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Concept: Porphyromonas gingivalis

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Emingil G, Han B, Özdemir G, Tervahartiala T, Vural C, Atilla G, Baylas H, Sorsa T. The effect of azithromycin, as an adjunct to nonsurgical periodontal treatment, on microbiological parameters and gingival crevicular fluid biomarkers in generalized aggressive periodontitis. J Periodont Res 2012; 47: 729-739. © 2012 John Wiley & Sons A/S Background and Objective:  To study the effectiveness of azithromycin in combination with nonsurgical periodontal therapy on clinical and microbiological parameters, and on the MMP-8 and TIMP-1 levels in gingival crevicular fluid, over a 6-mo time-period in patients with generalized aggressive periodontitis. Material and Methods:  Thirty-two patients with generalized aggressive periodontitis were included in this randomized, double-blind, placebo-controlled, parallel-arm study. They were randomly assigned to azithromycin or placebo groups (500 mg once daily for 3 d). Probing depth, clinical attachment levels, presence of bleeding on probing and plaque were recorded. Gingival crevicular fluid samples were obtained from one single-rooted tooth, while microbiological samples were obtained from two single-rooted teeth, all with a probing depth of ≥ 6 mm. Microbiological parameters were analyzed by quantitative real-time PCR for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum, Prevotella intermedia and total bacteria. Gingival crevicular fluid biomarkers were determined by immunofluorometric assay and ELISA. Results:  All clinical parameters improved, and microbiological parameters and gingival crevicular fluid MMP-8 levels significantly decreased, over the 6-mo period (p < 0.05); both groups demonstrated similar improvements. The azithromycin group presented a higher percentage of deep pockets resolved (probing depth reduction of ≥ 3 mm from baseline) compared with the placebo group at 1 mo (p < 0.05). Conclusion:  Adjunctive azithromycin therapy provides no additional benefit over nonsurgical periodontal treatment on clinical parameters, microbiological parameters and gingival crevicular fluid biochemical markers investigated in patients with generalized aggressive periodontitis.

Concepts: Periodontology, Gingiva, Placebo, Periodontitis, Dentistry, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Aggressive periodontitis

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Chronic periodontitis is a silent infectious disease prevalent worldwide and affects lifestyle-related diseases. Therefore, efficient screening of patients is essential for general health. This study was performed to evaluate prospectively the diagnostic utility of a blood IgG antibody titer test against periodontal pathogens. Oral examination was performed, and IgG titers against periodontal pathogens were measured by ELISA in 1,387 individuals. The cut-off value of the IgG titer was determined in receiver operating characteristic curve analysis, and changes in periodontal clinical parameters and IgG titers by periodontal treatment were evaluated. The relationships between IgG titers and severity of periodontitis were analyzed. The best cut-off value of IgG titer against Porphyromonas gingivalis for screening periodontitis was 1.682. Both clinical parameters and IgG titers decreased significantly under periodontal treatment. IgG titers of periodontitis patients were significantly higher than those of healthy controls, especially in those with sites of probing pocket depth over 4 mm. Multiplied cut-off values were useful to select patients with severe periodontitis. A blood IgG antibody titer test for Porphyromonas gingivalis is useful to screen hitherto chronic periodontitis patients (ClinicalTrials.gov number NCT01658475).

Concepts: Immune system, Antibody, Medicine, Epidemiology, Disease, Infectious disease, Periodontitis, Porphyromonas gingivalis

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PURPOSE: Neutrophils have been shown to be involved in all stages of human and experimental abdominal aortic aneurysm (AAA) development. The initial processes of neutrophil rolling and trapping in the intraluminal thrombus (ILT) are mediated mainly by P-selectin expressed by activated platelets. In the present study, we propose to evaluate the beneficial effect of fucoidan, a competitive binding agent of P-selectin, on aneurysmal growth in a rat model of aortic aneurysm with neutrophil enrichment of the ILT induced by repeated episodes of weak bacteremia. METHODS: Sixty Lewis rats with experimental AAAs, developed from decellularized aortic xenografts, were divided into four groups. Two groups were used as controls: group fucoidan control (FC) was treated with 200 mg of fucoidan (F) delivered by 2 mL, 4-week osmotic pumps placed intraperitoneally before closing the abdomen, and group C received saline instead of fucoidan. Two more groups were injected weekly with Porphyromonas gingivalis (P. gingivalis [Pg]): group F+Pg received 200 mg of intraperitoneal fucoidan and group Pg received saline. AAAs were harvested after 4 weeks and peripheral blood was sampled at that time. Cell-free DNA (cf-DNA) and myeloperoxydase (MPO) antigen concentrations were determined in plasma and in AAA-conditioned media. Histology and P-selectin immunostaining were performed on AAA tissue samples. RESULTS: Comparing rats injected with Pg, those receiving fucoidan presented reduced aneurysmal diameter. Histologic analysis of AAAs showed that fucoidan reduced the ILT thickness in Pg-injected rats, with fewer trapped neutrophils, and with signs of a healing process, as observed in control group C. Immunohistological analysis revealed a substantial decrease in P-selectin immunostaining at the luminal surface of aneurysms in fucoidan-treated rats compared to the other groups, suggesting an interaction between fucoidan and P-selectin. A significant decrease in MPO concentrations in both plasma and conditioned medium was induced by fucoidan treatment in Pg-injected rats, reflecting a pacification of the ILT biological activity. This effect was associated with a reduction in neutrophil activation and apoptosis, reflected by a significant decrease in cf-DNA concentration in both plasma and conditioned medium of fucoidan-treated rats. CONCLUSIONS: Our results suggest that fucoidan has a beneficial effect on experimental aneurysmal degeneration by decreasing neutrophil activation in the ILT enhanced by weak pathogen contamination. This effect seems to be related to its interaction with P-selectin, which may decrease the trapping of neutrophils into the ILT. Fucoidan could represent a therapeutic option in AAAs to decrease the neutrophil activation involved in the degenerative process of aneurysmal expansion and rupture.

Concepts: Blood, Histology, Aortic aneurysm, Aneurysm, Aortic dissection, Abdominal aortic aneurysm, Aneurysm of sinus of Valsalva, Porphyromonas gingivalis

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The study aims to evaluate the change of related subgingival periodontopathogens among different stage of gingivitis in adolescent and assess the relationship between periodontopathogens and the progression of periodontal inflammation.

Concepts: Porphyromonas gingivalis

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The present clinical study aimed to investigate if there are differences in microbiological outcomes dependent on the subgingival biofilm collection method. Subgingival biofilm samples were collected from the four deepest pockets (>5 mm) of 17 patients with aggressive periodontitis (AgP) and 33 patients with chronic periodontitis (CP), first by paper point and thereafter by curette. Samples obtained with the same method were pooled together from each patient and forwarded for molecular microbiological analysis by a commercially available assay (IAI Pado Test 4.5) that estimates total bacterial load and levels of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola and Aggregatibacter actinomycetemcomitans. Data analysis included frequency of detection, quantification and correlation of detection levels between the two sampling methods. P. gingivalis, T. forsythia and T. denticola were detected in >90% of the samples, and their detection levels exhibited a strong correlation between sampling methods. The detection consistency of A. actinomycetemcomitans was 56% between the two sampling methods. A. actinomycetemcomitans was more readily detected by paper point compared with curette collection with a stronger correlation between the two methods in AgP. Subgingival biofilm sampling by curette or paper point does not yield differences in the detection of the three ‘red complex’ species. However, A. actinomycetemcomitans was more consistently detected by means of paper point collection, which can be crucial in the decision to administer antibiotics as an adjunctive periodontal treatment.

Concepts: Bacteria, Microbiology, Periodontology, Periodontitis, Dentistry, Porphyromonas gingivalis, Oral microbiology, Aggregatibacter actinomycetemcomitans

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The aim of the present study was to analyze the occurrence of Porphyromonas gingivalis (P. gingivalis), Tannerella forsythia (T. forsythia), Treponema denticola (T. denticola), and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) in patients with diabetes.

Concepts: Porphyromonas gingivalis, Oral microbiology, Aggregatibacter actinomycetemcomitans

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Objective: To evaluate the changes in the clinical parameters, and the prevalence and quantities of three major periodontopathic bacteria, namely Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Tannerella forsythia, in subgingival plaque collected from patients with generalized chronic periodontitis (GCP) or generalized aggressive periodontitis (GAgP) in response to nonsurgical periodontal therapy. Method and Materials: 73 GCP patients and 57 GAgP patients were enrolled in this study. Clinical parameters, including probing depth (PD), clinical attachment loss (CAL), and Sulcus Bleeding Index (SBI) were measured. The prevalence and quantities of the three bacteria collected from the subgingival plaque were detected by real-time PCR. Both clinical and microbiologic parameters were evaluated at baseline, 4, and 12 weeks after the nonsurgical periodontal treatment. Results: PD, CAL, and SBI were significantly improved in GCP and GAgP groups at 4 and 12 weeks after nonsurgical periodontal therapy, compared to the baseline levels. The prevalence and quantities of P gingivalis in GCP at baseline (82.19% and 3.35E+5) were statistically higher than those found in GAgP (66.67% and 1.08E+5; P < .05). After therapy, the prevalence and quantities of the three bacteria were sufficiently reduced in both groups at 4 and 12 weeks. There was no significant difference in improvement of clinical and microbiologic parameters between the GCP and GAgP patients after treatment. Conclusion: There was a difference in P gingivalis prevalence and quantity between the GCP and GAgP patients at baseline. In addition, nonsurgical periodontal therapy was effective in the treatment of clinical symptoms and the major periodontopathic bacterial control between GCP and GAgP patients.

Concepts: Statistical significance, Periodontology, Periodontitis, Dentistry, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Aggressive periodontitis, Porphyromonas

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BACKGROUND: Generalized aggressive periodontitis (GAP) is a multifactorial disease that shows a specific microbial profile and a familial aggregation. AIM: This study evaluated the salivary microbial profile of families with a history of GAP and compared them with healthy families. DESIGN: Fifteen families with parents presenting periodontal health and 15 with parents with a history of GAP were selected. Each family had a child aged 6-12 years. Stimulated saliva was collected from all subjects, and Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), and Aggregatibacter actinomycetemcomitans (Aa) amounts were determined. RESULTS: Children of GAP families showed higher detection of Aa (90%) than children of healthy families (45%) (P < 0.05). Parents with GAP showed a Pg salivary concentration statistically higher than that of healthy parents (P < 0.05).Children of GAP families, however, exhibited similar Pg concentration than healthy children (P > 0.05). Tf amounts did not differ either in parents or in children (P > 0.05) The infection risk calculation indicates that children who have one parent who is positive for Aa have 16.3 times (95% CI 3.1-87.2) more risk of being infected with Aa (P < 0.05) than children from an Aa-negative family. CONCLUSION: It may be concluded that children of parents with aggressive periodontitis have higher levels and higher risk of Aa infection.

Concepts: Family, Periodontology, Mother, Periodontitis, Dentistry, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Aggressive periodontitis

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Porphyromonas gingivalis is considered as a major etiological agent in periodontal diseases and implied to result in gingival inflammation under orthodontic appliance. rag locus is a pathogenicity island found in Porphyromonas gingivalis. Four rag locus variants are different in pathogenicity of Porphyromonas gingivalis. Moreover, there are different racial and geographic differences in distribution of rag locus genotypes. In this study, we assessed the prevalence of Porphyromonas gingivalis and rag locus genotypes in 102 gingival crevicular fluid samples from 57 cases of gingivitis patients with orthodontic appliances, 25 cases of periodontitis patients and 20 cases of periodontally healthy people through a 16S rRNA-based PCR and a multiplex PCR. The correlations between Porphyromona.gingivalis/rag locus and clinical indices were analyzed. The prevalence of Porphyromonas gingivalis and rag locus genes in periodontitis group was the highest among three groups and higher in orthodontic gingivitis than healthy people (p<0.01). An obviously positive correlation was observed between the prevalence of Porphyromonas gingivalis/rag locus and gingival index. rag-3 and rag-4 were the predominant genotypes in the patients of orthodontic gingivitis and mild-to-moderate periodontitis in Shandong. Porphyromonas.gingivalis carrying rag-1 has the strong virulence and could be associated with severe periodontitis.

Concepts: Genetics, Gingiva, Correlation and dependence, Periodontitis, Periodontal disease, Porphyromonas gingivalis, Oral hygiene, Gingivitis

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To explore whether subjects harboring Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Porphyromonas gingivalis (P. gingivalis) or Tannerella forsythia (T. forsythia) at baseline showed increased clinical benefits with the adjunctive use of systemic amoxicillin and metronidazole (AMX-MET) during non-surgical treatment of generalized aggressive periodontitis (GAgP).

Concepts: Randomized controlled trial, Periodontology, Pharmaceutical industry, Clinical research, Dentistry, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Aggressive periodontitis