Effect of ovarian dysfunction induced ovariectomy and Porphyromonas gingivalis induction to risk of metabolic syndrome: in vivo study / Efeito da disfunção ovariana por meio de ovariectomia e indução de Porphyromonas gingivalis no risco de desenvolvimento de síndrome metabólica: estudo in vivo

Doenças periodontais e síndrome metabólica estão relacionadas a condições multifatoriais complicadas. No entanto, a relação ainda não é evidente. A insuficiência de estrogênio pode estar correlacionada a essa condição, possivelmente causada pela remoção dos ovários e infecção por Porphyromonas gingivalis (P. gingivalis). Este estudo teve como objetivo avaliar o efeito da disfunção ovariana causada pela ovariectomia e infecção por P. gingivalis no desenvolvimento da síndrome metabólica. Este foi um estudo experimental de laboratório utilizando ratos fêmeas da linhagem Sprague Dawley. Os modelos animais foram divididos em quatro grupos: controle, ovariectomia (OVX), ovariectomia-periodontite (OPG) e periodontite (PG). O objetivo de cada tratamento em cada grupo foi obter disfunção ovariana. O grupo OVX foi submetido à cirurgia de remoção dos ovários; no grupo PG foi realizada a indução de P. gingivalis; e no grupo OPG foi feita uma combinação de ovariectomia e indução de P. gingivalis. O sangue foi coletado e observado nos dias 0, 3, 7, 14, 21 e 28. A amostra de sangue foi examinada para ácido úrico, colesterol, glicose e estrogênio. Os dados coletados foram todos examinados estatisticamente. Todos os grupos de tratamento apresentaram peso corporal e observações bioquímicas sanguíneas significativamente maiores do que o grupo controle, exceto o colesterol total (p<0,05). Além disso, a maioria das variáveis apresentou uma correlação entre os grupos com o peso corporal e indicadores bioquímicos sanguíneos, exceto o nível de ácido úrico no sangue (R>0,5). A síndrome metabólica foi desencadeada pela disfunção ovariana causada pela infecção por P. gingivalis após a ovariectomia. Ambos apresentaram o mesmo risco. Mesmo a indução por P. gingivalis piorou a síndrome metabólica no grupo de modelos animais que foram submetidos à ovariectomia.(AU)

Periodontal diseases and metabolic syndrome are related to complicated multifactorial conditions. However, the relationship is not yet evident. Estrogen insufficiency might correlate to this condition, possibly caused by ovarian removal and Porphyromonas gingivalis (P. gingivalis) infection. This study aimed to evaluate the effect of ovarian dysfunction caused by ovariectomy and P. gingivalis infection to metabolic syndrome development. This study was an experimental laboratory study using female rats Sprague Dawley Strain. Animal models were divided into four groups: control, ovariectomy (OVX), ovariectomy-periodontitis (OPG), and periodontitis (PG). The purpose of every treatment in each group was to induce ovarian dysfunction. The OVX group was undertaken ovaries removal surgery. PG was performed P. gingivalis induction. Therefore OPG was a combination of ovariectomy and P. gingivalis induction. Blood was drawn and observed on days 0, 3, 7, 14, 21, and 28. The blood sample was examined for uric acid, cholesterol, glucose and estrogen. The collected data were all statistically examined. All treatment groups presented body weight and blood biochemical observation significantly higher than the control group, except total cholesterol (p<0.05). Moreover, most variables presented a correlation between groups to body weight and biochemical blood indicators, except blood uric acid level (R>0.5). The metabolic syndrome was triggered by ovarian dysfunction brought on by P. gingivalis infection after ovariectomy. They both took the same risk. Even P. gingivalis induction made metabolic syndrome in the group of animal models which underwent ovariectomy worse (AU)

Superoxide Dismutase Expression in the Ovaries of Periodontitis Animal Models Induced by Porphyromonas gingivalis and Treated with Cassava Leaves Extract

@#The ovaries represent the female reproductive organs that determine the women's fertility status and their systemic and oral health, correlating to sex steroid hormone alteration. This study aimed to investigate the effect of cassava leaves extract treatment to SOD expression in the animal model-ovaries after Porphyromonas gingivalis injection. 15 female Sprague Dawley rats were used and divided into five groups: (1) control without cassava leaves extract treatment (C); (2) P. gingivalis without cassava leaves extract treatment (T1); (3) P. gingivalis and cassava leaves extract (T2); (4) P. gingivalis and vitamin C (T3); and (5) P. gingivalis and metronidazole (T4). Animal were euthanised at day seven after the initial treatment to collect ovaries. The ovaries sections were immunohistochemically stained to quantify SOD expression using light microscope while the Image J software was used to quantify the SOD expression. The results showed that all of the follicle types had the same intensity of SOD expression. Most of the follicles exhibited low intensity of SOD expression, except for atretic follicles. In conclusion, P. gingivalis and cassava leaves extract influenced SOD expression in the ovaries of animal models, which increased the SOD expression.

Xylitol Mitigate Neutrophil Inflammatory Response Against Porphyromonas gingivalis Infection

Periodontitis is generally a chronic disorder characterized by breakdown of tooth-supporting tissues, producing dentition loss. Porphyromonas gingivalis (P. gingivalis), a Gram-negative anaerobic rod, is one of the major pathogens associated with periodontitis. Neutrophils are first line defense cells in the oral cavity that play a significant role in inflammatory response. Xylitol is a known anti-caries agent and has anti-inflammatory effects. In this study, we conducted experiments to evaluate anti-inflammatory effects of xylitol on P. gingivalis infected neutrophils for possible usage in prevention and treatment of periodontal infections. P. gingivalis was intraperitoneally injected and peritoneal lavage was collected for cytokine determination. For in vitro study, neutrophils were collected from mouse peritoneal cells after zymosan injection or bone marrow cells. Neutrophils were stimulated with live P. gingivalis and ELISA was used to determine the effect of xylitol on P. gingivalis induced cytokine production. IL-1β, IL-6, TNF-α concentration and neutrophil population in the peritoneal lavage was increased in P. gingivalis-infected mouse. Peritoneal cells infected with live P. gingivalis revealed significantly increased production of IL-1β, IL-6 and TNF-α at multiplicity of infection of 10. Neutrophils from bone marrow and peritoneal lavage revealed increased production of IL-1β, IL-6 and TNF-α. Xylitol significantly mitigated P. gingivalis induced cytokine production in neutrophils. Findings indicate that xylitol is an anti-inflammatory agent in neutrophils infected with live P. gingivalis, that suggests its use in periodontitis management.

Effect of Various Agents on Oral Bacterial Phagocytosis in THP-1 Cells

Phagocytosis is a fundamental process in which phagocytes capture and ingest foreign particles including pathogenic bacteria. Several oral pathogens have anti-phagocytic strategies, which allow them to escape from and survive in phagocytes. Impaired bacteria phagocytosis increases inflammation and contributes to inflammatory diseases. The purpose of this study is to investigate the influences of various agents on oral pathogenic phagocytosis. To determine phagocytosis, Streptococcus mutans, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were stained with 5-(and-6)-carboxyfluorescein diacetate succinimidyl ester (CFSE), and was measured using flowcytometery and confocal microscopy. The influencing factors on phagocytosis were evaluated through the pretreatment of ROS inhibitor (N-acetyl-L-cysteine (NAC)), lysozyme, potassium chloride (KCI) and adenosine triphosphate (ATP) in THP-1 cells. Expression of pro-inflammatory cytokines was determined by enzyme-linked immunosorbent assay (ELISA). The phagocytosis of various bacteria increased in a MOI-dependent manner. Among the tested bacteria, phagocytosis of P. gingivalis showed the highest fluorescent intensity at same infection time. Among the tested inhibitors, the NAC treatment significantly inhibited phagocytosis in all tested bacteria. In addition, NAC treatment indicated a similar pattern under the confocal microscopy. Moreover, NAC treatment significantly increased the bacteria-induced secretion of IL-1β among the tested inhibitors. Taken together, we conclude that the phagocytosis occurs differently depending on each bacterium. Down-regulation by ROS production inhibited phagocytosis and lead increased of oral pathogens-associated inflammation.

Associação entre artrite reumatoide e citrulinização proteica por porphyromonas gingivalis: revisão de literatura / Association between Rheumatoid Arthritis and protein citrulinization by Porphyromonas gingivalis: Literature Review

A presença de peptidil-arginina deaminase (PADs), enzimas de Porphyromonas gingivalis (P. gingivalis), encontradas em pacientes com periodontite, são capazes de quebrar a tolerância imune, mediante citrulinização proteica, culminando, em um paciente suscetível, ao desenvolvimento da artrite reumatoide (AR). O objetivo desta revisão de literatura é avaliar uma possível correlação entre a periodontite e AR por meio da citrulinização proteica realizada por P. gingivalis. Para o desenvolvimento desta revisão de literatura, foi realizada uma busca na base de dados eletrônicas PUBMED, no período de maio a agosto de 2017. Foi utilizada uma estratégia de busca otimizada com as seguintes palavraschave: rheumatoid arthritis, periodontal disease e P. gingivalis. Assim, foram encontrados um total de 83 artigos, sendo selecionados inicialmente por título e resumo por um revisor e, posteriormente, por outro revisor, selecionando pelos critérios de inclusão: artigos completos escritos em língua portuguesa, espanhola ou inglesa; ter 10 anos ou menos de publicação. Ao final da seleção foram obtidos 22 artigos; destes, 15 incluídos por serem estudos clínicos em animais ou humanos. De acordo com este estudo, foi possível correlacionar positivamente a periodontite e a AR por meio da citrulinização proteica realizada pela bactéria P. gingivalis. Contudo, a mediação por PADs não é a única e exclusiva forma de correlação entre essas doenças, sendo necessários mais estudos para estabelecer outras possíveis correlações. (AU)

The presence of peptidyl arginine deaminase (PADs), an enzyme associated to Porphyromonas gingivalis (P. gingivalis), found in patients with periodontitis, can lead to the breakdown of immune tolerance by means of protein citrulinization, leading to a development of rheumatoid arthritis (RA) in susceptible patients. The objective of this literature review is to evaluate a possible correlation between periodontitis and RA through protein citrulinization performed by P. gingivalis. For the development of this literature review, a search was performed on the electronic database PUBMED from May to August 2017. An optimized search strategy was used with the following keywords: rheumatoid arthritis, periodontal disease and P. gingivalis. A total of 83 articles were found, being initially selected by title and abstract by one reviewer and later by another reviewer selecting by inclusion criteria: Complete articles written in Portuguese, Spanish or English; have 10 years or less of publication. At the end of the selection, 22 articles were obtained; of these, 15 included by being clinical studies in animals or humans. According to this study, it is possible to positively correlate periodontitis and RA with protein citrulinization performed by P. gingivalis. However, mediation by PADs is not the only and exclusive form of correlation between these diseases, and further studies are needed to establish other possible correlations. (AU)

Chracterization of THP-1 Cell Death Induced by Porphyromonas gingivalis Infection

BACKGROUND: Periodontitis is generally a chronic disorder characterized by the breakdown of tooth-supporting tissues. P. gingivalis, a Gram-negative anaerobic rod, is one of the major pathogens associated with periodontitis. Frequently, P. gingivalis infection leads to cell death. However, the correlation between P. gingivalis–induced cell death and periodontal inflammation remains to be elucidated. Among cell deaths, the death of immune cells appears to play a significant role in inflammatory response. Thus, the aim of this study was to examine P. gingivalis–induced cell death, focusing on autophagy and apoptosis in THP-1 cells. METHODS: Human acute monocytic leukemia cell line (THP-1) was used for all experiments. Autophagy induced by P. gingivalis in THP-1 cells was examined by Cyto ID staining. Intracellular autophagic vacuoles were observed by fluorescence microscopy using staining Acridine orange (AO); and 3-methyladenine (3-MA) was used to inhibit autophagy. Total cell death was measured by LDH assay. Cytokine production was measured by an ELISA method. RESULTS: P. gingivalis induced autophagy in an MOI-dependent manner in THP-1 cells, but 3-MA treatment decreased autophagy and increased the apoptotic blebs. P. gingivalis infection did not increase apoptosis compared to the control cells, whereas inhibition of autophagy by 3-MA significantly increased apoptosis in P. gingivalis-infected THP-1 cells. Inhibition of autophagy by 3-MA also increased total cell deaths and inflammatory cytokine production, including IL-1β and TNF-α. CONCLUSION: P. gingivalis induced autophagy in THP-1 cells, but the inhibition of autophagy by 3-MA stimulated apoptosis, leading to increased cell deaths and pro-inflammatory cytokines production. Hence, the modulation of cell deaths may provide a mechanism to fight against invading microorganisms in host cells and could be a promising way to control inflammation.

Posible papel de Porphyromonas gingivalis en el desarrollo de la artritis reumatoide / Possible role of Porphyromonas gingivalis in the develpment of rheumatoid arthritis

Varios estudios han sugerido una asociación entre la periodontitissevera, la prevalencia de la bacteria Porphyromonas gingivalis y el desarrollo de artritis reumatoide. Como fundamento de esta relación, se ha observado que esta bacteria secreta una enzima, peptidil-arginina deiminasa, que es capaz de citrulinar proteínas del hospedero y así favorecer una respuesta autoinmune. Sin embargo, debido a la heterogeneidad de diseños experimentales, selección de pacientes y valoración de los desenlaces, los resultados no han mostrado la reproducibilidad deseada. Asimismo, observaciones recientes apuntan a que la actividad enzimática podría ser generada por otras especies bacterianas, lo que hace más compleja su relación. Sin embargo, por otro lado, algunos estudios sugieren que el tratamiento periodontal puede limitar el desarrollo de la artritis reumatoide.

Various studies have suggested a link between severe periodontitis,the prevalence of Porphyromonas gingivalis, and the development ofrheumatoid arthritis. As evidence of this relationship, P. gingivalis hasbeen found to secrete an enzyme, peptidyl arginine deiminase, which isable to citrullinate host proteins and thus help activate an autoimmuneresponse. However, due to the heterogeneity of experimental designs,patient selection, and assessment of clinical outcomes, the results havenot shown the desired reproducibility. Furthermore, recent fi ndingsindicate that the enzymatic activity may be produced by other species ofbacteria, which suggests the relationship is more complex. However, anumber of studies have shown that periodontal treatment could inhibitthe development of rheumatoid arthritis.

Contribution of Periodontal Disease in Atherosclerosis

Periodontitis is a disease that leads to destruction of the soft and hard tissues of periodontium, which can result in periodontal bone loss and tooth loss in severe cases. Atherosclerosis is a disease characterized by artery wall thickening as a result of invasion and accumulation of foam cells. Epidemiologic studies have suggested the association with periodontitis and atherosclerosis. Periodontopathogens are frequently found in atheroma plaque. The possible mechanisms for systemic dissemination of oral bacteria have been suggested: 1) direct translocation of bacteria from dental plaque to systemic circulation through transcellular mechanism or by physical perturbations of the gingiva, 2) indirect dissemination to distant sites via survival in immune cells including macrophages and dendritic cells. There are several mechanisms by which oral bacteria may contribute to atherosclerosis development: 1) activation of innate immune response, 2) mediators activated by oral bacteria and 3) involvement of cytokines and heat shock proteins from oral bacteria. Thus, better understanding the role of periodontitis in atherosclerosis may be the key to improve the prevention and treatment of atherosclerosis.

Bacteriological analysis of necrotic pulp and fistulae in primary teeth

Objectives: Primary teeth work as guides for the eruption of permanent dentition, contribute for the development of the jaws, chewing process, preparing food for digestion, and nutrient assimilation. Treatment of pulp necrosis in primary teeth is complex due to anatomical and physiological characteristics and high number of bacterial species present in endodontic infections. The bacterial presence alone or in association in necrotic pulp and fistula samples from primary teeth of boys and girls was evaluated. Material and Methods: Necrotic pulp (103) and fistula (7) samples from deciduous teeth with deep caries of 110 children were evaluated. Bacterial morphotypes and species from all clinical samples were determined. Results: A predominance of gram-positive cocci (81.8%) and gram-negative coccobacilli (49.1%) was observed. In 88 out of 103 pulp samples, a high prevalence of Enterococcus spp. (50%), Porphyromonas gingivalis (49%), Fusobacterium nucleatum (25%) and Prevotella nigrescens (11.4%) was observed. Porphyromonas gingivalis was detected in three out of seven fistula samples, Enterococcus spp. in two out of seven samples, and F. nucleatum, P. nigrescens and D. pneumosintes in one out of seven samples. Conclusions: Our results show that Enterococcus spp. and P. gingivalis were prevalent in necrotic pulp from deciduous teeth in boys from 2 to 5 years old, and that care of the oral cavity of children up to five years of age is important. .

Detection of putative periodontopathic bacteria in type 1 diabetic and healthy children: A comparative study.

Aim: The aim of this study was to compare and assess the risk of periodontitis due to the presence of four putative periodontopathic bacteria (Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Aggregatibacter actinomycetemcomitans) in type 1 diabetic and healthy children. Materials and Methods: Fifty type 1 diabetic and 50 healthy children in the age group of 7-14 years were recruited for the study. Subgingival plaque samples collected from permanent first molars were subjected to polymerase chain reaction assay to detect 16S rRNA gene of P. gingivalis, T. forsythia, T. denticola and A. actinomycetemcomitans. The data were analyzed using Fisher exact test. The P < 0.05 was considered statistically significant. Results: The prevalence of subgingival periodontal pathogens in diabetic and healthy children was 2% and 4% for P. gingivalis, 34% and 34% for T. denticola, 20% and 18% for A. actinomycetemcomitans and for T. forsythia, 4% and 34%, respectively. Significant statistical difference was not observed with regard to the prevalence of P. gingivalis, T. denticola, and A. actinomycetemcomitans among type 1 diabetic and healthy children (P = 1.00). Conversely, T. forsythia was less prevalent in diabetic children compared to healthy children. Conclusion: Statistical significance was not observed for the prevalence of periodontopathic bacteria in type 1 diabetic subjects. The results of the present study thus reveal the absence of risk of periodontitis by these bacterial species in type 1 diabetic subjects.

Porphyromonas gingivalis resistance to polymyxin B is determined by the lipid A 4'-phosphatase, PGN_0524 / 国际口腔科学杂志·英文版

<p><b>AIM</b>To elucidate the genetic basis for the pronounced resistance that the oral pathogen, Porphyromonas gingivalis (P. gingivalis), exhibits towards the cationic antimicrobial peptide, polymyxin B.</p><p><b>METHODOLOGY</b>A genetic screen of P. gingivalis clones generated by a Tn4400'-based random insertion mutagenesis strategy was performed to identify bacteria harboring novel genetic mutations that render P. gingivalis susceptible to killing by the cationic antimicrobial peptide, polymyxin B (PMB, 50 microg x mL(-1)).</p><p><b>RESULTS</b>P. gingivalis (ATCC 33277) is unusually resistant to the cationic antimicrobial peptide, PMB at relatively high concentrations (200 microg x mL(-1)). Approximately 2,700 independent Tn4400'-derived mutants of P. gingivalis were examined for increased sensitivity to PMB killing at a relatively low dose (50 microg x mL(-1)). A single PMB-sensitive mutant was obtained in this phenotypic screen. We determined that the Tn4400' transposon was integrated into the gene encoding the lipid A 4'-phosphatase, PGN_0524, demonstrating that this insertion event was responsible for its increased susceptibility of this clone to PMB-dependent killing. The resulting mutant strain, designated 0524-Tn4400', was highly sensitive to PMB killing relative to wild-type P. gingivalis, and exhibited the same sensitivity as the previously characterized strain, 0524KO, which bears a genetically engineered deletion in the PGN_0524 locus. Positive ion mass spectrometric structural (MALDI-TOF MS) analyses revealed that lipid A isolates from 0524-Tn4400' and 0524KO strains displayed strikingly similar MALDI-TOF MS spectra that were substantially different from the wildtype P. gingivalis lipid A spectrum. Finally, intact 0524-Tn4400' and 0524KO mutant bacteria, as well as their corresponding LPS isolates, were significantly more potent in stimulating Toll-like receptor 4 (TLR4)-dependent E-selectin expression in human endothelial cells relative to intact wild-type P. gingivalis or its corresponding LPS isolate.</p><p><b>CONCLUSION</b>The combined molecular evidence provided in this report suggests that PGN_0524, a lipid A 4'-phosphatase, is the sole genetic element conferring the ability of the periodontopathogen, P. gingivalis, to evade the killing activity of cationic antimicrobial peptides, such as PMB. These data strongly implicate PGN_0524 as a critical virulence factor for the ability of P. gingivalis to evade front-line host innate defenses that are dependent upon cationic antimicrobial peptide activity and TLR 4 sensing.</p>

Production and characterization of cross-reactive anti-Porphyromonas gingivalis heat shock protein 60 monoclonal antibody / 대한치주과학회지

PURPOSE: Porphyromonas gingivalis (P. gingivalis) heat shock protein (HSP)60 may play a role in the immunopathogenesis of periodontitis as well as atherosclerosis by modulating autoimmune reaction due to its high level of sequence homology between bacteria and human counterpart. The purpose of this study was to identify immunodomiant epitope of P. gingivalis HSP60 that is reactive exclusively to the homologous bacteria without reacting with human HSP. MATERIALS AND METHODS: The present study was performed to identify the peptide specifically recognized by anti-P. gingivalis HSP60 monoclonal antibodies mono-reactive to P. gingivalis HSP60. RESULTS: Four different hybridomas were cloned producing monoclonal IgG antibodies exclusively to P. gingivalis HSP60. Thirty seven synthetic peptides (20-mer with 5-amino acid overlapping) were synthesized. All of these peptide were subject to SDS-PAGE for immunblot analysis. One peptide (TVPGGGTTYIRAIAALEGLK) and the other peptide (TLVVNRLRGSLKICAVKAPG) were recognized by all and one of the four monoclonal antibodies, respectively, that reacted solely with P. gingivalis HSP60. Immunohistochemistry to identify the localization of the HSP60 in the diseased gingival tissues revealed that all of the four monoclonal antibodies were highly reacted with the diseased gingival tissue than normal gingival tissue. CONCLUSION: The P. gingivalis HSP60 peptides (TVPGGGTTYIRAIAALEGLK and TLVVNRLRGSLKICAVKAPG, respectively) are positively involved in the immunopathologic process of periodontal disease. The peptide may potentially be developed as vaccine candidates. Further investigations are under way to identify more clones producing monoclonal antibodies reactive to P. gingivalis HSP and to other periodontopathogenic bacteria as well, while maintaining specificities to human counterpart.

The influence of adjacent tooth to the microbiology of implant sulcus / 대한치주과학회지

The aim of present study is to evaluate the influence of adjacent tooth to the microbiology of clinically healthy implant. Control group included patients who had clinically healthy implant and tooth with healthy periodontium(PD 3mm). The criteria of clinically health implant are no pain or discomfort, the restorative suprastructure provide satisfactory fit and function, and the tissue around the fixtures were firm and probing with standard periodontal probe with a rounded tip 0.5mm in diameter resulted in penetration of no more than 5mm when using a force of 0.5N at any location. 38 patients, partially edentulous subjects with endosseous root-form implants were selected. All subjects were medically healthy and had not taken systemic antibiotics and professional plaque control 3 months before sampling. Number of control group is 25(mean age 52+/-13, 26 teeth, 34 implants) and test group is 13(mean age 60+/-13, 13 teeth, 17 implants). All teeth and implants of each patient were examined probing depth(PD), bleeding on probing(BOP), and plaque index(PI), and samples of subgingival plaque were obtained at each site with sterile curet or fine paper points, then the plaque transferred to PBS. Obtained samples were examined for the presence of P. gingivalis, T. forsythensis, and T. denticola by the polymerase chain reaction(PCR). The relationship among clinical parameters and the colonizations by the 3 bacterial species from natural teeth and implants region were analyzed by student t-test. The results of this study were as follows: 1. PD was different in teeth between 2 groups(p<0.05), but the other parameters were not. 2. Statistically significant difference was not found in clinical parameters of implants between 2 groups. 3. All bacterial prevalences of teeth were higher in test group than in control group, and prevalence of T. forsythensis had statistically significant difference between 2 groups(p<0.05). 4. Prevalences of P. gingivalis and T. forsythensis are higher in test group than control group, and that of T. denticola is higher in control group than in test group. But there were no statistically significant differences between 2 groups. In conclusion, there is no statistically significant difference in prevalence of implant microbiology between 2 groups. But if the number of samples increased, it will be possible to find out statistical significance in prevalence of P. gingivalis. It seems that pocket of adjacent tooth influences prevalence of P. gingivalis. These results mean that improvement of the periodontal condition before implantation is very important.

The influence of adjacent tooth to the microbiology of implant sulcus / 대한치주과학회지

The aim of present study is to evaluate the influence of adjacent tooth to the microbiology of clinically healthy implant. Control group included patients who had clinically healthy implant and tooth with healthy periodontium(PD 3mm). The criteria of clinically health implant are no pain or discomfort, the restorative suprastructure provide satisfactory fit and function, and the tissue around the fixtures were firm and probing with standard periodontal probe with a rounded tip 0.5mm in diameter resulted in penetration of no more than 5mm when using a force of 0.5N at any location. 38 patients, partially edentulous subjects with endosseous root-form implants were selected. All subjects were medically healthy and had not taken systemic antibiotics and professional plaque control 3 months before sampling. Number of control group is 25(mean age 52+/-13, 26 teeth, 34 implants) and test group is 13(mean age 60+/-13, 13 teeth, 17 implants). All teeth and implants of each patient were examined probing depth(PD), bleeding on probing(BOP), and plaque index(PI), and samples of subgingival plaque were obtained at each site with sterile curet or fine paper points, then the plaque transferred to PBS. Obtained samples were examined for the presence of P. gingivalis, T. forsythensis, and T. denticola by the polymerase chain reaction(PCR). The relationship among clinical parameters and the colonizations by the 3 bacterial species from natural teeth and implants region were analyzed by student t-test. The results of this study were as follows: 1. PD was different in teeth between 2 groups(p<0.05), but the other parameters were not. 2. Statistically significant difference was not found in clinical parameters of implants between 2 groups. 3. All bacterial prevalences of teeth were higher in test group than in control group, and prevalence of T. forsythensis had statistically significant difference between 2 groups(p<0.05). 4. Prevalences of P. gingivalis and T. forsythensis are higher in test group than control group, and that of T. denticola is higher in control group than in test group. But there were no statistically significant differences between 2 groups. In conclusion, there is no statistically significant difference in prevalence of implant microbiology between 2 groups. But if the number of samples increased, it will be possible to find out statistical significance in prevalence of P. gingivalis. It seems that pocket of adjacent tooth influences prevalence of P. gingivalis. These results mean that improvement of the periodontal condition before implantation is very important.

Relation between the interval of supportive periodontal therapy and the prevalence of the subgingival microflora / 대한치주과학회지

This study was performed to evaluate the relation between the interval of supportive periodontal therapy and the prevalence of the subgingival microflora. The subgingival plaques from 108 patients were used in the study. Control group were the patients with no periodontal treatment and test groups were assigned into 3 groups according to the period of recall check : group 1; 1-2 months, group 2; 3-4 months, group 3; 6months or more. The polymerase chain reaction (PCR) used for direct identification of periodontal pathogens (P. gingivalis, T. forsythensis, T. denticola) in subgingival plaque. The results of this study were as follows. 1. The prevalence of P. gingivalis, T. forsythensis, T. denticola in control group were 100%, 87%, 90%. 2. In clinical parameters such as plaque index, gingival index, bleeding on probing, control group was not significant different with group 1 but significant different with group 2, group 3. 3. In group 1, the majority of P. gingivalis had type II fimA. 4. When group 3 were compared with group 1, the prevalence of P. gingivalis increased. But the prevalence of P. gingivalis with type II fimA, which have the virulence factor, decreased. 5. We were unable to find the correlation between P. gingivalis with type IV fimA and periodontal disease. 6. The prevalence of T. forsythensis, T. denticola in test group were 85%, 93% or more. From the above results, we were able to find the relation between the interval of supportive periodontal therapy and the prevalence of the subgingival microflora and the need of the strict supportive periodontal therapy to prevent recurrence of periodontal disease, because there were high prevalence of periodontal pathogens.

Prevalence of fimA Genotypes of Porphyromonas gingivalis Strains in peri-implantitis patients / 대한치주과학회지

Fimbriae (fimA) of Porphyromonas gingivalis are filamentous components on the cell surface and are thought to play an important role in the colonization and invasion of periodontal tissue. P. gnigivalis fimA gene encoding fimbrillin, a subunit of fimbriae, has been classified into 5 genotypes (typesI to V) based on the nucleotide sequences. In the present study, we examined the prevalence of these fimA genotypes in patients with dental implant and the relationship between prevalence of these genotypes and peri-implantitis. Dental plaque specimens obtained from 80 peri-implant sulci of 50 patients with dental implants were analyzed by 16S rRNA fimA gene-directed PCR assay. P. gingivalis were detected in 74.4% of the samples of the control group (healthy peri-implant sulci; probing depth or =5mm). Among the P. gingivalis-positive samples of the control group, the most prevalent fimA type was typeI(29.3%), followed by typeII(26.8%). In contrast, a majority among the P. gingivalis-positive samples of the test group was typeII(56.5%), followed by typeI(43.5%). TypeII fimA genotype organisms were detected more frequently in the test group and a significant difference in the occurrence of typeII was observed between test and the control groups. A correlation between specific fimA types and peri-implant health status was found in typeII(OR 3.545) and only a weak relationship was revealed in typeIV(OR 3.807). These findings indicate that P. gingivalis strains that possess typeII fimA are predominant in peri-implant sulci with peri-implantitis and are closely associated with peri-implant health status. P. gingivalis with typeII fimA may be involved in peri-implantitis.

Difference in Prevalence of fimA Genotypes of Porphyromonas gingivalis between Smoker and non-smoker Patients with Periodontitis

Smoking is the most important environmental risk factor for the initiation and progression of periodontitis. However, its effect on periodontopathic Porphyromonas gingiavalis with respect to changes in physicochemical characteristics and prevalence of the pathogen in periodontitis patients remain to be elucidated. The present study was performed to examine the effect of cigarette smoking on the growth, protein profile, and prevalence of P. gingivalis genotypes in smoker and non-smoker periodontitis patients. The growth of P. gingivalis strains 2561 and 9-14K-1 in cigarette puffdissolved culture medium (CM) for 24 and 48 h was inhibited approximately 40% as compared to their growth in non-CM, but the growth of strains A7A1-28 and W50 was inhibited in CM by approximately 15%, revealing that they were relatively resistant to cigarette puff. In contrast, the growth of P. gingivalis HNA-99 was enhanced in CM by 11% after the 24-h incubation. However, its growth after the 48-h incubation decreased by 11% in CM. SDS-polyacrylamide gel electrophoresis and immunoblot analyses demonstrated that the expression of fimbriae in P. gingivalis strains 2561 and 9-14K-1, which were sensitive to cigarette puff, was reduced. On the other hand, the expression of fimbriae was rather increased in the cigarette puff-resistant strains A7A1-28 and W50. Decrease in autoagglutination of P. gingivalis 2561 grown in CM supported the fact that fimbrial expression in the cigarette puff-sensitive strain 2561 had been diminished. Genotypes of P. gingivalis in the subgingival plaque from 22 smoker and 32 non-smoker periodontitis patients was examined by 16S rRNA fimA gene-directed PCR. The prevalence of P. gingivalis was higher in the smokers (95.5%) than in the non-smokers (81.3%). Among the 5 fimA genotypes of P. gingivalis, genotype V, to which the cigarette puff-resistant strain HNA-99 belongs, was most prevalent in the non-smokers (57.4%). Although genotype V was found in 59.1% of the smokers, its prevalence in the smokers was second to that of genotype II. Genotype II, of which A7A1-28 is a representative, was observed to be predominant and seemed to be more closely related to smoking since its occurrence in the smokers was 63.6%, but only 21.9% in the non-smokers. The overall results suggest that cigarette smoking may directly affect physicochemical characteristics of P. gingivalis including the expression of fimbriae, which may play an important role in the resistance of the bacterium to cigarette puff. Therefore, P. gingivalis strains that can express fimbriae under cigarette puff-conditions may be favored to survive the conditions.

Establishment of a Mouse Model of Infection-Induced Atheroma Formation / 대한치주과학회지

No abstract available.

Antibacterial effect of polyphosphate on endodontopathic bacteria / 대한치과보존학회지

This study was performed to observe the antibacterial effect of polyphosphate (polyP) with various chain lengths (P3~P75) on virulent, invasive strains of P. gingivalis A7A1-28 and W50, and multidrug resistant E. faecalis ATCC29212. P. gingivalis strains were grown in brain-heart infusion broth (BHI) containing hemin and vitamin K with or without polyP. PolyP was added at the very beginning of the culture or during the exponential growth phase of the culture. Inhibition of the growth of P. gingivalis was determined by measuring the absorbancy at 540nm of the grown cells. Viable cell counts of the culture and release of intracellular nucleotide from P. gingivalis were measured. E. faecalis was grown in plain BHI with antibiotics alone or in combination with polyP(calgon; 0.1~1.0%) and the bacterial absorbancy was measured. The overall results suggest that polyP has a strong antibacterial effect on the growth of the virulent strains of P. gingivalis and the antibacterial activity of polyP seems largely bactericidal, accompanying bacteriolysis in which chelation phenomenon is not involved. Although polyP does not exert antibacterial activity against E. faecalis, it appears to increase antibacterial effect of erythromycin and tetracycline on the bacterium. Therefore, polyP alone or in combination with antibiotics may be developed as a candidate for the agent controlling oral infections including endodontic infection.

Expression of gingipain K in Porphyromonas gingivalis in the subgingival plaque of puberty gingivitis / 实用口腔医学杂志

Objective:To detect and compare the intensity of gingipain K(Kgp)in culture medium and cell extract of Porphyromonas gingivalis(P.gingivalis)isolates in puberty gingivitis,and then to reveal the possible relationship between Kgp and puberty gingivitis.Methods:36 patients with puberty gingivitis aged from 14 to 17 years were enrolled.Clinical parameters including GI,SBI and PD were evaluated before subgingival plaque samples collection.Subgingival plaque samples were collected and then P.gingivalis isolates were obtained.16S rRNA PCR was used to confirm the presence of P.gingivalis in clinical isolates.Bacteria were cultured in BHI agar base and harvested at the end of log-phase growth.Culture fractions of P.gingivalis(culture medium and cell extracts)were performed with SDS-PAGE and Western blot technique using primary antibody against specific anti-Kgp N-terminal IgG subdomain.The data were statistically analyzed using SPSS 11.5 software.The relationship between the Kgp intensity and the clinical parameters was statistically analyzed using sum rank test.Results:There was positive correlation between the intensity of Kgp N-terminal IgG subdomain and the clinical parameters(P