Real-Time PCR Method as Diagnostic Tool for Detection of Periodontal Pathogens in Patients with Periodontitis.

The most common type of periodontal disease is chronic periodontitis, an inflammatory condition caused by pathogenic bacteria in subgingival plaque. The aim of our study was the development of a real-time PCR test as a diagnostic tool for the detection and differentiation of five periodontopathogenic bacteria, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, and Treponema denticola, in patients with periodontitis. We compared the results of our in-house method with the micro-IDent® semiquantitative commercially available test based on the PCR hybridization method. DNA was isolated from subgingival plaque samples taken from 50 patients and then analyzed by both methods. Comparing the results of the two methods, they show a specificity of 100% for all bacteria. The sensitivity for A. actinomycetemcomitans was 97.5%, for P. gingivalis 96.88%, and for P. intermedia 95.24%. The sensitivity for Tannerella forsythia and T. denticola was 100%. The Spearman correlation factor of two different measurements was 0.976 for A. actinomycetemcomitans, 0.967 for P. gingivalis, 0.949 for P. intermedia, 0.966 for Tannerella forsythia, and 0.917 for T. denticola. In conclusion, the in-house real-time PCR method developed in our laboratory can provide information about relative amount of five bacterial species present in subgingival plaque in patients with periodontitis. It is likely that such a test could be used in dental diagnostics in assessing the efficacy of any treatment to reduce the bacterial burden.

The role of probiotics for preventing dysbiosis in periodontal disease: a randomized controlled trial.

Background/aim: Scaling and root planing remain inadequate in periodontitis treatment caused by dysbiotic microbial dental plaque. The aim of this clinical trial is to evaluate the effects of probiotics and kefir consumption in initial periodontal therapy (IPT) on oral microbiota composition and treatment outcomes in patients with periodontitis. Materials and methods: The study was carried out in the Gazi University Department of Periodontology, including a sample size of 36 individuals and utilizing a randomized controlled design. Thirty-six patients with periodontitis were randomly allocated to three groups: one receiving probiotic treatment, another receiving kefir, and a third serving as the control group. Obtaining subgingival microbial samples, we recorded plaque, gingival index, bleeding on probing, periodontal pocket depth, and clinical attachment level (periodontal clinical indices) and then performed IPT. For 14 days, patients took either probiotics, kefir, or no supplements. Data for the first and third months were collected using periodontal clinical indices. DNA sequencing was performed to detect Tannerella forsythia, Porphyromonas gingivalis, and Treponema denticola in subgingival plaque samples collected at baseline and three months. Results: Significant differences were observed regarding periodontal clinical indices among groups in the intragroup comparisons. Moreover, levels of Tannerella forsythia were significantly decreased in all groups. Conclusion: Kefir can be administered in addition to IPT, providing results similar to those observed with probiotics.

A Novel Approach to the Treatment and Prevention of Alzheimer's Disease Based on the Pathology and Microbiology.

Utilizing the pathology and microbiology found in tissue from patients with documented Alzheimer's disease (AD), the pathogenesis of this fateful disorder has been made clear. Borrelia burgdorferi and Treponema denticola spirochetes enter the brain, mostly via neuronal pathways and the entorhinal circulation. These organisms easily pass through the blood-brain barrier and have an affinity for neural tissue. Once in the brain, the spirochetes make intra- and extracellular biofilms, and it is the biofilms that create the pathology. Specifically, it is the intracellular biofilms that are ultimately responsible for neurofibrillary tangles and dendritic disintegration. The extracellular biofilms are responsible for the inflammation that initially is generated by the first responder, Toll-like receptor 2. The hypothesis that arises from this work is two-pronged: one is related to prevention; the other to treatment. Regarding prevention, it is very likely possible that AD could be prevented by periodic administration of penicillin (PCN), which would kill the spirochetes before they made biofilms; this would prevent the disease and would not allow any of the above deleterious changes generated by the biofilms to occur. As regards treatment, it may be possible to slow or prevent further decline in early AD by administration of PCN together with a biofilm disperser. The disperser would disrupt the biofilm coating and enable the PCN to kill the spirochetes. This protocol could be administered in a trial with the control arm utilizing the current treatment. The progress of the treatment could be evaluated by one of the current blood tests that is semi-quantitative. The specific protocols are listed.

The first study to detect co-infection of Entamoeba gingivalis and periodontitis-associated bacteria in dental patients in Taiwan.

Periodontitis, an inflammatory disease of the oral cavity, was caused by microbes from bacteria to protozoa. In this study, we detected protozoa, Entamoeba gingivalis and other three common pathogenic bacteria, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia by the Polymerase chain reaction (PCR) on patients.

Oral infectious bacteria in dental plaque and saliva as risk factors in patients with esophageal cancer.

BACKGROUND: High levels of periodontopathic bacteria as well as Streptococcus anginosus were detected in cancer tissue from patients with esophageal cancer. An association between oral infectious bacteria and esophageal cancer has been reported. METHODS: Characteristics of the oral microbiota and periodontal conditions were studied as clinicopathologic factors in patients with esophageal cancer. The study included 61 patients with esophageal cancer and 62 matched individuals without any cancers. Samples of subgingival dental plaque and unstimulated saliva were collected to evaluate the prevalence and abundance of the following oral bacteria using a real-time polymerase chain reaction assay: Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, Treponema denticola, and S. anginosus. RESULTS: In the cancer group, the prevalence of all bacteria, with the exception of F. nucleatum, in dental plaque; the prevalence of A. actinomycetemcomitans in saliva; the abundance of all bacteria, with the exception of F. nucleatum and P. intermedia, in dental plaque; and the abundance of A. actinomycetemcomitans and S. anginosus in saliva were significantly higher. Furthermore, a logistic regression analysis suggested that the prevalence of T. forsythia and S. anginosus in dental plaque and of A. actinomycetemcomitans in saliva, as well as a drinking habit, were associated with a high risk of esophageal cancer, with a high odds ratio. CONCLUSIONS: The current findings have potential implications for the early diagnosis of esophageal cancer.

Epigenetic regulation of inflammation in periodontitis: cellular mechanisms and therapeutic potential.

Epigenetic mechanisms, namely DNA and histone modifications, are critical regulators of immunity and inflammation which have emerged as potential targets for immunomodulating therapies. The prevalence and significant morbidity of periodontitis, in combination with accumulating evidence that genetic, environmental and lifestyle factors cannot fully explain the susceptibility of individuals to disease development, have driven interest in epigenetic regulation as an important factor in periodontitis pathogenesis. Aberrant promoter methylation profiles of genes involved in inflammatory activation, including TLR2, PTGS2, IFNG, IL6, IL8, and TNF, have been observed in the gingival tissue, peripheral blood or buccal mucosa from patients with periodontitis, correlating with changes in expression and disease severity. The expression of enzymes that regulate histone acetylation, in particular histone deacetylases (HDACs), is also dysregulated in periodontitis-affected gingival tissue. Infection of gingival epithelial cells, gingival fibroblasts and periodontal ligament cells with the oral pathogens Porphyromonas gingivalis or Treponema denticola induces alterations in expression and activity of chromatin-modifying enzymes, as well as site-specific and global changes in DNA methylation profiles and in histone acetylation and methylation marks. These epigenetic changes are associated with excessive production of inflammatory cytokines, chemokines, and matrix-degrading enzymes that can be suppressed by small molecule inhibitors of HDACs (HDACi) or DNA methyltransferases. HDACi and inhibitors of bromodomain-containing BET proteins ameliorate inflammation, osteoclastogenesis, and alveolar bone resorption in animal models of periodontitis, suggesting their clinical potential as host modulation therapeutic agents. However, broader application of epigenomic methods will be required to create a comprehensive map of epigenetic changes in periodontitis. The integration of functional studies with global analyses of the epigenetic landscape will provide critical information on the therapeutic and diagnostic potential of epigenetics in periodontal disease.

Hyperbaric oxygen therapy for the treatment of moderate to severe periodontitis: a clinical pilot study.

Objectives: To clinically and microbiologically evaluate the effects of hyperbaric oxygen (HBO2) therapy in addition to full-mouth ultrasonic subgingival debridement (FM-UD), in the initial treatment of chronic periodontitis. Methods: Twenty patients presenting moderate to severe generalized forms of chronic periodontitis were included in a three-month randomized, parallel-group, single-blinded, prospective study. At baseline patients were randomly assigned to two treatment groups [Test Group (FM-UD+HBO2) and Control Group (FM-UD)]. Both groups were treated with an FM-UD session. Ten HBO2 sessions (one session per day for 10 days at a pressure of 2.5 ATA) were additionally administered to the Test Group. Soft tissues parameters [probing pocket depth (PPD), bleeding on probing (BOP), clinical attachment level (CAL) and visible plaque index (VPI)] were assessed at baseline (immediately before FM-UD treatment), after two weeks, after six weeks and at three months. For each patient, a site presenting PPD ≥ 6mm and positive BOP was selected as a qualifying site (QS), to be monitored clinically (at T0, T1, T2 and T3) and microbiologically (at T0, T1 and T3). Results: There were no statistically significant differences between the two groups for any clinical parameter analyzed after three months, except for BOP, which was significantly (p < 0.05) reduced in the Test Group. Reductions in bacterial levels were detected in both groups after therapy. Faster bacterial recolonization occurred after three months in the Control Group. Conclusion: HBO2 therapy in combination with FM-UD may represent an efficacious approach to the treatment of moderate to severe forms of periodontitis.

Clinical and microbiological evaluation of non-surgical periodontal therapy in obese and non-obese individuals with periodontitis: a 9-month prospective longitudinal study.

Objective Obesity is a chronic disease that negatively affects an individual's general and oral health. The present study aimed to compare the clinical and microbiological effects of non-surgical periodontal therapy with the full mouth disinfection (FMD) protocol on obese and non-obese individuals at 9 months post-therapy. Methodology This clinical study was first submitted and approved by the Ethics Committee. Fifty-five obese patients and 39 non-obese patients with periodontitis were evaluated. The full-mouth periodontal clinical parameters, clinical attachment level (CAL), probing depth (PD), gingival index (GI), and plaque index (PI), were monitored at baseline, 3, 6, and 9 months after periodontal treatment with full mouth disinfection (FMD) protocol. The mean count of Tannerella forsythia , Porphyromonas gingivalis , Treponema Denticola , and Aggregatibacter actinomycetemcomitans was determined by quantitative polymerase chain reaction on subgingival biofilm samples. Demographic data were assessed by Chi-square test. For clinical and microbiological parameters, two-factor repeated-measures ANOVA was used. Results In both groups, periodontal therapy using the one-stage full-mouth disinfection protocol significantly improved CAL, PD, GI, and PI (p<0.05). Obese and non-obese patients equally responded to non-surgical periodontal therapy (p>0.05). Microbial count found no major differences (p>0.05) between obese and non-obese individuals who had undergone non-surgical periodontal therapy. Conclusions Obesity did not affect the clinical and microbiological outcomes of non-surgical periodontal therapy.

The effect of periodontal bacteria infection on incidence and prognosis of cancer: A systematic review and meta-analysis.

BACKGROUND: Periodontal bacteria is the major pathogens in the oral cavity and the main cause of adult chronic periodontitis, but their association with incidence and prognosis in cancer is controversial. The aim of this study was to evaluate the effect of periodontal bacteria infection on incidence and prognosis of cancer. METHODS: A systematic literature search of PubMed, Embase, Web of Science, and Cochrane Library databases was performed to obtain 39 studies comprising 7184 participants. The incidence of cancer was evaluated as odd ratios (OR) with a 95% confidence interval (95% CI) using Review Manager 5.2 software. Overall survival, cancer-specific survival and disease-free survival, which were measured as hazard ratios (HR) with a 95% CI using Review Manager 5.2 software. RESULTS: Our results indicated that periodontal bacteria infection increased the incidence of cancer (OR = 1.25; 95%CI: 1.03-1.52) and was associated with poor overall survival (HR = 1.75; 95% CI: 1.40-2.20), disease-free survival (HR = 2.18; 95%CI: 1.24-3.84) and cancer-specific survival (HR = 1.85, 95%CI: 1.44-2.39). Subgroup analysis indicted that the risk of cancer was associated with Porphyromonas gingivalis (Pg) infection (OR = 2.16; 95%CI: 1.34-3.47) and Prevotella intermedia (Pi) infection (OR = 1.28; 95%CI: 1.01-1.63) but not Tannerella forsythia (Tf) (OR = 1.06; 95%CI: 0.8-1.41), Treponema denticola (Td) (OR = 1.30; 95%CI: 0.99-1.72), Aggregatibacter actinomycetemcomitans (Aa) (OR = 1.00; 95%CI: 0.48-2.08) and Fusobacterium nucleatum (Fn) (OR = 0.61; 95%CI: 0.32-1.16). CONCLUSION: This meta-analysis revealed periodontal bacteria infection increased the incidence of cancer and predicted poor prognosis of cancer.

[Creation of a molecular genetic test system for early diagnosis and evaluation of the effectiveness of treatment of inflammatory periodontal diseases.]

Inflammatory periodontal diseases represent a serious dental and general medical problem due to the high prevalence among the adult population, the presence of clinical forms leading to the destruction of the dentition and tooth loss, insufficient treatment effectiveness and the frequency of relapse, including in connection with the formation of biofilms. A molecular genetic test system has been developed to evaluate the content of periodontopathogenic microorganisms Porphyromonas gingivalis, Treponema denticola, Streptococcus oralis, Streptococcus sanguis and Streptococcus sobrinus in the contents of periodontal pockets. The analytical characteristics of the test system were determined, and testing was carried out on clinical samples of patients with chronic generalized periodontitis of moderate severity. The constructed diagnostic kit allowed us to conduct a comparative analysis of the effectiveness of various types of treatment of inflammatory periodontal diseases based on quantitative data on the content of bacteria in the contents of periodontal pockets.

Development of Oral Care Chip, a novel device for quantitative detection of the oral microbiota associated with periodontal disease.

Periodontal disease, the most prevalent infectious disease in the world, is caused by biofilms formed in periodontal pockets. No specific bacterial species that can cause periodontitis alone has been found in any study to date. Several periodontopathic bacteria are associated with the progress of periodontal disease. Consequently, it is hypothesized that dysbiosis of subgingival microbiota may be a cause of periodontal disease. This study aimed to investigate the relationship between the subgingival microbiota and the clinical status of periodontal pockets in a quantitative and clinically applicable way with the newly developed Oral Care Chip. The Oral Care Chip is a DNA microarray tool with improved quantitative performance, that can be used in combination with competitive PCR to quantitatively detect 17 species of subgingival bacteria. Cluster analysis based on the similarity of each bacterial quantity was performed on 204 subgingival plaque samples collected from periodontitis patients and healthy volunteers. A significant difference in the number of total bacteria, Treponema denticola, Campylobacter rectus, Fusobacterium nucleatum, and Streptococcus intermedia bacteria in any combination of the three clusters indicated that these bacteria gradually increased in number from the stage before the pocket depth deepened. Conversely, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, and Streptococcus constellatus, which had significant differences only in limited clusters, were thought to increase in number as the pocket depth deepened, after periodontal pocket formation. Furthermore, in clusters where healthy or mild periodontal disease sites were classified, there was no statistically significant difference in pocket depth, but the number of bacteria gradually increased from the stage before the pocket depth increased. This means that quantitative changes in these bacteria can be a predictor of the progress of periodontal tissue destruction, and this novel microbiological test using the Oral Care Chip could be effective at detecting dysbiosis.

Gingival crevicular fluid levels of SLIT3 are increased in periodontal disease.

This study aims to investigate the levels of SLIT3 in gingival crevicular fluid (GCF) of healthy and periodontal disease subjects, and their correlations to periodontal disease. A total of 45 periodontal patients and 45 periodontally healthy volunteers were enrolled. The clinical parameters, radiographic bone loss and the levels of SLIT3, receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) in GCF were measured. The prevalences of Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia in subgingival plaque were also analyzed. The expression of SLIT3 and RANKL was detected in the periodontium of experimental periodontitis in rats and lipopolysaccharide (LPS)-induced mouse macrophage. The total amounts and concentrations of SLIT3 and RANKL were significantly higher in periodontitis than those in healthy, while the level of OPG was significantly lower (p < .05). Significant positive correlations were observed between the level of GCF SLIT3 and clinical attachment level and radiographic bone loss (p < .05). There existed a significant positive correlation between SLIT3 and RANKL (p < .05). Increased expression of SLIT3 and RANKL was observed in the periodontium of periodontal rats. SLIT3 expression was induced by LPS stimulation in macrophages. These results suggest that SLIT3 may act as a diagnostic indicator of periodontal disease and should be further investigated.

Clinical and microbiological evaluation of non-surgical periodontal therapy in obese and non-obese individuals with periodontitis: a 9-month prospective longitudinal study

Abstract Objective Obesity is a chronic disease that negatively affects an individual's general and oral health. The present study aimed to compare the clinical and microbiological effects of non-surgical periodontal therapy with the full mouth disinfection (FMD) protocol on obese and non-obese individuals at 9 months post-therapy. Methodology This clinical study was first submitted and approved by the Ethics Committee. Fifty-five obese patients and 39 non-obese patients with periodontitis were evaluated. The full-mouth periodontal clinical parameters, clinical attachment level (CAL), probing depth (PD), gingival index (GI), and plaque index (PI), were monitored at baseline, 3, 6, and 9 months after periodontal treatment with full mouth disinfection (FMD) protocol. The mean count of Tannerella forsythia , Porphyromonas gingivalis , Treponema Denticola , and Aggregatibacter actinomycetemcomitans was determined by quantitative polymerase chain reaction on subgingival biofilm samples. Demographic data were assessed by Chi-square test. For clinical and microbiological parameters, two-factor repeated-measures ANOVA was used. Results In both groups, periodontal therapy using the one-stage full-mouth disinfection protocol significantly improved CAL, PD, GI, and PI (p<0.05). Obese and non-obese patients equally responded to non-surgical periodontal therapy (p>0.05). Microbial count found no major differences (p>0.05) between obese and non-obese individuals who had undergone non-surgical periodontal therapy. Conclusions Obesity did not affect the clinical and microbiological outcomes of non-surgical periodontal therapy.

Detection of periodontal pathogens in mothers of preterm birth and/or low weight

BACKGROUND: The present study aims to estimate the possible relationship between periodontal pathogens in the oral cavity and the birth of Preterm Birth (PTB) and/or Low Birth Weight (LBW). MATERIAL AND METHODS: It's a case- control study with the subgengival biofilm samples were collected from four sites up deeper until 48 hours postpartum and were processes by Polymerase Chain Reaction (PCR) for presence the periodontal pathogens Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn), Porphyromonas gingivalis (Pg), Treponema denticola (Td), Tannerella forsythia (Tf) e Aggregatibacter actinomycetemcomitans (Aa). The mothers were divided into case grup (babies weighing < 2500 g and/or gestational age < 37 weeks) and control group (babies weighing ≥ 2500 g and gestational age ≥ 37 weeks). Chi-square test and the measure of association obtained by Odds Ratio (OR) were used to estimate the association between the variables. RESULTS: Microbial analyses results showed no significant association between PTB and LBW with most periodontal pathogens in the oral cavity, even with association with the clinical presence of periodontitis. CONCLUSIONS: given the high presence of periodontal pathogens in the biofilm subgengival of recent mothers, it is suggested that the findings of this research serve as the basis for future studies on the pathophysiology involved in the relationship between periodontitis and PTB and/or LBW

No disponible

Evaluation of halitosis in adult patients after treatment with photodynamic therapy associated with periodontal treatment: Protocol for a randomized, controlled, single-blinded trial with 3-month follow up.

RATIONALE: Halitosis is an unpleasant odor that emanates from the mouth. Studies show halitosis returns in a week, after treatment with PDT. Probably, bacteria living in the periodontal sulcus could recolonize the dorsum of the tongue. Until nowadays, there are no study in adult population that associates halitosis and periodontal treatment with follow-up evaluation. The aim of this randomized, controlled, single-blinded clinical trial is to treat oral halitosis in healthy adults with photodynamic therapy (PDT), associated with periodontal treatment and follow them up for 3 months. PATIENT CONCERNS:: the concerns assessments will be done over the study using anamnesis interviews and specific questionnaire. DIAGNOSES:: halitosis will be evaluated by OralChroma. INTERVENTIONS: The participants (n = 40) with halitosis will be randomized into 2 groups: G1-treatment with PDT (n = 20) or G2-cleaning of the tongue with a tongue scraper (n = 20). OUTCOMES: Halitosis will be evaluated by measuring volatile sulfur compounds using gas chromatography. After the treatments, a second evaluation will be performed, along with a microbiological analysis (RT-PCR) for the identification of the bacteria T. denticola. The assessment of halitosis and the microbiological analysis will be repeated. After that, patients will receive periodontal treatment. The participants will return after 1 week and 3 months for an additional evaluation. Quality of life will be measured by Oral Health Impact Profile questionnaire (OHIP-14). LESSONS: This protocol will determine the effectiveness of phototherapy regarding the reduction of halitosis in adults. clinicaltrials.gov NCT03996915. ETHICS AND DISSEMINATION: This protocol received approval from the Human Research Ethics Committee of Universidade Nove de Julho (certificate number: 3.257.104). The data will be published in a peer-reviewed periodical.

Identification of Periopathogenes from Dental Plaque in Periodontal Patients with PCR Technique and Their Association with Composite Interleukin-1 Genotype.

INTRODUCTION: The present study aimed to assess the presence of main types of microorganisms involved in the aetiopathogenesis of chronic periodontitis with PCR technique and determinates the presence of composite IL-1 genotype and their associations with founded bacteria. MATERIAL AND METHOD: The examined group was consisted from 20 subjects with diagnosed chronic periodontitis and 20 healthy control without periodontitis. Clinical parameters like gingival index (GI), plaque index (PI), bleeding on probing (BOP), periodontal pocket depth (PPD) and clinical attachment lost (CAL) were determinates. Subgingival dental plaque was collected using a sterilized paper point. We used Parodontose Plus test, reverse hybridization kit, for the detection of periodontal marker bacteria, as well as for the detection of composite Interleukin -1 Genotype Results: The most present bacterial species detected from subgingival dental plaque was Treponema denticola and Porfiromonas gingivalis which was present in 65% of examined patients. In relation to the presence of positive genotype in patients, there was no significant difference between the test and control group for p> 0.05 (p = 1.00). For χ2=8,17 (p=0,06, p<0,05) there is an association between Prevotella intermedia, and composite genotype. Between positive genotype and analyzed bacterial species A. actinomycetem comitans for p> 0.05 (p = 1.00), P. gingivalis for p> 0.05 (p = 0.16), T. Forsythia for p> 0.05 (p = 0.20), T. Denticola for p> 0.05 (p = 0.64) no association was found. CONCLUSION: This investigations confirmed the strong association of these five examined periopathogenes with periodontitis.

Prevalence of periodontal pathogenic bacteria at different oral sites of patients with tongue piercing - results of a cross sectional study.

Aim of this cross-sectional study was to investigate the prevalence of selected potentially periodontal pathogenic bacteria in different sites of patients with tongue piercing (TP) in comparison to a control group (C). Fifty participants in each group were recruited. Samples from the biofilm originating from the piercing surface (TP group), periodontal pocket, tongue as well as cheek surface were examined regarding presence of 11 selected potentially periodontal pathogenic bacteria based on polymerase-chain reaction (PCR). In the periodontal pocket of the participants, the majority of examined bacteria were more frequently detected in TP compared to C group (pi < 0.05). At tongue and cheek surface, the prevalence of Treponema denticola (P < 0.01) and Prevotella intermedia (P < 0.01) was significantly higher in TP. For the majority of bacteria, a significant correlation between TP surface and periodontal pocket was detected (P < 0.05). In conclusion TP must be considered as potentially important ecological niche and reservoir for periodontal pathogens.

Periodontal pathogenic bacteria among high school children in Saudi Arabia.

BACKGROUND: The periodontal tissues are continuously exposed to specific bacterial components that have the ability to alter many local functions. Normal endogenous infections in healthy mouths cause disease when their numbers increase significantly. OBJECTIVE: Determine the percentage of different periodontal pathogenic bacteria and their association with periodontal status. DESIGN: Cross-sectional, analytical. SETTINGS: School children of both genders in Saudi Arabia. PATIENTS AND METHODS: Clinical examination consisted of measurement of the gingival and periodontal supporting tissue including attachment loss, probing pocket depth and furcation involvement following the National Health and Nutrition Examination Survey (NHANES) and taking samples of the subgingival bacterial flora. MAIN OUTCOME MEASURES: The percentage of periodontal pathogenic bacteria and its association with periodontal status in Saudi Arabia. SAMPLE SIZE: Bacterial samples were collected from 277 subjects. RESULTS: Aggregatibacter actinomycetemcomitans was present in 21.7% of the subjects, Porphyromonas gingivalis in 21.3%; Tannerella forsythia in 10.1%; Treponema denticola in 34.7% and Prevotella inter-media in 12.3%. The red complex bacteria were found in 2.9% of the subjects. CONCLUSIONS: The percentages of bacteria varied but only T denticola was significantly associated with periodontal breakdown. In addition, the presence of more than 2 of the 5 species tested were significantly associated with tissue damage. LIMITATIONS: Cannot be generalized to all of Saudi Arabia. Larger controlled studies are needed. CONFLICT OF INTEREST: None.

All-in-one microfluidic device for on-site diagnosis of pathogens based on an integrated continuous flow PCR and electrophoresis biochip.

Current continuous flow polymerase chain reaction (CF-PCR) microfluidic chips require external precision syringe pumps and off-line methods (e.g., electrophoresis and hybridization) to detect PCR products, resulting in complex operations and possible cross-contamination and consequently CF-PCR is still confined to laboratories. Herein, a portable all-in-one microfluidic device is fabricated for rapid diagnosis of pathogens based on an integrated CF-PCR and electrophoresis biochip. A new method was proposed for automatic sample injection into the chip which can substitute the costly external precision syringe pump. It not only achieves rapid DNA amplification and on-site PCR product detection, but also realizes automatic sample injection. As an application, three periodontal pathogens (e.g., Porphyromonas gingivalis, Treponema denticola and Tannerela forsythia) were successfully amplified in the device. Treponema denticola was amplified in as short as 2'31'', and detection of PCR products was completed within 3'43''. The minimum number of bacteria that can be amplified was 125 cfu per µl. The all-in-one device has the potential to be applied in point-of-care nucleic acid testing for diseases.

[Study on periodontal status of patients with pre-diabetes].

Objective: To investigate periodontal status of patients with pre-diabetes and evaluate the prevalence of periodontal pathogens in oral cavity. Methods: All the subjects were under regular care in urban area of Beijing, including 88 subjects with normal blood glucose (normal blood glucose group), 27 pre-diabetic patients (pre-diabetic group), 58 well-controlled diabetic patients (glucose well controlled group) and 72 poor-controlled diabetic patients (glucose poor controlled group). Whole unstimulated saliva samples were collected before periodontal examination. Periodontal parameters, including plaque index (PLI), probing depth (PD), bleeding index (BI), bleeding on probing (BOP) and clinical attachment loss (CAL), were examined at mesial-buccal and distal-lingual sites of each tooth. Number of missing teeth was recorded. DNA was extracted from the salivary deposition, Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Treponema denticola (Td), Campylobacter rectus (Cr), and Prevotella nigrescens (Pn) were detected by using PCR method based on 16SrRNA. Periodontal status and prevalence and quantity of the pathogens under various blood glucose states were compared. Results: The PD scores of four groups had no statistical differences. The CAL [(2.29±1.35) mm] and the number of missing teeth[2.0 (7.0)] in pre-diabetic group were significantly lower than that in glucose poor controlled group [(3.07±1.45) mm, P=0.04 and 5.0 (10.0), P=0.04, respectively]. The number of missing teeth in pre-diabetic group [2.0 (7.0)] was significantly lower than that in glucose well controlled group [5.0 (9.0), P=0.02]. The percent of bleeding on probing [BOP(+)%] in pre-diabetic group [(63.89±20.03)%] was significantly higher than that in normal blood glucose group [(54.51±22.29)%, P=0.04] and glucose well controlled group [(53.12±21.77)%, P=0.03]. The prevalence of Pg in pre-diabetic group (81.5%) was significantly higher than that in glucose poor controlled group (54.2%, P=0.02). The prevalence of Tf in pre-diabetic group (96.3%) was significantly higher than that in glucose poor controlled group (76.4%, P=0.01). Meanwhile the quantity of Pg [1.58 (4.75)] and Tf [5.46 (7.77)] in pre-diabetic group were significantly higher than that in glucose poor controlled group [0.60 (1.87), P=0.01 and 1.63 (3.06), P<0.01, respectively]. The quantity of Pn [0.85 (1.68)] in pre-diabetic group was significantly higher than that in normal blood glucose group [0 (1.02), P=0.04]. Conclusions: Pre-diabetic patients showed severe periodontal infection and BOP(+)% than other three groups and had high risk-level of periodontitis.