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.

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.

Effect of quadrantwise versus full-mouth subgingival instrumentation on clinical and microbiological parameters in periodontitis patients: A randomized clinical trial.

AIM: This study evaluated the efficacy of quadrantwise subgingival instrumentation (Q-SI) versus one-stage full-mouth subgingival instrumentation (FM-SI) on probing depth and periodontal pathogen reduction over a 6-month follow-up period, as well as whether baseline periodontal pathogens influenced the impact of periodontal treatment protocols on outcomes. METHODS: Patients with periodontitis were randomized to receive Q-SI (n = 43) or FM-SI (n = 45). Patients were instructed and motivated to maintain optimal oral hygiene during the treatment sessions. Clinical (probing pocket depth [PPD], clinical attachment loss [CAL], and bleeding on probing [BOP]) and periodontal pathogens were assessed at baseline and after 30, 90, and 180 days. Total bacterial load and periodontal pathogens were analysed via real-time PCR. RESULTS: At the 6-month follow-up, the median PPD decreased from 4.8 mm (interquartile range [IQR]: 4.3-5.2) to 2.6 mm (IQR: 2.3-2.9) in FM-SI patients and from 4.7 mm (IQR: 4.1-5.2) to 3.2 mm (IQR: 2.4-3.5) in Q-SI patients (p < .001). At 6 months, FM-SI was more effective at reducing the median proportions of Porphyromonas gingivalis (Pg), Aggregatibacter actinocomyctemcomitans, and Tannerella forsythia (Tf) (p < .001 for each value). Multilevel linear regression analysis demonstrated that high baseline PPD (p = .029), Pg (p = .014), and Tf (p < .001) levels and the FM-SI protocol (p < .001) were statistically significant predictors of PPD reduction at 6 months. Furthermore, PPD reduction was significantly greater in the FM-SI group when lower baseline Pg levels were detected. CONCLUSION: The FM-SI was more effective than the Q-SI in reducing the mean PPD and number of periodontal pathogens in periodontitis patients over a 6-month follow-up period. Higher baseline PPD and Pg levels had a negative impact on PPD reduction at 6 months after FM-SI.

Relationship between IgA Nephropathy and Porphyromonas gingivalis; Red Complex of Periodontopathic Bacterial Species.

IgA nephropathy (IgAN) has been considered to have a relationship with infection in the tonsil, because IgAN patients often manifest macro hematuria just after tonsillitis. In terms of oral-area infection, the red complex of periodontal bacteria (Porphyromonas gingivalis (P. gingivalis), Treponema denticol (T. denticola) and Tannerella forsythia (T. forsythia)) is important, but the relationship between these bacteria and IgAN remains unknown. In this study, the prevalence of the red complex of periodontal bacteria in tonsil was compared between IgAN and tonsillitis patients. The pathogenicity of IgAN induced by P. gingivalis was confirmed by the mice model treated with this bacterium. The prevalence of P. gingivalis and T. forsythia in IgAN patients was significantly higher than that in tonsillitis patients (p < 0.001 and p < 0.05, respectively). A total of 92% of tonsillitis patients were free from red complex bacteria, while only 48% of IgAN patients had any of these bacteria. Nasal administration of P. gingivalis in mice caused mesangial proliferation (p < 0.05 at days 28a nd 42; p < 0.01 at days 14 and 56) and IgA deposition (p < 0.001 at day 42 and 56 after administration). Scanning-electron-microscopic observation revealed that a high-density Electron-Dense Deposit was widely distributed in the mesangial region in the mice kidneys treated with P. gingivalis. These findings suggest that P. gingivalis is involved in the pathogenesis of IgAN.

Latency, thermal stability, and identification of an inhibitory compound of mirolysin, a secretory protease of the human periodontopathogen Tannerella forsythia.

Mirolysin is a secretory protease of Tannerella forsythia, a member of the dysbiotic oral microbiota responsible for periodontitis. In this study, we show that mirolysin latency is achieved by a "cysteine-switch" mechanism exerted by Cys23 in the N-terminal profragment. Mutation of Cys23 shortened the time needed for activation of the zymogen from several days to 5 min. The mutation also decreased the thermal stability and autoproteolysis resistance of promirolysin. Mature mirolysin is a thermophilic enzyme and shows optimal activity at 65 °C. Through NMR-based fragment screening, we identified a small molecule (compound (cpd) 9) that blocks promirolysin maturation and functions as a competitive inhibitor (Ki = 3.2 µM), binding to the S1' subsite of the substrate-binding pocket. Cpd 9 shows superior specificity and does not interact with other T. forsythia proteases or Lys/Arg-specific proteases.

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.

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.

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.

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.

Detection of Tannerella forsythia bspA and prtH genotypes among periodontitis patients and healthy subjects-A case-Control study.

BACKGROUND: T. forsythia a gram negative, anaerobe inhabits the mature biofilm present at sites expressing progressive periodontitis. It is a part of "red complex" group which contributes to the pathogenesis of periodontitis. The BspA protein and prtH gene encoded cysteine protease play a vital role in the virulence of T. forsythia. The present study aims to detect the two genotypes (bspA and prtH) in periodontitis and healthy subjects. MATERIALS & METHOD: Subgingival plaque samples were collected from periodontitis patients and healthy subjects (Chronic Periodontitis n = 128, Aggressive Periodontitis n = 72, healthy subjects n = 200). The samples were screened for the presence of T. forsythia 16S rRNA, bspA and prtH genotypes by Polymerase Chain Reaction. The prevalence of the genotypes between periodontitis patients and healthy subjects was compared with Pearson's Chi-square test. A P value of < 0.05 was considered to be statistically significant. RESULTS: The prevalence for T. forsythia in Chronic Periodontitis (n = 128), Aggressive Periodontitis (n = 72) and health (n = 200) was 73.4%, 59.7% and 10.5% respectively. The prevalence of T.forsythia bspA/prtH genotypes was 81.90%/43.60%, 88.40%/53.50% and 33.30%/14.3% in Chronic Periodontitis, aggressive Periodontitis and health respectively. Compared to healthy subjects, the odds of detecting T.forsythia 16S rRNA was 18.53 times high in individuals with periodontitis (P = 0.0001). CONCLUSION: The high odds ratio of T.forsythia 16S rRNA among periodontitis strongly suggests its role in periodontitis. In addition, the high prevalence of T. forsythia bspA genotype among Chronic Periodontitis signifies it as a useful marker for chronic periodontitis.

Smoking habit modulates peri-implant microbiome: A case-control study.

BACKGROUND AND OBJECTIVE: Smoking is a recognized risk factor for peri-implant disease and leads to microbiological changes in mucositis and peri-implantitis. However, there is no knowledge about the impact of smoking in healthy peri-implant tissue. The aim of the study was to evaluate the microbiome in a peri-implant environment in smokers with healthy peri-implant conditions. METHODS: Peri-implant biofilm was collected around single clinically healthy, screwed-retained, teeth-surrounded implants in 12 non-smoker (NSMK) and 12 smoker (SMK) non-periodontitis subjects (no bleeding and probing depth <4 mm). Bacterial DNA was isolated and 16S ribosomal RNA gene libraries were sequenced using pyrosequencing, targeting the V3-V4 region. Datasets were processed using the Quantitative Insights into Microbial Ecology, Greengenes and the Human Oral Microbiome Database databases. RESULTS: An evident difference in the SMK peri-implant microbiome was observed compared to the NSMK microbiome, with a large abundance of species, even with a healthy peri-implant. The SMK core-microbiome showed an abundance of Fusobacterium, Tannerella and Mogibacterium, while the NSMK core revealed an abundance of Actinomyces, Capnocytophaga and Streptococcus, genera that are usually related to periodontal health. The microbiome inter-relationship was shown to be more inter-generic in SMK then in NSMK, indicating different microbiome cohesion. CONCLUSION: Smoking negatively affected the peri-implant microbiome, leading to a disease-associated state, even in clinically healthy individuals.

Effect of orthodontic treatment on the subgingival microbiota: A systematic review and meta-analysis.

The aim of this systematic review was to assess qualitative changes induced by fixed appliance orthodontic treatment on the subgingival microbiota. Seven databases were searched up to August 2017 for randomized and nonrandomized clinical studies assessing the effect of orthodontic appliances on the subgingival bacteria in human patients. After elimination of duplicate studies, data extraction and risk of bias assessment according to the Cochrane guidelines, random-effects meta-analyses of relative risks (RR) and their 95% confidence intervals (CIs) were performed. According to controlled studies, the presence of Aggregatibacter actinomycetemcomitans in the subgingival crevicular fluid of orthodontic patients was increased 3-6 months after fixed appliance insertion compared to untreated patients (2 studies; RR = 15.54; 95% CI = 3.19-75.85). There was still increased subgingival prevalence of Aggregatibacter actinomycetemcomitans (3 studies; RR = 3.98; 95% CI = 1.23-12.89) and Tannerella forsythia in orthodontic patients up to 6 months after appliance removal compared to untreated patients. However, caution is warranted due to high risk of bias and imprecision. Insertion of orthodontic fixed appliances seems to be associated with a qualitative change of subgingival microbiota, which reverts to some extent back to normal in the first months after appliance removal. However, there is limited evidence on the timing and extent of these changes.

Characterisation and pure culture of putative health-associated oral bacterium BU063 (Tannerella sp. HOT-286) reveals presence of a potentially novel glycosylated S-layer.

Tannerella HOT-286 (phylotype BU063) is a recently identified novel filamentous Gram-negative anaerobic oral bacterium cultured for the first time recently in co-culture with Propionibacterium acnes. In contrast to the related periodontal disease-associated pathobiont Tannerella forsythia, it is considered a putative health-associated bacterium. In this paper, we identified that this organism could be grown in pure culture if N-acetyl muramic acid (NAM) was provided in the media, although surprisingly the genetic basis of this phenomenon is not likely to be due to a lack of NAM synthesis genes. During further microbiological investigations, we showed for the first time that T. HOT-286 possesses a prominent extracellular S-layer with a novel morphology putatively made up of two proteins modified with an unknown glycan. These data further our knowledge of this poorly understood organism and genus that is an important part of the oral and human microbiome.

A cross-sectional study on the periodontal status and prevalence of red complex periodontal pathogens in a Japanese population.

This large-scale study cross-sectionally examined the periodontal status and prevalence of "red complex" bacteria (Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia) in Japanese adults. A total of 977 participants were enrolled in the study. Probing depth (PD), bleeding on probing (BOP), and bone crest level (BCL) were recorded, and the presence of red complex bacteria in the saliva was examined using polymerase chain reaction. The mean BCL value and the percentage of sites with a PD ≥4 mm or the presence of BOP were significantly higher in older participants. The detection rates of P. gingivalis, T. denticola, and T. forsythia were 46.3%, 76.4%, and 61.1%, respectively. The P. gingivalis detection rate significantly increased with age, while those of T. denticola and T. forsythia were comparably high for all age groups. A close correlation between P. gingivalis and the percentage of sites with PD ≥4 mm was indicated by nonlinear canonical correlation analysis. Current smokers exhibited a more advanced disease condition and a significantly higher P. gingivalis detection rate than non-smokers. In conclusion, periodontal condition worsens with age, and P. gingivalis appears to be the red complex bacterium most closely associated with periodontitis.

The Efficacy of an Anatase-Coated Collar Surface in Inhibiting the Bacterial Colonization of Oral Implants: A Pilot Prospective Study in Humans.

PURPOSE: The primary prevention of peri-implantitis onset is a key factor in long-term implant success, and the evaluation of the antibacterial efficacy of different implant surfaces is fundamental in this way. The aim of this study was to assess if implants with collars coated with anatase were less subjected to bacterial colonization than implants with noncoated collars, and to investigate how implant bacterial colonization varies over time. MATERIALS AND METHODS: Eighteen patients in need of implant-supported rehabilitation were selected to have two adjacent implants placed, one with an anatase-coated collar and one with the collar uncoated. Biofilm samples were collected at four sites around each implant at four different time points. Samples were analyzed through polymerase chain reaction (PCR) to detect and calculate the colonization rate of Aggregactibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Prevotella intermedia. RESULTS: Due to one patient dropout and two nonosseointegrated implants, 32 out of 36 placed implants were followed up for 12 months, and 128 samples for each time point were collected: in total, 512 biofilm samples were analyzed. The type and rate of bacterial colonization were not significantly different between the two groups at all the intervals. However, the anatase-coated collar showed no proliferation of T forsythia. A significant difference in marginal bone level could be observed at the 12-month follow-up only. No significant difference in the other clinical and radiographic indexes was observed. CONCLUSION: In this study, anatase-coated collar implants did not seem to provide significantly different microbiologic outcomes than uncoated collar implants. However, the absence of colonization of the species T forsythia and the slightly smaller peri-implant bone loss at the 12-month follow-up suggest that further investigations on anatase coating are needed. Nevertheless, data on bacterial colonization and crestal bone levels need further investigations to draw meaningful conclusions, due to the statistical power of this pilot study.

Microbiological and clinical effects of probiotics and antibiotics on nonsurgical treatment of chronic periodontitis: a randomized placebo- controlled trial with 9-month follow-up.

The aim of this double-blind, placebo-controlled and parallel- arm randomized clinical trial was to evaluate the effects of Lactobacillus rhamnosus SP1-containing probiotic sachet and azithromycin tablets as an adjunct to nonsurgical therapy in clinical parameters and in presence and levels of Tannerella forsythia, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. Forty-seven systemically healthy volunteers with chronic periodontitis were recruited and monitored clinically and microbiologically at baseline for 3, 6 and 9 months after therapy. Subgingival plaque samples were collected from four periodontal sites with clinical attachment level ≥1 mm, probing pocket depth ≥4 mm and bleeding on probing, one site in each quadrant. Samples were cultivated and processed using the PCR technique. Patients received nonsurgical therapy including scaling and root planing (SRP) and were randomly assigned to a probiotic (n=16), antibiotic (n = 16) or placebo (n = 15) group. L. rhamnosus SP1 was taken once a day for 3 months. Azithromycin 500mg was taken once a day for 5 days. All groups showed improvements in clinical and microbiological parameters at all time points evaluated. Probiotic and antibiotic groups showed greater reductions in cultivable microbiota compared with baseline. The placebo group showed greater reduction in number of subjects with P. gingivalis compared with baseline. However, there were no significant differences between groups. The adjunctive use of L. rhamnosus SP1 sachets and azithromycin during initial therapy resulted in similar clinical and microbiological improvements compared with the placebo group.

Association between specific periodontal pathogens, Toll-like receptor-4, and nuclear factor-κB expression in placental tissues of pre-eclamptic women with periodontitis.

AIM: The aim of the present study was to determine the association between the presence of specific periodontal pathogens, Toll-like receptor-4 (TLR-4), and nuclear factor-κB (NF-κB) expression in the placental tissues of pre-eclamptic women. METHODS: Antenatal periodontal screening was performed in 25 normotensive pregnant women and 25 pre-eclamptic women. Subgingival plaque and placental tissue samples were collected from both groups and screened for the presence of Porphyromonas gingivalis (P. gingivalis), Tannerella forsythia, Aggregatibacter actinomycetemcomitans, and Prevotella intermedia (P. intermedia) using real-time polymerase chain reaction. The placental samples were also analyzed to quantify TLR-4 and NF-κB expression. RESULTS: The subgingival plaque samples of pre-eclamptic women showed significantly higher frequencies of P. intermedia. In the placental samples, P. gingivalis, P. intermedia, and the expression of TLR-4 and NF-κB were found to be at significantly higher levels compared to normotensive pregnant women. Using linear regression analysis, the expression of TLR-4 was significantly influenced by the presence of P. gingivalis (coefficient=3.176, 95% confidence interval [CI]: 367-5.986) and P. intermedia (coefficient=2.886, 95% CI: 0.77-5.696), whereas NF-κB expression was influenced only by the presence of P. intermedia (coefficient=2.220, 95% CI: 0.051-4.388) in the placental tissues of pre-eclamptic women. CONCLUSION: An association exists between P. gingivalis and P. intermedia with increased TLR-4 and NF-κB expression in the placenta of pre-eclamptic women with periodontitis.