Membrane vesicles from periodontal pathogens and their potential roles in periodontal disease and systemic illnesses.

Periodontium is an ordered ecological system where a dynamic equilibrium exists between oral microorganisms and the host defense system, and periodontal disease occurs whenever the balance is broken. Periodontal pathogens mainly include gram-negative anaerobic bacteria and emerging gram-positive microbes, which have a large variety of virulence factors and influence disease initiation and progression. Recently, different types of bacterial membrane vesicles (MVs), formed by bubbling of membrane materials from living cells or in conditions of endolysin-triggered cell death, have gained interests as a novel virulence factor for periodontopathogens. MVs load multiple sorted cargo molecules, such as proteins, lipids, and genetic materials, and actively participate in toxin transport, signal delivery, and periodontal disease pathogenesis. Since periodontitis is recognized as a risk factor for many systemic diseases, periodontal MVs could work as a bridge for periodontal diseases and systemic illnesses. Furthermore, MVs with unique nature and advantages are promising candidates as vaccines and drug delivery vehicles. In this review, we provided an overview of different types and compositions of periodontal MVs, described their involvements in the pathogenesis of periodontitis and several general diseases, and discussed potential applications of periodontal MVs in vaccination and drug delivery.

Inter- and intra-test agreement of three commercially available molecular diagnostic tests for the identification of periodontal pathogens.

OBJECTIVE: The aim of the study was to compare the agreement and reproducibility of three test kits (IAI Pado Test 4⋅5®, micro-IDent®, and Carpegen® Perio Diagnostik) regarding the detection of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Aggregatibacter actinomycetemcomitans. MATERIALS AND METHODS: Periodontal plaque samples from 20 patients suffering from severe chronic or aggressive periodontitis were split into two identical batches. Samples of batch 1 were evaluated immediately. Samples of batch 2 were analyzed after a storage period of 2 weeks at 4 °C. RESULTS: The conformity of results obtained by the evaluated test kits as well as the concordant detection rate of periodontopathogens proved to be low. The agreement of the detection rate depends on the chosen test kit. The intra-test reproducibility of the qualitative analysis of identical plaque samples was perfect only for Carpegen® Perio Diagnostik. The quantitative analysis of the results expressed as n-fold difference of the test results revealed an only poor inter-test agreement between the test systems. CONCLUSIONS: Results of test kits for the identification of periodontopathogens are significantly influenced by the detection technology applied. The most advanced technology tended to give the most reliable results. CLINICAL RELEVANCE: As microbiological test results are supposed to be used for the planning of subsequent treatment strategies, clinicians should be aware of the limitations of results obtained by the different test systems and should use the results only in conjunction with clinical data for subsequent therapeutic decisions.

In Vitro Preventive Effect and Mechanism of Action of Weissella cibaria CMU against Streptococcus mutans Biofilm Formation and Periodontal Pathogens.

In this study, we evaluated the in vitro anti-biofilm, antibacterial, and anti-inflammatory activity of Weissella cibaria CMU (CMU), an oral probiotic, against periodontopathogens. Compared to other oral probiotics, CMU showed a superior inhibitory effect on the biofilm formation and growth of Streptococcus mutans on orthodontic wires and artificial teeth (p < 0.05). CMU exerted potent antibacterial effects against S. mutans and Porphyromonas gingivalis according to a line test. In human gingival fibroblasts (HGFs) stimulated by P. gingivalis, Fusobacterium nucleatum, or Prevotella intermedia, CMU suppressed the gene expression of pro-inflammatory cytokines [interleukin (IL)-6, IL-1ß, IL-8, and tumor necrosis factor-α] in a dose-dependent manner (p < 0.05). CMU restored the production of the tissue inhibitor of metalloproteinase-1 following its inhibition by P. gingivalis, and it suppressed the expression of matrix metalloproteinase (MMP)-1 and -3 induced by periodontopathogens (p < 0.05). Moreover, CMU needed direct contact with HGFs to exert their anti-inflammatory function, indicating that they act directly on gingival cells to modulate local inflammation. Our preclinical study provides evidence for the potential benefits of topical CMU treatments in preventing the development of caries and periodontitis caused by the dysbiosis of the dental plaque microbiome.

Probiotic Species in the Management of Periodontal Diseases: An Overview.

Periodontal diseases are one of the most common chronic inflammatory diseases of the oral cavity, which are initiated and sustained by pathogenic plaque biofilms. Central to modern periodontology is the idea that dysbiosis of periodontal microecology and disorder of host inflammatory response gives rise to degradation of periodontal tissues together, which eventually leads to tooth loss, seriously affecting the life quality of patients. Probiotics were originally used to treat intestinal diseases, while in recent years, extensive studies have been exploring the utilization of probiotics in oral disease treatment and oral healthcare. Probiotic bacteria derived from the genera Lactobacillus, Bifidobacterium, Streptococcus, and Weissella are found to play an effective role in the prevention and treatment of periodontal diseases via regulating periodontal microbiota or host immune responses. Here, we review the research status of periodontal health-promoting probiotic species and their regulatory effects. The current issues on the effectiveness and safety of probiotics in the management of periodontal diseases are also discussed at last. Taken together, the use of probiotics is a promising approach to prevent and treat periodontal diseases. Nevertheless, their practical use for periodontal health needs further research and exploration.

Lipopolysaccharides of Fusobacterium nucleatum and Porphyromonas gingivalis increase RANKL-expressing neutrophils in air pouches of mice.

Increases of neutrophils and osteoclasts are pathological changes of periodontitis. RANKL is an osteoclast differentiation factor. The effect of periodontopathogen LPS on RANKL-expressing neutrophils has not been clarified yet. We evaluated numerical changes of RANKL-expressing neutrophils in air pouches of mice injected with LPSs of Fusobacterium nucleatum and Porphyromonas gingivalis. Mice with air pouches were assigned into saline (C)-, E. coli LPS- (Ec LPS)-, F. nucleatum LPS (Fn LPS)-, P. gingivalis LPS (Pg LPS)-, and Fn LPS and Pg LPS (Fn + Pg LPS)-injected groups. CD11b+Ly6G+ neutrophils and CD11b+Ly6G+RANKL+ neutrophils in blood and air pouch exudates were determined by flow cytometry. In blood, compared to the C group, the Fn LPS group showed increases of CD11b+Ly6G+ neutrophils and CD11b+Ly6G+RANKL+ neutrophils whereas the Pg LPS group showed no significant differences. These increases in the Fn LPS group were not different to those in the Ec LPS group. In exudates, Fn LPS and Pg LPS groups showed increases of CD11b+Ly6G+ neutrophils and CD11b+Ly6G+RANKL+ neutrophils compared to the C group. Increased levels in the Fn LPS group were not different to those in the Ec LPS group, but Pg LPS group was lower than those in the Ec LPS group. In blood and exudates, the Fn + Pg LPS group showed no difference in levels of these neutrophils compared to the Ec LPS group. LPSs of F. nucleatum and P. gingivalis increased RANKL-expressing neutrophils although the degrees of increases were different. These suggest that periodontopathogen LPS can act as a stimulant to increase RANKL-expressing neutrophils.

The Impact of Smoking on Subgingival Plaque and the Development of Periodontitis: A Literature Review.

Smoking seriously affects oral health and causes a variety of oral diseases. Numerous clinical data show that smoking significantly increases the risk of periodontitis, and the duration and amount of smoking are positively correlated with the severity of periodontitis. In fact, smoking creates an environment conducive to the colonization of periodontopathogens, which affects the process of periodontitis. Since subgingival plaque which harbors periodontopathogens is the initiation factor of periodontitis, it is critical to study the impact of smoking on subgingival microbiota for understanding the relationship between smoking and periodontitis. Continuous advances have been made on the understanding of effects of smoking on subgingival plaque and the development of periodontitis. Smoking is observed to enhance the pathogenicity of periodontopathogens, especially the red complex microorganisms, via promoting their colonization and infection, and regulating the expression and function of multiple virulence factors. Furthermore, smoking has a negative impact on periodontal microecological homeostasis, which is reflected in the decrease of commensal bacteria and the increase of periodontopathogens, as well as the changes in the interaction between periodontopathogens and their commensal microbes in subgingival biofilm, thus influencing the pathogenicity of the subgingival plaque. In summary, the mechanism of smoking on subgingival plaque microorganisms represented by the red complex and its effect on the periodontal microecology still need to be further explored. The relevant research results are of great significance for guiding the periodontal clinical treatment of smoking population. This review summarizes the effects and relevant mechanisms of smoking on subgingival plaque and the development of periodontitis.

Citrullination in periodontium is associated with Porphyromonas gingivalis.

OBJECTIVE: To analyse the citrulline level in the periodontium in association with the presence of or antibody levels against Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. DESIGN: Gingival crevicular fluid (GCF), subgingival biofilm and blood serum were sampled from 98 subjects (26 with RA, 72 without RA (NoRA)). GCF was analyzed for the level of citrulline, for interleukin (IL)-1ß, IL-17, IL-10 and monocyte-chemoattractant protein (MCP)-1. Microorganisms were identified in subgingival biofilms. Antibodies againstP. gingivalis, and Aggregatibacter actinomycetemcomitans were quantified in serum. RESULTS: GCF citrulline level was the lowest (by trend) in NoRA group without periodontitis. In NoRA, but not in RA an association between GCF citrulline level and P. gingivalis antibody levels was found and the GCF citrulline levels were higher in P. gingivalis positive samples. Any association of A. actinomycetemcomitans with GCF citrulline level did not exist. A model of univariate variance analysis (p = 0.001) showed a dependence of GCF citrulline level from the number of sites with PD (probing depth) ≥5 mm (p = 0.003) and the GCF MCP-1/CCL2 level (p = 0.019). Compared with NoRA in RA the number of teeth was lower, the number of sites with PD ≥ 5 mm was less, GCF levels of interleukin-17 and MCP-1/CCL2 were higher and those of IL-10 lower. Yeasts were only cultured in 15 RA patients (p < 0.001). CONCLUSION: Citrullination in periodontium might be associated with P. gingivalis supporting the potential role as a trigger in the development of RA. Pathogenesis of periodontal disease in RA patients seems to differ from that in NoRA and should be investigated further.

Multidisciplinary Clinical Management of a Localized Aggressive Periodontitis diagnosed in a Child with Glanzmann's Thrombasthenia.

Localized aggressive periodontitis (LAP) in child involving primary dentition is a rare disease. The main characteristics of LAP are deep periodontal pockets, bone loss, tooth mobility, and, sometimes, spontaneous tooth loss. The LAP involves only some specific teeth. Glanzmann's thrombasthenia (GT) is a rare autosomal recessive bleeding disorder. The paper's aim is to present the case of a 5-year-old girl with GT presenting LAP, and discuss her clinical management. How to cite this article: Prud'homme T, Roy E, Soueidan A, Fouassier M, Dajean-Trutaud S, Badran Z. Multidisciplinary Clinical Management of a Localized Aggressive Periodontitis diagnosed in a Child with Glanzmann's Thrombasthenia. Int J Clin Pediatr Dent 2018;11(4):344-348.

Development and in vitro evaluation of biopolymers as a delivery system against periodontopathogen microorganisms

Periodontal disease is the major cause of tooth loss in adults. Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans are considered key pathogens in periodontitis. The treatment consists of oral hygiene education, instrumentation for removal of calculus (scaling), chemotherapy and periodontal surgery. Several agents are commercially available; these chemicals can alter oral microbiota and have undesirable sideeffects such as vomiting, diarrhea and tooth staining. Hence, the search for alternative products continues and natural phytochemicals isolated from plants used as traditional medicine and the use of biomaterials are considered good alternatives. Chitosan and pullulan are polymers that have been proposed due to their favorable properties such as biocompatibility, biodegradability, and adhesion ability. They can be used as local delivery systems of active principles of plant extracts. Thymus vulgaris, Matricaria chamomilla, Croton lechleri, Calendula officinalis L. and Juliana adstringens Schl. are known to have medicinal activity, and they are used in Mexican traditional medicine. Their extracts were tested in vitro for antimicrobial activity against P. gingivalis and A. actinomycetemcomitans, using agar diffusion and microdilution methods. The antimicrobial activity of films from biopolymers with plant extracts was evaluated by measuring the zones of inhibition against the tested organisms. The aim of this study was to develop bioadhesive films from chitosan and pullulan with added plant extracts and determine the antimicrobial activity of films against periodontal pathogens.

La enfermedad periodontal es la principal causa de perdida de dientes en los adultos. Los agentes causales comunmente identificados con la enfermedad son Porphyromonas gingivalis y Aggregatibacter actinomycetemcomitans. El tratamiento de la enfermedad consiste en educacion sobre higiene oral, remocion de calculos por medio de instrumentacion (raspado y alisado de la raiz), la administracion de medicamentos y cirugia. Hay multiples agentes quimicos disponibles comercialmente; estos pueden alterar la microflora oral y tener efectos secundarios indeseables como vomito, diarrea y pigmentacion dental. Por lo tanto, los productos naturales como los fitoquimicos aislados de plantas que son usadas como medicinas tradicionales y los biomateriales, son considerados buenas alternativas. El quitosan y el pululan son polimeros que han sido propuestos debido a sus propiedades de biocompatibilidad, biodegradabilidad, habilidad de adhesion y que pueden ser usados como sistemas de liberacion de los principios activos de extractos de plantas. Los extractos de Thymus vulgaris, Matricaria chamomilla, Croton lechleri, Calendula officinalis L. y Juliana adstringens Schl. son conocidos por tener actividad medicinal y se usan en la medicina tradicional Mexicana. La actividad antimicrobiana de sus extractos fue probada in vitro contra P. gingivalis y A. actinomycetemcomitans usando los metodos de difusion en agar y de microdilucion. La actividad antimicrobiana de peliculas a base de biopolimeros con extractos de plantas fue evaluada midiendo las zonas de inhibicion de crecimiento de los organismos probados. El proposito de este estudio fue desarrollar peliculas bioadhesivas de quitosan y pululan adicionadas con extractos de plantas y evaluar su actividad antimicrobiana contra periodontopatogenos.