Rate of cultivable subgingival periodontopathogenic bacteria in chronic periodontitis

An Anaerobic Culture Study to Assess the Prevalence of Porphyromonas gingivalis in Periodontal Disease Incidences Among Adults

Introduction Periodontitis is a complex condition influenced by various factors involving interactions between the host and bacterial plaque. Porphyromonas gingivalis, an anaerobic gram-negative bacterium, is commonly linked with periodontal disease. Aim This study aimed to examine the occurrence of P. gingivalis in individuals diagnosed with chronic periodontitis (CP) compared to those who show no clinical indications of periodontal disease. Methodology Patients diagnosed with CP (including both severe and moderate cases) and individuals without any signs of periodontal disease were recruited for this study. Samples were collected from the gingival pockets using curettes and were subsequently subjected to anaerobic culturing. Results A group of 30 patients, divided into moderate and severe CP, along with 30 healthy individuals serving as controls, were examined. In individuals with CP, P. gingivalis was found in 23 (78%) of cases, while in healthy individuals, the prevalence was 10 (34%). The presence of P. gingivalis was notably higher in those with periodontal diseases compared to healthy subjects, with rates of 23 (78%) vs. 10 (34%), respectively. Conclusion P. gingivalis is frequently found in individuals with periodontal diseases as well as in those without such conditions, albeit in smaller quantities. Consequently, the existence of P. gingivalis raises the probability of developing periodontal disease and may be regarded as a notable potential contributor to its initiation.

Prevotella: An insight into its characteristics and associated virulence factors

Prevotella species, a gram-negative obligate anaerobe, is commonly associated with human infections such as dental caries and periodontitis, as well as other conditions such as chronic osteomyelitis, bite-related infections, rheumatoid arthritis and intestinal diseases like ulcerative colitis. This generally harmless commensal possesses virulence factors such as adhesins, hemolysins, secretion systems exopolysaccharide, LPS, proteases, quorum sensing molecules and antibiotic resistance to evolve into a well-adapted pathogen capable of causing successful infection and proliferation in the host tissue. This review describes several of these virulence factors and their advantage to Prevotella spp. in causing inflammatory diseases like periodontitis. In addition, using genome analysis of Prevotella reference strains, we examined other putative virulence determinants which can provide insights as biomarkers and be the targets for effective interventions in Prevotella related diseases like periodontitis.

Aggregatibacter actinomycetemcomitans as the Aetiological Cause of Rheumatoid Arthritis: What Are the Unsolved Puzzles?

Leukotoxin A (LtxA) is the major virulence factor of an oral bacterium known as Aggregatibacter actinomycetemcomitans (Aa). LtxA is associated with elevated levels of anti-citrullinated protein antibodies (ACPA) in rheumatoid arthritis (RA) patients. LtxA targets leukocytes and triggers an influx of extracellular calcium into cytosol. The current proposed model of LtxA-mediated hypercitrullination involves the dysregulated activation of peptidylarginine deiminase (PAD) enzymes to citrullinate proteins, the release of hypercitrullinated proteins through cell death, and the production of autoantigens recognized by ACPA. Although model-based evidence is yet to be established, its interaction with the host’s immune system sparked interest in the role of LtxA in RA. The first part of this review summarizes the current knowledge of Aa and LtxA. The next part highlights the findings of previous studies on the association of Aa or LtxA with RA aetiology. Finally, we discuss the unresolved aspects of the proposed link between LtxA of Aa and RA.

Periodontopathogens: a new view. Systematic review. Part 2

Relevance. The modern view of periodontitis as a dysbiotic disease that occurs as a result of changes in the microbial composition of the subgingival region is considered in a systematic review.

Purpose. To study a new paradigm of development of generalized periodontitis.

Materials and methods. Randomized controlled trials (RCTS) were selected for the study, including cluster RCTS, controlled (non-randomized) microbiological and clinical studies of the oral microbiome in adult patients with generalized periodontitis over the past 10 years.

Results. The transition from a symbiotic microflora to a dysbiotic pathogenic community triggers the host's inflammatory response, which contributes to the development of periodontal diseases. Modern ideas about periodontal pathogenic bacteria dictate new requirements for the treatment of periodontal diseases. The second part of the review examines the microbial profiles of periodontal disease in various nosological forms, the mechanisms of the immune response and approaches to the treatment of periodontal disease from the perspective of biofilm infection.

Conclusions. As follows from modern literature periodontitis is to a certain extent caused by the transition from a harmonious symbiotic bacterial community to a dysbiotic one. Recent scientific studies have shown that not single microorganism is not able to cause disease but the microbial community as a whole leads to the development of pathology.

Research of the potential biomarkers in vaginal microbiome for persistent high-risk human papillomavirus infection

Background

Vaginal dysbiosis may paly role in increased risk of human papillomavirus (HPV) infection. This study aims to explore potential vaginal microbiome biomarkers, to predict persistent high-risk HPV (HR-HPV) infection and cervical intraepithelial neoplasia (CIN) 2+, and to find novel treatment targets for HPV infection.

Methods

A total of 329 women aged 20-69 were enrolled in this study, including 59 with cervical persistent HPV infection irrespective of cytology status (group A), 139 with incident HPV infection (group B), and 131 without HPV infection (group C). Vaginal microbiome composition was determined by sequencing of barcoded 16S rDNA gene fragments (V4) on Illumina HiSeq2500.

Results

In genus level, the relative abundance of Prevotella, Porphyromonas and Enterococcus were significantly the highest in group A, while Bacteroides was the lowest in group A. In species level, we found the relative abundance of Prevotella bivia, Enterococcus durans and Porphyromonas uenonis were the highest in group A while Lactobacillus iners was significantly under-represented in group A than the other two, and Prevotella disiens was over-represented in group C than the other two groups.

Conclusions

A predominance of Prevotella bivia, Enterococcus durans and Porphyromonas uenonis with a concomitant paucity of Lactobacillus iners and Prevotella disiens may relate to HPV persistent infection. Furthermore, the relative abundance of Prevotella bivia being over 0.05554% with Prevotella disiens being under 0.02196% may be a good predictor for appearance CIN2+ for those diagnosed with the other 12 types of HR-HPV persistent infection but normal ThinPrep cytology test (TCT) testing. The exact molecular mechanism of the vaginal microbiome in the course of persistent HR-HPV infection and cervical neoplasia should be further explored. Future research should include intervention of vaginal microbiome composition to reverse the course of HR-HPV infection and the natural history of cervical neoplasia.

Antimicrobial Effect of Platelet-Rich Plasma against Porphyromonas gingivalis

Aim

The aim of our study was to evaluate whether there was a difference in antimicrobial effect between the PRP of healthy volunteers and that of patients with chronic periodontitis against P. gingivalis, which was fresh cultured from subgingival plaque.

Methods

Subgingival plaque of patients with moderate and severe chronic periodontitis was collected to isolate P. gingivalis. The PRP of four individuals with healthy periodontium and four patients with moderate and severe periodontitis were collected with a specific kit using a two-centrifuge procedure, and then, the antibacterial properties against P. gingivalis were tested, through their minimum inhibitory concentration (MIC), adhesion resistance assay, and biofilm susceptibility assay.

Results

P. gingivalis was successfully isolated from the subgingival plaque of the 21st patient. The round, smooth, and black colony appeared in the agar disk after 7–10 days of incubation under anaerobic conditions. Bacterial identification was performed by MALDI-TOF and confirmed by PCR. All PRP samples tested showed the ability to inhibit P. gingivalis growth. The MIC value (expressed as fraction of PRP) was 1/2, and PRP prevented P. gingivalis attachment on the disk surface. However, PRP did not have a strong effect on the suppression of P. gingivalis biofilm.

Conclusion

PRP of individuals with healthy periodontium and chronic periodontitis patients showed antibacterial properties against P. gingivalis. This material can become an adjunct to periodontal treatment.

Molecular-level evaluation of selected periodontal pathogens from subgingival regions in canines and humans with periodontal disease

Dogs commonly serve as a model for various human conditions, including periodontal diseases. The aim of this study was to identify the anaerobic bacteria that colonize the subgingival areas in dogs and humans by using rapid real-time polymerase chain reaction (RT-PCR)-based tests and to compare the results obtained in each species. Bacterial microflora evaluations, both quantitative and qualitative, were performed by applying ready-made tests on twelve dogs and twelve humans. Five samples were collected from each subject's deepest gingival pockets and joined to form a collective sample. The results of the study revealed interspecies similarities in the prevalences of Porphyromonas (P.) gingivalis, Treponema denticola, Tannerella forsythia, and Fusobacterium nucleatum. Red complex bacteria comprised the largest portion of the studied bacterial complexes in all study groups, with P. gingivalis being the most commonly isolated bacterium. The results show similarities in the prevalence of bacterial microflora in dogs and humans. Microbiological analysis of gingival pockets by using rapid real-time PCR-based tests in clinical practice, both veterinary and human, can facilitate the choice of appropriate pharmacological treatment and can provide a basis for subsequent verification of the treatment's effectiveness.

Evaluation of antimicrobial action of Carie Care™ and Papacarie Duo™ on Aggregatibacter actinomycetemcomitans a major periodontal pathogen using polymerase chain reaction

Background:

In the present scenario, we are made available with chemomechanical caries removal system containing a natural proteolytic enzyme for the ease in the excavation of infected dentine. The additive action for these agents is providing antimicrobial and anti-inflammatory properties.

Aim:

This study was undertaken for assessing the action of Carie Care™ and Papacarie Duo™ on Aggregatibacter actinomycetemcomitans.

Materials and Methods:

The samples were collected for cultivation of the periodontal pathogen from the clinical periodontal pockets using sterile paper points. The samples cultured under suitable conditions were analyzed with quantitative polymerase chain reaction targeting 16s r-DNA. The samples were divided into three groups namely, Group A: Control, Group B: With Papacarie Duo, Group C: With Carie Care. The pathogen inoculums plugs were inserted in the petri dishes containing chemically defined medium and the experimental gels at different concentrations and were incubated under optimal conditions. The inhibition of growth of the pathogen was studied visually.

Results:

There was visual inhibition of growth for Group B and C and also exhibited a dose-dependent effect also.

Conclusion:

Based on the results of the present study, Carie Care™ gel demonstrated better antimicrobial action against A. actinomycetemcomitans which is a major periodontal disease causing pathogen.

Sonication assisted microbiological diagnosis of implant-related infection caused by Prevotella disiens and Staphylococcus epidermidis in a patient with cranioplasty

Background

Infections present a major complication of cranioplasty procedures and in many cases removal of the implant material becomes a necessity. Sonication of the artificial implant material has been used during the last years, in order to facilitate better diagnosis of these infections, nevertheless its use in cranial implant infections is still limited.

Case presentation

A case of a 63-year-old Caucasian male patient who underwent a decompressive craniectomy, due to intracranial hemorrhage, and a consequent cranioplasty using an autogenic bone flap fixed by titanium clamps, is reported. After three unsuccessful cranioplasty efforts to repair a persistent skin defect, removing the bone flap and the titanium clamps was a necessity. Tissue and bone cultures were unable to reveal any microorganism whilst sonication of the removed titanium clamps and consequent culture of the resulting sonication liquid yielded Prevotella disiens and Staphylococcus epidermidis. The patient was treated with daptomycin and metronidazole until discharge and the skin defect was successfully repaired.

Conclusion

The present case report indicates that the use of the sonication procedure assisted the microbiological diagnosis. This is the first known neurosurgical case of the implementation of the sonication procedure.

Microbial flora in chronic periodontitis: study at a tertiary health care center from north karnataka

Background and Objective:

Periodontitis is a major public health problem in India with a prevalence of 60–80%. If untreated it acts as a risk factor for systemic diseases. Data on anaerobic periodontal microflora in the Indian population is very scarce. Hence, this study was undertaken to know the nature of oral microbiota in chronic periodontitis in this region of India and also the semiquantitative study in pre- and post-treatment group and to determine antibiotic susceptibility pattern for aerobic isolates.

Materials and Methods:

The present study was conducted on 60 cases. Material was collected from the subgingival pockets in patients with chronic periodontitis attending the Periodontology, Outpatient Department. Clinical samples were transported to the laboratory in fluid thioglycollate medium. Initially Gram's stain and Fontana stains were done. Aerobic, anaerobic, and microaerophilic culture were put up. Antibiotic sensitivity test was done for aerobic isolates.

Results:

Sixty samples yielded 121 isolates of which 78.34% were polymicrobial, 11.66% were monomicrobial and oral commensals were grown in 10% cases. Out of 121 isolates 91.74% were anaerobic, 7.43% were aerobic and 0.83% were microaerophilic. Fusobacterium species was the most common isolate among anaerobes. Using “paired t-test” “P” value was significant indicating significant reduction in colony count after phase-I periodontal therapy.

Conclusion:

This study has shown that anaerobic bacteria are important cause of chronic periodontitis, along with aerobes and microaerophilic organisms. Fusobacterium spp, Bacteroides fragilis, Porphyromonas spp and Prevotella intermedia are the most common anaerobic pathogens. Bacterial culture methods are still economical and gold standard.

Lessons learned and unlearned in periodontal microbiology

Periodontal diseases are initiated by bacterial species living in polymicrobial biofilms at or below the gingival margin and progress largely as a result of the inflammation elicited by specific subgingival species. In the past few decades, efforts to understand the periodontal microbiota have led to an exponential increase in information about biofilms associated with periodontal health and disease. In fact, the oral microbiota is one of the best-characterized microbiomes that colonize the human body. Despite this increased knowledge, one has to ask if our fundamental concepts of the etiology and pathogenesis of periodontal diseases have really changed. In this article we will review how our comprehension of the structure and function of the subgingival microbiota has evolved over the years in search of lessons learned and unlearned in periodontal microbiology. More specifically, this review focuses on: (i) how the data obtained through molecular techniques have impacted our knowledge of the etiology of periodontal infections; (ii) the potential role of viruses in the etiopathogenesis of periodontal diseases; (iii) how concepts of microbial ecology have expanded our understanding of host-microbe interactions that might lead to periodontal diseases; (iv) the role of inflammation in the pathogenesis of periodontal diseases; and (v) the impact of these evolving concepts on therapeutic and preventive strategies to periodontal infections. We will conclude by reviewing how novel systems-biology approaches promise to unravel new details of the pathogenesis of periodontal diseases and hopefully lead to a better understanding of their mechanisms.

Evaluation of subgingival microflora in all ceramic restorations with subgingival heavy chamfer finish lines

Microbial colonization in the gingival sulci of abutment teeth receiving all ceramic retainers with subgingival margins need to be studied to assess the prognosis of periodontal health, which determine the eventual success of fixed partial dentures. This prospective observational study was done to evaluate the quantitative alteration in the microbial flora in the gingival sulci of abutment teeth adjacent to the edentulous space prior and after receiving all ceramic retainers over varying time intervals of 1 week, 1 month and 2 months respectively. Twenty, healthy partially edentulous patients, aged 20-50 years with single missing central incisor were selected for this prospective observational study and their microbial samples were collected from the gingival sulci of abutments adjacent to edentulous space with sterile paper points and cultured and the estimated values for microflora served as controls. The same abutments were prepared to receive all ceramic retainers with subgingival heavy chamfer marginal finish lines. The patients were recalled after 1 week, 1 month, 2 months intervals during which the collected subgingival microbial samples were cultured and the corresponding quantitative microbial alteration in the restored gingival sulci was recorded. The obtained data was statistically analysed using the student t test and repeated analysis of variance test. The results of the study inferred student t test expressed a statistically significant (p < 0.001) progressive increase in gingival sulcular microbial colonisation in the abutment teeth before [M = 2.52 ± SD 1.21(10(6)) CFU/ml] and after receiving all ceramic retainers over varying time intervals of 1 week [M = 3.25 ± SD 1.21(10(6)) CFU/ml], 1 month [M = 4.64 ± SD 1.13(10(6)) CFU/ml] and 2 months [M = 4.75 ± SD 1.16(10(6)) CFU/ml] respectively. The result of repeated analysis of variance test inferred that there was a statistically significant difference (p < 0.001) in the subgingival microfloral count between the pre operative and post operative samples at 1 week, 1 month and 2 months. Subgingivally placed all-ceramic retainers with heavy chamfer finish lines in the abutment teeth demonstrated a statistically significant increase in sulcular microbial colonization over varying time intervals of 1 week, 1 month and 2 months respectively and this may affect periodontal health of abutment teeth progressively.

Identification of oral bacteria by 16S rRNA gene analysis in elderly persons requiring nursing care

After incubation of saliva from 58 semi-bedridden elderly persons, the cultures were identified based on the 16S rRNA gene base sequence to compare the identification by the conventional culture method. As a result, the 16S rRNA gene base sequence of 198 strains identified by the culture method showed 98.5% or more homology in some of the Human Oral Microbiome database, and the identification of bacterial species and genus was possible. When an organism identified by the 16S rRNA gene sequencing method was compared with that by the culture method, the concordance rates were 54.5% at the genus level and 35.9% at the species level. Streptococcus mitis strains most frequently isolated from saliva that were identified by the culture method were identified as the same species by the 16S rRNA gene sequencing method (32/35), and all the 11 Streptococcus salivarius strains identified by the culture method were identified as the same species by the 16S rRNA gene sequencing method. All the strains identified as Streptococcus anginosus group by the culture method and 8 of the 9 strains identified as Prevotella species by the culture method were identified as the same group and genus by the 16S rRNA gene sequencing method. When an oral microbial flora test with saliva samples from elderly persons is performed, the 16S rRNA gene sequence identification enables us to identify major indigenous bacteria and pathogenic bacteria and is considered useful as a means of supplementing the conventional culture method.

Anaerobic Bacteria in Subjects with Chronic Periodontitis and In Periodontal Health

The aim of the present study was to look at the frequency of strict anaerobic bacteria in patients with chronic periodontitis and healthy subjects without periodontal destruction. Hundred patients with chronic periodontitis and hundred healthy subjects with no clinical signs of periodontal disease were included in the study. Sterile paper points were used for sample collection from the deepest pocket site in case of periodontitis patients. The samples were cultured under anaerobic conditions and characterized to species level by conventional biochemical tests. Anaerobes were isolated in 83% of periodontitis cases and 62% of healthy subjects. Porphyromonas gingivalis (48%), Fusobacterium nucleatum (24%), Peptostreptococcus micros (23%) and Prevotella spp. (26%) were the commonest anaerobes isolated in periodontitis patients, while Peptostreptococcus micros (36%), Prevotella spp. (8%), Veillonella (10%) and Actinomyces viscosus (12%) were frequently detected in the control group. Data shows the diversity of anaerobic bacteria in chronic periodontitis.

Recovery of putative pathogens from paper point sampling at different depths of periodontal lesions

Background

The aim of this study was to compare the recovery of three putative periodontal pathogens from periodontal lesions in samples using paper points inserted to different depths of the lesions.

Methods

Twenty 6–8 mm deep periodontal lesions with bleeding on probing were studied. Microbial samples were obtained using paper points inserted to three different depths of the lesions: orifice of lesion; 2 mm into the lesion; and to the base of lesion. Culturing was used for recovery and identification of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia.

Results

The recovery of each of the three putative periodontal pathogens was similar following sampling at the various depths of the lesions.

Conclusions

The findings may be explained by the fact that the paper points become saturated as they pass through the orifice of the lesion. Absorption of microorganisms will therefore primarily occur at the orifice. It is also conceivable that the pathogens may be present in similar proportions throughout the various depths of the periodontal lesions.

Influence of previous antimicrobial therapy on oral carriage of beta-lactamase producing Capnocytophaga isolates

AIM

In order to assess the prevalence of beta-lactamase producing oral bacteria in childhood, the influence of different parameters on the oral carriage of Capnocytophaga was studied in a specific population of children with cancer. The examined parameters included clinical observation of oropharyngeal mucosa, type of malignant disease and intake of chemotherapy and antimicrobial treatment.

METHODS

The gingival and mucosal status of the patients was recorded before each sampling procedure. Samples were collected by oropharyngeal swabbing in children with leukaemia or other oncological diseases for isolation of Capnocytophaga strains.

RESULTS

Capnocytophaga strains were more often isolated in samples from children with oncological diseases (71%) other than leukaemia (57%). Concomitant chemotherapy had no influence on oral Capnocytophaga carriage. A significant decrease of the prevalence of Capnocytophaga strains isolated was observed in children who received antimicrobial treatment within 8 days before the sampling procedure (15.5% vs. 28%). But, the incidence of beta-lactamase-producing strains was not linked to previous antimicrobial treatments.

CONCLUSION

Oral carriage of Capnocytophaga strains can be linked to haematological disease and previous antibiotherapy, but results did not confirm that beta-lactamase treatments exert a selective pressure. Other factors might be involved in emerging for oral beta-lactamase-producing Capnocytophaga strains.

Association of Eubacterium nodatum and Treponema denticola with human periodontitis lesions

BACKGROUND

The purpose of the present investigation was to compare the levels, proportions and percentage of sites colonized by 40 bacterial species in subgingival plaque samples from periodontally healthy subjects and patients with chronic periodontitis to seek possible pathogens other than the consensus pathogens Porphyromonas gingivalis and Tannerella forsythia.

METHOD

Subgingival plaque samples were taken from the mesial aspect of each tooth in 635 subjects with chronic periodontitis and 189 periodontally healthy subjects. The samples were individually analyzed for their content of 40 bacterial species using checkerboard DNA-DNA hybridization (total samples = 21,832). Mean counts, % DNA probe counts and percentage of sites colonized at >10(5) were determined for each species in each subject and then averaged in each clinical group. Significance of difference between groups was determined using the Mann-Whitney test. Association between combinations of species and periodontal status was examined by stepwise logistic regression analysis. Analyses were repeated using a subset of subjects from both clinical groups who had proportions of P. gingivalis plus T. forsythia less than the median (4.42%) found in periodontally healthy subjects. All analyses were adjusted for multiple comparisons.

RESULTS

For the 824 subjects the consensus pathogens P. gingivalis and T. forsythia as well as Eubacterium nodatum and Treponema denticola had significantly higher mean counts, proportions and percentage of sites colonized in samples from subjects with periodontitis than from periodontally healthy subjects. There were significantly more Capnocytophaga gingivalis, Streptococcus gordonii and Veillonella parvula in periodontally healthy subjects. E. nodatum, T. denticola, Streptococcus oralis, Streptococcus intermedius, Fusobacterium nucleatum ssp. vincentii all had higher counts and proportions in diseased than healthy subjects who had low proportions of P. gingivalis and T. forsythia. Logistic regression analysis indicated that the same species groups were associated with disease status after adjusting for the proportions of the other species.

CONCLUSIONS

This investigation confirmed the strong association of P. gingivalis and T. forsythia with chronic periodontitis and emphasized a strong association of E. nodatum and T. denticola with periodontitis whether in the presence or absence of high levels of the consensus pathogens. Other species, including S. oralis, Eikenella corrodens, S. intermedius and F. nucleatum ssp. vincentii, were associated with disease when P. gingivalis and T. forsythia were present in low proportions.