Subgingival Microbial Samples Research Articles

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

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. 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. 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. Kefir can be administered in addition to IPT, providing results similar to those observed with probiotics.

Efficacy of the additional use of subgingival air-polishing with erythritol powder in the treatment of periodontitis patients: a randomized controlled clinical trial. Part II: effect on sub-gingival microbiome

ObjectivesTo date, scarce evidence exists around the application of subgingival air-polishing during treatment of severe periodontitis. The aim of this study was to evaluate the effect on the health-related and periodontitis-related subgingival microbiome of air-polishing during non-surgical treatment of deep bleeding pockets in stage III–IV periodontitis patients.Materials and methodsForty patients with stage III–IV periodontitis were selected, and pockets with probing depth (PD) 5–9 mm and bleeding on probing were selected as experimental sites. All patients underwent a full-mouth session of erythritol powder supragingival air-polishing and ultrasonic instrumentation. Test group received additional subgingival air-polishing at experimental sites. Subgingival microbial samples were taken from the maxillary experimental site showing the deepest PD at baseline. Primary outcome of the first part of the present study was the 3-month change in the number of experimental sites. Additional analysis of periodontal pathogens and other sub-gingival plaque bacteria sampled at one experimental site at baseline and 3 months following treatment was performed through a real-time quantitative PCR microarray.ResultsIn the test group, a statistical increase of some health-related species was observed (Abiotropha defectiva, Capnocytophaga sputigena, and Lautropia mirabilis), together with the decrease of pathogens such as of Actinomyces israelii, Catonella morbi, Filifactor alocis, Porphyromonas endodontalis, Sele-nomonas sputigena, Tannerella forsythia, Treponema denticola, and Treponema socranskii. In the control group, statistical significance was found only in the decrease of Filifactor alocis, Tannerella forsythia, and Treponema socranskii.ConclusionsThe addition of erythritol-chlorhexidine powder seems to cause a shift of the periodontal micro-biome toward a more eubiotic condition compared to a conventional treatment. The study was registered on Clinical Trials.gov (NCT04264624).Clinical relevanceSubgingival air-polishing could help re-establishing a eubiotic microbioma in deep bleeding periodontal pockets after initial non-surgical treatment.

Nitrate-rich diet alters the composition of the oral microbiota in periodontal recall patients.

This follow-up study evaluated microbiome changes in periodontal recall patients after consuming a nitrate-rich diet that led to a marked decrease of gingival inflammation. Subgingival microbial samples of 37 patients suffering from gingival inflammation with reduced periodontium were taken before professional mechanical plaque removal (baseline) and subsequently after 2 weeks of regularly consuming a lettuce juice beverage (day 14) containing a daily dosage of 200mg of nitrate (test group, n=18) or being void of nitrate (placebo group, n=19). Three hundred base pairs paired-end sequencing of the V3-V4 hypervariable region of the 16S rDNA was performed. At baseline, there were no significant differences about the bacterial diversity parameters between the groups (Mann-Whitney U test). After intervention in the test group, Rothia and Neisseria, including species reducing nitrate, increased significantly (negative binomial regression model). Alpha diversity decreased significantly from 115.69 ± 24.30 to 96.42 ± 24.82 aRSVs/sample (P=0.04, Wilcoxon signed-rank test), accompanied by a significant change in beta diversity (P< 0.001, PERMANOVA). In the control group, however, no genus changed significantly, and alpha-, as well as beta-diversity did not change significantly. The decrease of gingival inflammation in periodontal recall patients induced by a nitrate-rich diet is accompanied by significant compositional changes within the subgingival microbiome.

The impact of the presence of Porphyromonas gingivalis on periodontal health in a group of patients with periodontitis in Erbil

Background and objective: Chronic periodontitis is the destruction of the tooth supporting structures as a result of a complex interaction between bacteria colonizing the gingival crevice and host’s immune responses. Porphyromonas gingivalis is one of the main periodontopathogens with multiple virulence factors. The aim of this study was to investigate the detection rate of Porphyromonas gingivalis in chronic periodontitis patients versus healthy subjects using PCR assay, and its association with increased pocket depth and clinical attachment loss. Methods: Seventy subjects (35 patients with chronic periodontitis and 35 healthy subjects) meeting the inclusion criteria of this study were selected. All the subjects were clinically assessed for probing pocket depth and clinical attachment loss then subgingival microbial samples were collected using sterile paper points and analyzed for the presence of Porphyromonas gingivalis using polymerase chain reaction assay. Results: A significant difference in Porphyromonas gingivalis detection rate between chronic periodontitis and healthy groups was recorded. Porphyromonas gingivalis was significantly associated with deep pockets. The detection rate increased with the increase in the severity of the disease, although, this correlation was not statistically significant. Conclusion: A positive association was observed between Porphyromonas gingivalis and increased pocket depth. The recovery rate was higher in severe cases.

Clinical and antimicrobial efficacy of a controlled-release device containing chlorhexidine in the treatment of chronic periodontitis.

A controlled-release device (CRD) containing chlorhexidine gluconate, such as PerioCol(™)CG (Eucare Pharmaceuticals Pvt. Ltd,, Chennai, India), for subgingival application has little reported data with clinical as well as antimicrobial efficacy. This study evaluated clinical and subgingival microbial changes on using indigenously developed PerioCol™CG as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis. Forty posterior first molar sites having probing pocket depth ≥ 5 mm were selected and divided into two groups, with 20 sites in each group, in a split-mouth design. Group A (test site) was treated with SRP and PerioCol(™)CG, while group B (control site) was treated with SRP alone. Subgingival microbial samples were collected at baseline and 1 month after the initial SRP, while probing depth (PD), clinical attachment level (CAL) and gingival index (GI) were recorded at baseline, after 1 month and after 3 months. Microbial detection of Porphyromonas gingivalis (P. gingivalis) and Tannerella forsythia (T. forsythia) was done by means of polymerase chain reaction (PCR). A significant improvement was observed in all clinical measures in sites treated with PerioCol(™)CG as compared to the control sites during the study period. Also, there was a statistically significant reduction in the proportion of occurrence of P. gingivalis and T. forsythia after intervention in test sites as compared to control sites. Our data suggest that SRP combined with subgingival administration of PerioCol™CG has a significantly better and prolonged effect compared to SRP alone on the PD, clinical attachment loss and elimination of periodontopathogens.

Evaluation of Subgingival Dental Plaque Microbiota Changes In Fixed Orthodontic Patients with Syber Green Real Time PCR

Introduction: One of the most common problems we confront in orthodontic therapy is periodontal diseases. Initial factor which causes these diseases is colonization of anaerobic microorganisms in subgingival plaque. Technically, local environmental changes related to orthodontic band and brackets may influence the bacterial species in periodontal plaque. However, it seems necessary to assess variations in subgingival plaque caused by orthodontic appliances. The aim of this study was to investigate changes in subgingival microbiota and clinical parameters before and after bracket placement. Methods: Clinical parameters including probing depth (PD), plaque index (PI), clinical attachment level (CAL), bleeding on probing (BOP) and gingival index (GI) were recorded and subgingival microbial samples were collected in 30 people aged between 13 and 25. As a control group, 15 persons getting matched as to their age and sex with no need to orthodontic treatment were opted using specific primers, SYBER Green Real-Time PCR was carried out in order to determine bacterial flora in stored samples. All mentioned procedures were reassessed in experimental group and in control group three months after band and bracket bonding. A descriptive analysis was conducted, and paired t test and Wilcoxon test were used for differences between groups (P<0.05). Results: No changes in clinical attachment level were observed, but scores for bleeding on probing, plaque index, and gingival index increased 3 months after bracket placement in experimental group (P<0.05). Prevotella intermedia rose in experimental group after brackets placement compared with control group but Actinobacillus actinomycetem comitans and Tanerella forsythia proportions did increase. Conclusions: treatment with fixed appliances may transitionally raise the growth of periodontopathogenic bacteria and consequently result in gingival inflammatory response but without destructive effect on deep periodontal tissues.

Assessment of the periodontal health status in patients undergoing orthodontic treatment with fixed or removable appliances. A microbiological and preliminary clinical study

800x600 Objectives: The use of removable orthodontic appliances minimizes the negative effects on periodontal health allowing patients to carry out oral hygiene without obstacles. The aim of this preliminary study was to evaluate microbiological and clinical changes presented during the first three months of orthodontic therapy in adults with fixed appliances and Invisalign® System (Align Technology, Santa Clara, California). Materials and Methods: Plaque Index (PI), Probing Depth (PD), Bleeding on probing (BOP), Compliance to oral hygiene and subgingival microbial samples were assessed in 30 patients. Samples were analyzed by real time PCR to detect periodontal pathogens and microbial biofilm mass. A statistical comparison was made over time and amongst the three groups, using Chi-square X2, Odds Ratios (OR), Regression analysis (DOE) and ANOVA. Results: After 30 and 90 days of treatment there was only one sample with periodontopathic anaerobes found in a patient treated using fixed orthodontic appliances. Direct influence of orthodontic treatment on compliance and less subgingival biofilm mass were found with Invisalign® patients who increased the time dedicated to oral hygiene. A decrease on PD (p=0,002) and BOP (p<0,001) was detected in the Invisalign® group after 90 days of treatment. Conclusions: In this preliminary study, fixed and removable appliances did not increase the risk for periodontal disease in patients undergoing orthodontic therapy. However, the removable Invisalign® appliances may facilitate oral hygiene procedures, maintaining a lower level of microbial biofilm mass, even with poor oral hygiene compliance, minimizing the negative effects on gingival inflammation. Normal 0 21 false false false TR X-NONE X-NONE MicrosoftInternetExplorer4

Evaluation of Subgingival Microflora in All Ceramic Restorations with Subgingival Heavy Chamfer Finish Lines

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

Microbiologic changes in subgingival plaque before and during the early period of orthodontic treatment

To evaluate changes in subgingival microbiota before and during the leveling and alignment orthodontic stage using the polymerase chain reaction (PCR) method. Thirty orthodontic patients (17 females and 13 males; aged 16.7 ± 6.5 y) were included in this study. Subgingival microbial samples were taken from the disto-buccal gingival crevice of the left upper central incisors, the left lower central incisors, the mesio-buccal gingival crevice of the left upper first molars, and the left lower first molars, at four different times: at baseline, before placement of orthodontic appliances (T1), and 1 week (T2), 3 months (T3), and 6 months after placement of orthodontic appliances (T4). DNA was extracted from the samples, and the 16S rRNA-based PCR detection method was used to determine the prevalence of Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Campylobactor rectus, Eikenella corrodens, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola, which are considered as putative periodontopathogens. The frequency of T forsythia, C rectus, and P nigrescens significantly increased after placement of orthodontic appliances. For the other species, the frequency tended to increase but no statistically significant difference was noted. The frequency of the change, representing microorganisms not existing at T1 but newly developing at T2, T3, and T4, was higher at the molars than at the incisors. The placement of orthodontic appliances affects the subgingival microbial composition even during the early period of orthodontic treatment, increasing the prevalence of periodontopathogens, especially in the molar region.

Periodontitis: A Future Risk of Acute Coronary Syndrome? A Follow‐Up Study Over 3 Years

Periodontitis has been associated with cardiovascular disease. We assess if the recurrence of acute coronary syndrome (ACS) could be predicted by preceding medical and periodontal conditions. A total of 165 consecutive subjects with ACS and 159 medically healthy, matched control subjects were examined and followed for 3 years. Periodontitis was defined by alveolar bone loss. Subgingival microbial samples were studied by the checkerboard DNA-DNA hybridization method. The recurrence of ACS was found in 66 of 165 (40.0%) subjects, and a first ACS event was found in seven of 159 (4.4%) subjects among baseline control subjects. Subjects who later had a second ACS event were older (P <0.001). Significantly higher serum levels of high-density lipoprotein (P <0.05), creatinine (P <0.01), and white blood cell (WBC) counts (P <0.001) were found in subjects with future ACS. Periodontitis was associated with a first event of ACS (crude odds ratio [OR]: 10.3:1; 95% confidence interval [CI]: 6.1 to 17.4; P <0.001) and the recurrence of ACS (crude OR: 3.6:1; 95% CI: 2.0 to 6.6; P <0.001). General linear modeling multivariate analysis, controlling for age and the prediction of a future ACS event, identified that WBC counts (F = 20.6; P <0.001), periodontitis (F = 17.6; P <0.001), and serum creatinine counts (F = 4.5; P <0.05) were explanatory of a future ACS event. The results of this study indicate that recurrent ACS events are predicted by serum WBC counts, serum creatinine levels, and a diagnosis of periodontitis. Significantly higher counts of putative pathogens are found in subjects with ACS, but these counts do not predict future ACS events.

Microbiology and Cytokine Levels Around Healthy Dental Implants and Teeth

Elicitation of the relationship of periodontopathogens and pro-inflammatory cytokines to bone resorption and formation is significant to a growing body of research known as osteoimmunology. It is essential that clinically healthy peri-implant and periodontal sites are studied to contribute comparison data for investigations that are addressing diseased sites. The purpose of this study was to describe levels of selected pro-inflammatory cytokines in clinically healthy peri-implant and periodontal sites, and to examine whether cytokine levels may be related to specific bacterial/viral pathogens. Eleven subjects (mean age 56.2 +/- 10) participated in the study. Subgingival microbial samples were cultured for periodontopathic bacteria. Gingival crevicular fluid samples were analyzed by nested polymerase chain reaction for Cytomegalovirus (HCMV) and were tested for the quantification of Interleukin (IL)-8, IL-1beta, IL-6, IL-10, Tumor Necrosis Factor (TNF)-alpha, and IL-12p70 using flow cytometry (FACS). Findings for microbiota composition and cytokine levels were compared between implants and teeth (chi square, Kruskall-Wallis, Mann-Whitney; p < or = .05). Both the frequency (%) and levels (%) of periodontopathic bacteria were higher around teeth than implants. The concentration (picogram per milliliter) of cytokines was more prominent around implants than teeth, reaching nearly twofold differences in some instances. Cytokine levels were higher when the sites analyzed were positive for any bacteria tested. HCMV was not detected. Pro-inflammatory cytokine production was unrelated to heavy bacterial challenge. Nevertheless, when periodontopathic bacteria were detected by culture, cytokine levels were increased around both implants and teeth. Studies are needed to investigate the pro-inflammatory cytokines (especially IL-1beta and TNF-alpha) produced in spite of minimal bacterial accumulation.

Periodontal Microbiota in Patients With Coronary Artery Disease Measured by Real‐Time Polymerase Chain Reaction: A Case‐Control Study

Recent data have shown that periodontal disease may increase the risk of occurrence of coronary heart disease in which inflammation initiated by bacteria and their compounds might be a common causal factor. This case-control study aimed at studying the relationship between periodontal disease and coronary artery disease (CAD) based on clinical and periodontal microbiologic parameters. A total of 90 male subjects, 48 to 80 years of age, were included in this study. Forty-five men had CAD (CAD+), which was confirmed by coronary angiography. Forty-five age-matched controls showed no history or symptoms of CAD (CAD-). All subjects underwent a clinical periodontal examination including assessment of tooth loss, probing depth, clinical attachment level, and bleeding on probing. In the CAD+ group, this examination took place 1 day before coronary angiography. Subgingival microbial samples were taken and evaluated by means of real-time polymerase chain reaction (RT-PCR) for the total amount of bacteria and the following periodontopathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Parvimonas micra (formerly Micromonas micros), Dialister pneumosintes, and Campylobacter rectus. Compared to control subjects, CAD+ subjects had significantly deeper pockets (2.28 mm versus 2.96 mm; P <0.001) and greater attachment loss (2.85 mm versus 3.65 mm; P <0.001), and this difference remained statistically significant after adjusting for smoking. No significant differences were observed between cases and controls with regard to the number of teeth present. P. intermedia was the only periodontal pathogen that showed significantly higher mean counts in CAD+ subjects compared to CAD- subjects. Higher counts of total bacteria, P. micra, D. pneumosintes, and C. rectus were found in the CAD- group. The results suggest that a relationship between periodontal disease and coronary heart disease exists, although P. intermedia was the only periodontopathogen related to CAD.

Changes in the subgingival microbiota and periodontal parameters before and 3 months after bracket placement

Dental plaque is organized in a biofilm complex that provides protection and nutrients for periodontopathic bacteria. Several factors can affect microbial colonization, including restorations and orthodontic brackets. The aim of this study was to investigate changes in subgingival microbiota and clinical parameters before and after bracket placement. Clinical parameters and subgingival microbial samples were collected from 30 patients before and after bracket placement. Thirty additional patients with no orthodontic treatment served as controls. Samples were cultured and analyzed for periodontopathic and superinfecting bacteria. A descriptive analysis was conducted, and chi-square, Student t, Wilcoxon matched, and Mann Whitney rank sum tests were used to test for differences between groups (P < or=.05). No changes in probing depth or clinical attachment level were observed, but scores for bleeding on probing, plaque index, and gingival index increased after bracket placement (P < or =.05). Porphyromonas gingivalis, Prevotella intermedia/Prevotella nigrescens, Tannerella forsythia, and Fusobacterium species were elevated in the experimental group after bracket placement compared with the control group (P < or =.01). Superinfecting microorganisms such as Enterobacter cloacae, Klebsiella oxytoca, Klebsiella pneumoniae, and Serratia marcescens were also found. Bracket placement influences the accumulation of plaque and the colonization of important periodontopathic and superinfecting bacteria, resulting in more inflammation and bleeding. Special attention should be paid to oral hygiene methods in orthodontic patients.

Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis subgingival presence, species‐specific serum immunoglobulin G antibody levels, and periodontitis disease recurrence

The biological and clinical effects of antibody against periodontal pathogenic bacteria are incompletely understood. This study evaluated the inter-relationships among periodontal levels of cultivable Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis, species-specific serum immunoglobulin G (IgG) antibody levels, and periodontitis disease activity. Forty-three adults who had previously been treated for periodontitis and who also harbored cultivable A. actinomycetemcomitans or P. gingivalis were evaluated semiannually for clinical disease recurrence over a 36-month period. Each patient provided subgingival microbial samples, for the recovery of A. actinomycetemcomitans and P. gingivalis, from the two deepest pockets in each dentition sextant. A. actinomycetemcomitans and P. gingivalis serum IgG antibody levels were assessed using enzyme-linked immunosorbent assay (ELISA), together with whole-cell sonicate extracts from A. actinomycetemcomitans serotypes a-c and P. gingivalis ATCC 33277. Data were analyzed using the Mantel-Haenszel chi-square and Fisher exact two-tailed tests. Eighteen (60.0%) of 30 A. actinomycetemcomitans-positive subjects, and 10 (76.9%) of 13 P. gingivalis-positive subjects, exhibited recurrent periodontal breakdown within 36 months of periodontal therapy. Nineteen (67.9%) of the 28 patients with active periodontitis had A. actinomycetemcomitans or P. gingivalis serum antibody levels below designated threshold values. In comparison, 10 (66.7%) of 15 culture-positive clinically stable subjects showed A. actinomycetemcomitans or P. gingivalis serum antibody levels above threshold values. The difference between specific antibody levels in periodontitis-active and periodontitis-stable patients was statistically significant (p = 0.032). Serum levels of IgG antibodies against A. actinomycetemcomitans or P. gingivalis in periodontitis-stable patients were higher than those in patients with active periodontitis. The results suggest that elevated levels of IgG antibody against A. actinomycetemcomitans and P. gingivalis have a detectable protective effect against periodontal infections with these microorganisms.

Oral microbial ecology in chronic periodontitis and periodontal health

Our aim was to find out differences between chronic periodontitis (CP) and periodontally healthy subjects with respect to oral lactic acid bacteria (LAB) as well as subgingival microbial relations. Clinical data, salivary levels of lactobacilli and mutans streptococci, and subgingival microbial samples were obtained from 26 CP and 15 periodontally healthy subjects. Antimicrobial activity of LAB against periodontal pathogens was assessed. We found Actinobacillus actinomycetemcomitans , Porphyromonas gingivalis and Prevotella intermedia/nigrescens in 54%, 23% and 73% of CP patients, respectively; the latter was also found in 47% of healthy subjects. The mean proportion of streptococci (27.0 vs 15.2%), particularly S. mutans group (5.7 vs 0.8%) and S. mitis group (18.1 vs 5.0%), as well as aerobic coryneforms (24.7 vs 11.9%) was higher in healthy persons (p< 0.05). An inverse relationship of subgingival streptococci and aerobic coryneforms with periodontal pathogens and deteriorated clinical parameters were seen. Salivary counts of mutans streptococci were higher in healthy persons. Inhibition of periodontal pathogens by LAB was observed. In conclusion, the proportions of oral LAB were significantly lower in CP than in healthy subjects, whilst being important antagonists against periodontal pathogens. These oral commensals may play an important role in the suppression of periodontal pathogens and maintenance of microecological balance in the oral cavity. Key words: Chronic periodontitis, periodontal health, lactic acid bacteria, subgingival microflora, antimicrobial activity, microbial ecology

Oral microbial ecology in chronic periodontitis and periodontal health

Our aim was to find out differences between chronic periodontitis (CP) and periodontally healthy subjects with respect to oral lactic acid bacteria (LAB) as well as subgingival microbial relations. Clinical data, salivary levels of lactobacilli and mutans streptococci, and subgingival microbial samples were obtained from 26 CP and 15 periodontally healthy subjects. Antimicrobial activity of LAB against periodontal pathogens was assessed. We found Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia/nigrescens in 54%, 23% and 73% of CP patients, respectively; the latter was also found in 47% of healthy subjects. The mean proportion of streptococci (27.0 vs 15.2%), particularly S. mutans group (5.7 vs 0.8%) and S. mitis group (18.1 vs 5.0%), as well as aerobic coryneforms (24.7 vs 11.9%) was higher in healthy persons (p < 0.05). An inverse relationship of subgingival streptococci and aerobic coryneforms with periodontal pathogens and deteriorated clinical parameters were seen. Salivary counts of mutans streptococci were higher in healthy persons. Inhibition of periodontal pathogens by LAB was observed. In conclusion, the proportions of oral LAB were significantly lower in CP than in healthy subjects, whilst being important antagonists against periodontal pathogens. These oral commensals may play an important role in the suppression of periodontal pathogens and maintenance of microecological balance in the oral cavity.

Subgingival microflora in Turkish patients with periodontitis.

No information exists on periodontitis-associated subgingival microbiota from Turkey. We determined the occurrence, interspecies relationships, and clonal characteristics for a group of periodontal bacteria in a Turkish study population. Subgingival microbial samples were obtained from patients with localized (LAgP, N = 18) or generalized (GAgP, N = 17) types of aggressive periodontitis, generalized chronic periodontitis (GCP, N = 14), and non-periodontitis subjects (N = 20). Culture methods were used to recover 6 periodontal bacterial species and yeasts, and a polymerase chain reaction technique was used to detect Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. Intraspecies characterization of A. actinomycetemcomitans was carried out by serotyping and genotyping. All species, except for Micromonas micros (formerly Peptostreptococcus micros) occurred more frequently (P < 0.05) in periodontitis than non-periodontitis subjects. Detection frequencies for Tannerella forsythensis (formerly Bacteroides forsythus) and Campylobacter rectus differed among the periodontitis subgroups; the lowest frequency occurred in LAgP. The mean proportions of A. actinomycetemcomitans, P. gingivalis, and C. rectus were higher (P < 0.008) in GAgP than in non-periodontitis subjects. Significant positive associations were seen between 7 of the 22 possible combinations (P < 0.05). A. actinomycetemcomitans serotype c (34%) and non-serotypeable isolates (34%) were the most common antigenic types among the 305 strains analyzed. Eleven arbitrarily primed (AP)-PCR genotypes were distinguished among 273 isolates from 29 subjects. Yeasts were found in 23% of the 69 subjects. The results on the Turkish study population were generally in line with earlier reports on the occurrence and interspecies relationships of certain bacteria in periodontitis. However, A. actinomycetemcomitans was not overrepresented in LAgP, and the serotype distribution resembled that reported from the East. The high frequency of non-serotypeable isolates suggests local characteristics of the species.

Local antibiotic therapy guided by microbiological diagnosis.

The aim of this study was to determine the distribution patterns of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans in periodontitis patients after standard mechanical periodontal therapy, and to evaluate the effect of additional local antibiotic therapy, given to all teeth with cultural evidence of these bacteria. 17 patients were included. 852 separate subgingival microbial samples were taken from the mesial and distal aspect of every tooth in 17 subjects at baseline. 46 of these samples, from 10 positive subjects, showed cultural evidence for P. gingivalis. 82 samples, from 5 subjects, were A. actinomycetemcomitans-positive. Three subjects showed no evidence for persistence of A. actinomycetemcomitans or P. gingivalis. In the other 14 subjects, all A. actinomycetemcomitans- or P. gingivalis-positive teeth were treated with tetracycline fibers (ACTISITE(R)). Sub-gingival microbial samples were again taken from two sites of every tooth, 1 month after fiber removal. 89% of the initially P. gingivalis-positive sites were now negative, but 16 previously negative sites now tested positive. 77% of the initially A. actinomycetemcomitans-positive sites were now negative, but 5 previously negative sites now tested positive. The teeth with persisting P. gingivalis or A. actinomycetemcomitans were again treated with fibers. Two sites of every tooth were once more sampled after 1 month. At this time, 5 subjects still showed cultural evidence of P. gingivalis at a total of 19 sites, and 4 subjects were positive for A. actinomycetemcomitans in a total of 27 sites. These 9 patients were finally submitted to systemic antibiotic therapy (3 x 250 mg metronidazole plus 3 x 375 mg amoxicillin/d for 7 days). Despite of all efforts, P. gingivalis was again detected 3 months later in isolated sites in 3 subjects, and A. actinomycetemcomitans could be cultivated from one single site. Therapy with tetracycline fibers guided by microbiological diagnosis effectively reduced P. gingivalis and A. actinomycetemcomitans locally, but was unable to completely eradicate the target organisms. Additional systemic antibiotic therapy further reduced P. gingivalis and A. actinomycetemcomitans. The observed persistence patterns suggest that reemergence of A. actinomycetemcomitans was due to recolonization, whereas the strikingly reproducible local reemergence of P. gingivalis in some sites indicated failed eradication.

Expression of matrix metalloproteinases in healthy and diseased human gingiva.

The aim of our study was to investigate the patterns of several metalloproteinases (MMP-1, MMP-2 and MT1-MMP) mRNAs expression using a semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and to correlate them with clinical parameters and bacteriological diagnosis in healthy versus diseased human gingiva. To identify the cell origin of MMP production, in situ hybridization (ISH) was also performed for the MMPs on the same samples. 17 gingival biopsies were collected (13 affected by advanced periodontitis and 4 healthy used as controls) and plaque index, gingival index, pocket depth and bleeding on probing were measured. Subgingival microbial samples were also collected to be analysed by a DNA probe technique. The biopsies were processed both for RT-PCR and ISH. We also investigated a model for bacterial induced MMP expression in human gingival fibroblasts (HGF) infected by Eikenella corrodens. We found an expression of the mRNA encoding MMP-1 only in diseased gingiva but at low levels relative to beta-actin (mean+/-SD: diseased versus healthy: 0.013+/-0.024 versus 0). Although the frequencies and levels of mRNA encoding for MMP-2 or MT1-MMP are not significantly different between each group (mean+/-SD: 0.329+/-0.344 versus 0.137+/-0.219 for MMP-2; 0.485+/-0.374 versus 0.466+/-0.296 for MT1-MMP), using ISH, we observed an expression of both mRNAs in fibroblasts of pathological specimens at sites that histologically showed signs of chronic inflammation and connective tissue remodelling. In vitro infection of HGF by Eikenella corrodens stimulated 3-fold the production of the mRNA encoding MMP-2 while other mRNAs remained unchanged. Our results did not reveal significant differences in the expression of mRNAs encoding for the MMPs between healthy and periodontitis-affected patients, reflecting the great heterogeneity in the periodontal status of individuals. However, they indicate that gingival fibroblasts are an active source of MMP-2 production in response to a periopathogen.

Persistence patterns of Porphyromonas gingivalis, Prevotella intermedia/nigrescens, and Actinobacillus actinomyetemcomitans after mechanical therapy of periodontal disease.

The aim of this study was to determine the distribution patterns of Porphyromonas gingivalis, Prevotella intermedia/nigrescens, and Actinobacillus actinomycetemcomitans in periodontitis patients after standard mechanical periodontal therapy, and to determine factors increasing the odds to detect these target organisms in treated sites. Eight hundred fifty-two (852) separate subgingival microbial samples were taken from the mesial and distal aspects of every tooth in 17 patients. Target organisms were identified culturally. The 3 microorganisms showed different persistence patterns: P. gingivalis was detected in a high percentage of subjects (59%), but in a low proportion of sites (5.4%). P. intermedia/nigrescens was detected in all subjects except one, and in 40.6% of the tested sites. Only 5 subjects were A. actinomycetemcomitans positive, but 2 of them showed a very high number of positive sites (44% and 75%, respectively). A highly significant relationship was found between a subject's tendency to bleed upon sampling and the number of P. intermedia/nigrescens-positive sites. A significant portion of the variation in frequency of persisting P. gingivalis could be explained by the frequency of persisting pockets deeper than 4 mm. No similar relationship could be established between clinical parameters and A. actinomycetemcomitans. On a site level, the odds of detecting P. gingivalis increased by a factor of 2.47 (P= 0.0001) for every millimeter of residual probing depth; the odds of detecting P. intermedia/nigrescens increased by a factor of 1.84 (P= 0.0001). If, after standard mechanical periodontal therapy, a large number of sites continue to bleed, one may expect an increased number of sites positive for P. intermedia/ nigrescens. If many deep pockets persist, a greater number of P. gingivalis-positive sites can be expected.