial mouthwashes against the test bacteria. Conclusion: Antibacterial tests of Terminalia arjuna bark extracts showed promising results even at low concentrations. Hence, it can be an alternative to commercially available mouthwashes, which suffer from having numerous drawbacks ranging from burning sensation while in use to yellowing of teeth surfaces. Herbal medicines are considered to be much safer than other synthetic formulations and possess wide acceptance by people. Hence, this study forms a basis for future studies in this area.

Background/Aim. Periodontal disease is an inflammatory disease that occur in the tissues surrounding the teeth in response to bacterial biofilm accumulation (dental plaque). Among others, Tannerela forsythia (Tf) was recognized as one of the most significant and specific bacterial species in periodontal pocket (?red complex? bacteria). Atherosclerosis is a progressive narrowing of arteries that may lead to occlusion, as a consequence of lipid deposition. It underlies coronary heart disease (80%), as well as myocardial and cerebral infarctions. Increasing evidence over the past decade suggests a link between periodontal disease and atherosclerosis, where Tf can enter the systemic circulation directly or indirectly, and be present in atherosclerotic blood vessels. Therefore, the aim of this study was to detect the presence of Tf in atheromatous plaques obtained from different blood vessels in patients with chronic periodontitis. Methods. Ninety patients (male 61, female 29) with periodontal disease and atherosclerosis [recruited for either carotid artery stenosis requiring endartectomy or percutaneous transluminal coronary angioplasty (PTCA)] were included in this study. Clinical periodontal examinations consisted of plaque index (PI) (according to Silness L?u), gingival index (GI) (according to L?e Silnes), sulcus bleeding index (according to M?hleman-Son) and periodontal probing depth (PPD). Presence of Tf in periodontal pockets and atherosclerotic vessels was detected using polymerase chain reaction (PCR) method with positive control Tf ATCC 43037. Results. Tf was present in subgingival plaques of 68 (75.6%) of the patients, while its presence in atheromatous plaques were registered in 42 (53.3%) of the patients. It was significantly present in coronary blood vessels (41.7%), followed by carotid arteries (35.4%) and a. abdominalis aneurism (12.5%), a. mamaria (8.5%) and a. femoralis (2.1%) while in a. iliaca Tf was not detected at all. Conclusion. The present study suggests strong relationship between periodontal inflammation and atherogenesis; therefore, it should be considered as potential risk factor for atherosclerosis. Accordingly, it would be necessary to control periodontal disease in order to reduce mortality and morbidity associated with atherosclerosis.

Introduction The design of the orthodontic bracket or appliance is 1 of the most important factors for creating retentive areas for biofilm formation. In orthodontics, this would be the first study to compare the microbial level changes in 3 different types of orthodontic appliances using checkerboard DNA-DNA hybridization technique. The purpose of this study was to evaluate and compare the extent of appearance of orange and red microbial complexes in patients undergoing orthodontic treatment using aligners, conventional metallic fixed labial appliances, and lingual fixed appliances. Methods A total of 60 patients, of which 20 patients were undergoing treatment with aligners, 20 patients with labial fixed appliances, and 20 patients with lingual fixed appliances, were included in our study. After 30 days, debonded brackets and rinsed aligners were stored and processed for analysis with checkerboard DNA-DNA hybridization. Results Most bacterial species showed moderate counts, with the exception of Treponema denticola, which showed a higher count in all 3 types of appliances. Fusobacterium nucleatum, Porphyromonas gingivalis, and T denticola were present in a higher percentage in the lingual appliance. Fusobacterium periodontium and Prevotella intermedia were present in a higher percentage in the labial fixed appliance. Campylobacter rectus, Tannerella forsythia, and Prevotella melaninogenica counts were moderate in all 3 appliances, with the first 2 microbes showing slightly higher counts in aligners. The association between all the microorganisms were statistically insignificant, with the exception of F nucleatum, which showed a strong statistically significant association in all 3 types of appliances. Conclusions The microbial contamination in metallic brackets was higher than that of aligners, when used for a month. Lingual fixed appliances showed more microbial contamination than labial fixed appliances followed by aligners.

Emerging evidence has shown the potential of oral microbiota as a noninvasive diagnostic tool in gastrointestinal (GI) cancer. PubMed, Web of Science, and Embase were systematically searched for eligible studies published until May 31, 2019. Of the 17 included studies published between 2011 and 2019, five kinds of GI cancer, including colorectal cancer (n=6), pancreatic cancer (n=5), gastric cancer (n=4), esophageal cancer (n=2) and liver cancer (n=1), were reported. Generally, the diagnostic performance of the multi-bacteria model for GI cancer was strong with the best area under the receiver operator characteristic curve (AUC) exceeding 0.90, but only one study had a validation phase. Pathogens involved in periodontal disease, such as Porphyromonas gingivalis and Tannerella forsythia, were linked to various kinds of GI cancer. Besides, more oral bacteria significantly differed between cases with upper digestive cancer and healthy controls when compared to colorectal cancer (the most common form of lower digestive cancer), probably indicating a different mechanism due to anatomical and physiological differences in the digestive tract. Oral microbiota changes were associated with risk of various kinds of GI cancer, which could be considered as a potential tool for early prediction and prevention of GI cancer, but validation based on a large population, reproducible protocols for oral microbiota research and oral-gut microbiota transmission patterns are required to be resolved in further studies.

The Gram-negative periodontal pathogen Tannerella forsythia is inherently auxotrophic for N-acetylmuramic acid (MurNAc), which is an essential carbohydrate constituent of the peptidoglycan (PGN) of the bacterial cell wall. Thus, to build up its cell wall, T. forsythia strictly depends on the salvage of exogenous MurNAc or sources of MurNAc, such as polymeric or fragmentary PGN, derived from cohabiting bacteria within the oral microbiome. In our effort to elucidate how T. forsythia satisfies its demand for MurNAc, we recognized that the organism possesses three putative orthologs of the exo-β-N-acetylmuramidase BsNamZ from Bacillus subtilis, which cleaves non-reducing end, terminal MurNAc entities from the artificial substrate pNP-MurNAc and the naturally-occurring disaccharide substrate MurNAc-β-1,4-N-acetylglucosamine (GlcNAc). TfNamZ1 and TfNamZ2 were successfully purified as soluble, pure recombinant His6-fusions and characterized as exo-lytic β-N-acetylmuramidases with distinct substrate specificities. The activity of TfNamZ1 was considerably lower compared to TfNamZ2 and BsNamZ, in the cleavage of pNP-MurNAc and MurNAc-GlcNAc. When peptide-free PGN glycans were used as substrates, we revealed striking differences in the specificity and mode of action of these enzymes, as analyzed by mass spectrometry. TfNamZ1, but not TfNamZ2 or BsNamZ, released GlcNAc-MurNAc disaccharides from these glycans. In addition, glucosamine (GlcN)-MurNAc disaccharides were generated when partially N-deacetylated PGN glycans from B. subtilis 168 were applied. This characterizes TfNamZ1 as a unique disaccharide-forming exo-lytic β-N-acetylmuramidase (exo-disaccharidase), and, TfNamZ2 and BsNamZ as sole MurNAc monosaccharide-lytic exo-β-N-acetylmuramidases.IMPORTANCETwo exo-β-N-acetylmuramidases from T. forsythia belonging to glycosidase family GH171 (www.cazy.org) were shown to differ in their activities, thus revealing a functional diversity within this family: NamZ1 releases disaccharides (GlcNAc-MurNAc/GlcN-MurNAc) from the non-reducing ends of PGN glycans, whereas NamZ2 releases terminal MurNAc monosaccharides. This work provides a better understanding of how T. forsythia may acquire the essential growth factor MurNAc by the salvage of PGN from cohabiting bacteria in the oral microbiome, which may pave avenues for the development of anti-periodontal drugs. On a broad scale, our study indicates that the utilization of PGN as a nutrient source, involving exo-lytic N-acetylmuramidases with different modes of action, appears to be a general feature of bacteria, particularly among the phylum Bacteroidetes.

IgA nephropathy (IgAN) has been considered to have a relationship with infection in the tonsil, because IgAN patients often manifest macro hematuria just after tonsillitis. In terms of oral-area infection, the red complex of periodontal bacteria (Porphyromonas gingivalis (P. gingivalis), Treponema denticol (T. denticola) and Tannerella forsythia (T. forsythia)) is important, but the relationship between these bacteria and IgAN remains unknown. In this study, the prevalence of the red complex of periodontal bacteria in tonsil was compared between IgAN and tonsillitis patients. The pathogenicity of IgAN induced by P. gingivalis was confirmed by the mice model treated with this bacterium. The prevalence of P. gingivalis and T. forsythia in IgAN patients was significantly higher than that in tonsillitis patients (p < 0.001 and p < 0.05, respectively). A total of 92% of tonsillitis patients were free from red complex bacteria, while only 48% of IgAN patients had any of these bacteria. Nasal administration of P. gingivalis in mice caused mesangial proliferation (p < 0.05 at days 28a nd 42; p < 0.01 at days 14 and 56) and IgA deposition (p < 0.001 at day 42 and 56 after administration). Scanning-electron-microscopic observation revealed that a high-density Electron-Dense Deposit was widely distributed in the mesangial region in the mice kidneys treated with P. gingivalis. These findings suggest that P. gingivalis is involved in the pathogenesis of IgAN.

Antibiotics : open access journal 10(12), 1464 (2021). doi:10.3390/antibiotics10121464 special issue: "Special Issue "Antibacterial Treatment in Periodontal and Endodontic Therapy" / Special Issue Editors: Prof. Dr. Andreas Braun, Guest Editor; Prof. Dr. Felix Krause; Guest Editor", Published by MDPI, Basel

The worldwide increase in nonalcoholic fatty liver disease (NAFLD) is a major public health problem. Obesity and diabetes are risk factors for NAFLD and the development of liver fibrosis is a risk factor for liver cancer. Periodontal disease bacteria can also exacerbate NAFLD. We previously reported that amazake, a traditional Japanese fermented food, improves the quality of life (QOL) of patients with liver cirrhosis. In this study, we investigated the effect of amazake intake on NAFLD patients with periodontal disease. Ten patients (mean age: 57.1 ± 19.2 years) consumed 100 g of amazake daily for 60 days. On days 0 and 60, their body mass index (BMI), body fat percentage, serum biochemical parameters, periodontal disease bacteria in saliva, and ten visual analog scales (VASs), namely, sense of abdomen distension, edema, fatigue, muscle cramps, loss of appetite, taste disorder, constipation, diarrhea, depression, and sleep disorder, were measured. For periodontal bacteria, the numbers of six types of bacteria in saliva (Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Fusobacterium necleatum) and P. gingivalis-specific fimA genotype were determined. After 60 days of amazake consumption, eosinophils (p &lt, 0.05), immune reactive insulin (IRI) (p &lt, 0.01), and HOMA-IR (p &lt, 0.05) had significantly increased and tumor necrosis factor α (TNFα) (p &lt, 0.01), muscle cramps (p &lt, 0.05), and depression (p &lt, 0.05) had significantly decreased. All subjective symptoms improved after amazake intake. No change was observed in the periodontal bacteria. In conclusion, amazake significantly decreased TNFα and improved the QOL of the patients with NAFLD and periodontitis. However, caution should be exercised because amazake, which is manufactured using techniques that lead to concentrations of glucose from the saccharification of rice starch, may worsen glucose metabolism in NAFLD patients. Amazake may be an effective food for improving the symptoms of a fatty liver if energy intake is regulated.

Numerous bacterial species participate in the shift of the oral microbiome from beneficial to dysbiotic. The biggest challenge lying ahead of microbiologists, immunologists and dentists is the fact that the bacterial species act differently, although usually synergistically, on the host immune cells, including neutrophils, and on the surrounding tissues, making the investigation of single factors challenging. As biofilm is a complex community, the members interact with each other, which can be a key issue in future studies designed to develop effective treatments. To understand how a patient gets to the stage of the late-onset (previously termed chronic) periodontitis or develops other, in some cases life-threatening, diseases, it is crucial to identify the microbial composition of the biofilm and the mechanisms behind its pathogenicity. The members of the red complex (Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia) have long been associated as the cause of periodontitis and stayed in the focus of research. However, novel techniques, such as 16S clonal analysis, demonstrated that the oral microbiome diversity is greater than ever expected and it opened a new era in periodontal research. This review aims to summarize the current knowledge concerning bacterial participation beyond P. gingivalis and the red complex in periodontal inflammation mediated by neutrophils and to spread awareness about the associated diseases and pathological conditions.