Synergistic antibacterial activity of herbal extracts with antibiotics on bacteria responsible for periodontitis.

INTRODUCTION: Development of bacterial resistance and antimicrobial side-effect has shifted the focus of research toward Ethnopharmacology. A biologically active compound derived from the plants may increase the effectiveness of antibiotic when used in combination. The present study aims to determine the synergistic antibacterial effect of ethanolic extracts of Punica granatum (pericarp), Commiphora molmol, Azadirachta indica (bark) in combination with amoxicillin, metronidazole, tetracycline, and azithromycin on periodontopathic bacteria: Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola and Aggregatibacter actinomycetemcomitans. METHODOLOGY: Periodontopathic bacterial strains were isolated from the plaque sample that was collected from periodontitis patients and grown under favorable conditions. Susceptibility of bacteria to the antibiotics and extracts was determined by disc diffusion method by measuring the diameter of the inhibition zones. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of plant extracts were evaluated against each bacterium. Synergistic effect of plant extract in combination with antibiotics was tested against each bacterium by measuring the diameter of zone of inhibition (ZOI). RESULTS: Findings revealed that all plant extracts exhibited an inhibitory effects on the proliferation and growth of periodontopathic bacteria. The maximum antibacterial effect was exhibited by C. molmol on P. gingivalis (ZOI = 20 ± 0.55 mm, MIC = 0.53 ± 0.24 mg/mL and MBC = 5.21 ± 1.81 mg/mL) (p < 0.05), meanwhile, no antibacterial activity was exhibited by P. granatum on T. forsythia. Synergistic antibacterial effect was recorded when plant extracts were used in combination with antibiotics. The best synergism was exhibited by P. granatum with amoxicillin against A. actinomycetemcomitans (24 ± 1.00 mm) (p < 0.05). CONCLUSIONS: The synergistic test showed significant antibacterial activity when plant extracts were combined with antibiotics against all the experimented bacteria.

Characterization of the O-Glycoproteome of Tannerella forsythia.

Tannerella forsythia is a Gram-negative oral pathogen known to possess an O-glycosylation system responsible for targeting multiple proteins associated with virulence at the three-residue motif (D)(S/T)(A/I/L/V/M/T). Multiple proteins have been identified to be decorated with a decasaccharide glycan composed of a poorly defined core plus a partially characterized species-specific section. To date, glycosylation studies have focused mainly on the two S-layer glycoproteins, TfsA and TfsB, so the true extent of glycosylation within this species has not been fully explored. In the present study, we characterize the glycoproteome of T. forsythia by employing FAIMS-based glycopeptide enrichment of a cell membrane fraction. We demonstrate that at least 13 glycans are utilized within the T. forsythia glycoproteome, varying with respect to the presence of the three terminal sugars and the presence of fucose and digitoxose residues at the reducing end. To improve the localization of glycosylation events and enhance the detection of glycopeptides, we utilized trifluoromethanesulfonic acid treatment to allow the selective chemical cleavage of glycans. Reducing the chemical complexity of glycopeptides dramatically improved the number of glycopeptides identified and our ability to localize glycosylation sites by ETD fragmentation, leading to the identification of 312 putative glycosylation sites in 145 glycoproteins. Glycosylation site analysis revealed that glycosylation occurs on a much broader motif than initially reported, with glycosylation found at (D)(S/T)(A/I/L/V/M/T/S/C/G/F). The prevalence of this broader glycosylation motif in the genome suggests the existence of hundreds of potential O-glycoproteins in this organism. IMPORTANCE Tannerella forsythia is an oral pathogen associated with severe forms of periodontal disease characterized by destruction of the tooth's supporting tissues, including the bone. The bacterium releases a variety of proteins associated with virulence on the surface of outer membrane vesicles. There is evidence that these proteins are modified by glycosylation, and this modification is essential for virulence in producing disease. We have utilized novel techniques coupled with mass spectrometry to identify over 13 glycans and 312 putative glycosylation sites in 145 glycoproteins within T. forsythia. Glycosylation site analysis revealed that this modification occurs on a much broader motif than initially reported such that there is a high prevalence of potential glycoproteins in this organism that may help to explain its role in periodontal disease.

Efficacy of ß-caryophyllene for periodontal disease related factors.

OBJECTIVE: This study aimed to investigate the antimicrobial activity of ß-caryophyllene against periodontopathogens as well as its inhibitory effects on the expression of inflammatory cytokines and production of volatile sulfur compounds by lipopolysaccharide and periodontopathogenic enzymes, respectively. DESIGN: The antimicrobial activity of ß-caryophyllene againstPorphyromonas gingivalis, Tannerella forsythia, and Treponema denticola was investigated via a susceptibility assay using a microplate reader. THP-1 cells were treated with lipopolysaccharide in the presence or the absence of ß-caryophyllene, and the expression and production of inflammatory cytokines were then analyzed by a real-time reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay. After fluorescence-labelling lipopolysaccharide, the effect of ß-caryophyllene on the binding of lipopolysaccharide to the cell wall was investigated via flow cytometry. The spent culture media of P. gingivalis was shaken with or without ß-caryophyllene and gaseous volatile sulfur compounds (VSCs) were measured by a gas chromatograph. RESULTS: ß-caryophyllene showed strong the antimicrobial activity against periodontopathogens. It also reduced lipopolysaccharide-induced expression and production of cytokines, thereby inhibiting the binding of lipopolysaccharide-binding to toll-like receptors by interfering with the complex of lipopolysaccharide and CD14 or lipopolysaccharide-binding protein. ß-caryophyllene also inhibited the emission of gaseous VSCs produced byP. gingivalis. CONCLUSIONS: ß-caryophyllene may improve periodontal health via antimicrobial activity against periodontopathogens, reducing inflammation caused by lipopolysaccharide, and by neutralizing VSCs.

Comparative evaluation of antiplaque and antigingivitis effects of an herbal and chlorine dioxide mouthwashes: A clinicomicrobiological study.

AIM: The aim of the present study was to compare the efficacy of herbal mouthwash and chlorine dioxide mouthwash in reduction of plaque and gingivitis. SETTINGS AND DESIGN: In a randomized clinical trial, forty patients were randomly selected and divided equally into two groups. MATERIALS AND METHODS: After professional oral prophylaxis, the clinical parameters plaque index, gingival index, and modified sulcular bleeding index were recorded at baseline, 7th day, 14th day, and 21st day. The plaque samples were collected from gingival sulcus with an absorbent sterile paper point and were stored in a thioglycollate broth, then sent for microbiological examination. The microbial colony-forming units were assessed at baseline, 7th day, 14th day, and 21st day for Streptococcus mutans, Tannerella forsythia, and Fusobacterium nucleatum. RESULTS: There was a statistical significant reduction in both clinical and microbiological parameters were observed with use of both the mouthwashes. However, herbal mouthwash was more effective in reducing the plaque and gingivitis than chlorine dioxide mouthwash. CONCLUSION: Herbal mouthwash was statistically efficacious in controlling plaque and gingivitis with potent antimicrobial activity.

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.

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

ABSTRACT Objective: 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. Material and Methods: 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. Results: 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. Conclusions: 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.

Inhibition of malodorous gas formation by oral bacteria with cetylpyridinium and zinc chloride.

OBJECTIVE: The antimicrobial efficacy of zinc- (ZnCl2) and cetylpyridinium-chloride (CPC) and their inhibition capacity on volatile sulfur compound (VSC) production by oral bacterial strains were investigated. DESIGN: Minimum inhibitory concentrations (MIC) and growth curves were determined for ZnCl2, CPC, and CPC with ZnCl2 solutions against eight oral microorganisms (Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, Tannerella forsythia, Staphylococcus aureus and Streptococcus mutans) known to be involved in the pathophysiology of both halitosis and periodontal disease. Gas chromatography was applied to measure VSCs (H2S, CH3SH, (CH3)2S) production levels of each strains following exposure to the solutions. RESULTS: ZnCl2 and CPC effectively inhibited growth of all eight strains. ZnCl2 was generally more effective than CPC in suppressing bacterial growth excluding A. actinomycetemcomitans, P. intermedia, and T. forsythia. Synergism between CPC and ZnCl2 was shown in A. actinomycetemcomitans. The MIC for CPC was significantly lower than ZnCl2. VSC production was detected in five bacterial strains (A. actinomycetemcomitans, F. nucleatum, P. gingivalis, T. denticola, and T. forsythia). Each bacterial strain showed unique VSCs production profiles. H2S was produced by F. nucleatum, P. gingivalis, and T. denticola, CH3SH by all five strains and (CH3)2S by A. actinomycetemcomitans, F. nucleatum, P. gingivalis, and T. denticola. Production of CH3SH, the most malodorous component among the three major VSCs from mouth air was evident in F. nucleatum and T. forsythia. CONCLUSION: Both ZnCl2 and CPC effectively inhibit bacterial growth causative of halitosis and periodontal disease, resulting in a direct decrease of bacterial VSCs production.

Microbiologic Response to Periodontal Therapy and Multivariable Prediction of Clinical Outcome.

BACKGROUND: This study assesses the microbiologic effects of a two-phase antimicrobial periodontal therapy and tested microbiologic, clinical, and biologic markers as prognostic indicators for clinical success. METHODS: Eighty patients with chronic or aggressive periodontitis received periodontal treatment supplemented with 375 mg amoxicillin plus 500 mg metronidazole, three times daily for 7 days. In group A, antibiotics were given during the first non-surgical phase (T1); in group B, antibiotics were given during the second surgical phase (T2). Six microorganisms, group assignment, demographic and clinical variables, peak values of 15 cytokines, and nine acute-phase proteins in serum were evaluated as potential predictors of at least one site with probing depth (PD) >4 mm and bleeding on probing (BOP) at 12 months post-therapy. RESULTS: T1 decreased the counts of Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia (Pi), and Treponema denticola significantly more in group A than group B. Aggregatibacter actinomycetemcomitans and Parvimonas micra (Pm) showed a significant decrease only if the treatment was supplemented with antibiotics, i.e., T1 in group A, or T2 in group B. After T2, differences between groups were no longer significant. A multivariable model including four parameters revealed a predictive value of Pm (odds ratio [OR] = 4.38, P = 0.02) and Pi (OR = 3.44, P = 0.049) and yielded moderate accuracy for predicting the treatment outcome (area under the curve = 0.72). Host-derived factors and treatment sequence were not significantly associated with the outcome. CONCLUSIONS: Long-term microbiologic outcomes of periodontal therapy with adjunctive antibiotics either in T1 or T2 were similar. Detection of Pm before therapy was a predictor for persistence of sites with PD >4 mm and BOP at 12 months post-treatment.

New bicyclic brominated furanones as potent autoinducer-2 quorum-sensing inhibitors against bacterial biofilm formation.

Bacterial behaviors such as virulence factor secretion and biofilm formation are critical for survival, and are effectively regulated through quorum sensing, a mechanism of intra- and interspecies communication in response to changes in cell density and species complexity. Many bacterial species colonize host tissues and form a defensive structure called a biofilm, which can be the basis of inflammatory diseases. Periodontitis, a chronic inflammatory disease affecting the periodontium, is caused by subgingival biofilms related to periodontopathogens. In particular, Fusobacterium nucleatum is a major co-aggregation bridge organism in the formation and growth of subgingival biofilms, linking the early and late colonizers in periodontal biofilms. According to our previous study, the intergeneric quorum-sensing signal molecule autoinducer-2 (AI-2) of F. nucleatum plays a key role in intra- and interspecies interactions of periodontopathogens, and may be a good target for periodontal biofilm inhibition. Recently, brominated furanones produced by the macroalga Delisea pulchra were shown to inhibit biofilm formation via AI-2, and have been investigated toward the goal of increasing the inhibition effect. In this study, we describe the synthesis of new bromofuranone analogs, i.e., 3-(dibromomethylene)isobenzofuran-1(3H)-one derivatives, and demonstrate their inhibitory activities against biofilm formation by periodontopathogens, including F. nucleatum, Porphyromonas gingivalis, and Tannerella forsythia.

Influence of a triclosan toothpaste on periodontopathic bacteria and periodontitis progression in cardiovascular patients: a randomized controlled trial.

BACKGROUND AND OBJECTIVE: Triclosan/copolymer toothpaste is effective in controlling plaque and gingivitis and in slowing the progression of periodontitis. This study describes its influence on microbiological and clinical outcomes, over a 5-year period, in patients with established cardiovascular disease (CVD). MATERIAL AND METHODS: Four-hundred and thirty-eight patients were recruited from the Cardiovascular Unit at The Prince Charles Hospital, Brisbane, Australia, and randomized to triclosan or placebo groups. Six sites per tooth were examined annually for probing pocket depth and loss of attachment. These outcomes were analysed, using generalized linear modelling, in 381 patients who had measurements from consecutive examinations. Concurrent load of the periodontal pathogens Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Tannerella forsythia and Porphyromonas gingivalis was determined, using quantitative real-time PCR, in 437 patients with baseline plaque samples. Group comparisons were expressed as geometric means. The chi-square test was used to test for differences between the two groups of patients with regard to the proportion of patients with different numbers of bacterial species. RESULTS: There was no difference in general health or periodontal status between the groups at baseline. There was a significant reduction in the number of interproximal sites showing loss of attachment between examinations, by 21% on average (p < 0.01), in the triclosan group compared with the placebo group. The prevalence of patients with F. nucleatum and A. actinomycetemcomitans was high and remained relatively constant throughout the 5 years of the study. In contrast, the prevalence of T. forsythia and P. gingivalis showed more variability; however, there was no significant difference between the groups, at any time point, in the prevalence of any organism. A significant difference in the geometric means for P. gingivalis (p = 0.01) was seen at years 1 and 4, and for F. nucleatum (p = 0.01) and in the total bacterial load (p = 0.03) at year 2; however, these differences were not statistically significant following a Bonferroni correction for multiple comparisons. There was no difference between the groups in the geometric means for each organism at year 5. CONCLUSION: Within the limitations of the study, these data suggest that the use of triclosan/copolymer toothpaste significantly slowed the progression of periodontitis in patients with CVD but that it had little influence on key subgingival periodontopathic bacteria in these patients over the 5 years of the study.

Effect of Resveratrol on periodontal pathogens during experimental periodontitis in rats.

The objective of this study was to investigate the antibacterial effect of resveratrol against putative periodontal pathogens during the progression of experimental periodontitis in rats. Periodontitis was induced in rats in one of the first molars chosen to receive a ligature. Animals were assigned to one of two groups: daily administration of the placebo solution (control group, n = 12) or 10 mg/Kg of resveratrol (RESV group, n = 12). The therapies were administered systemically for 30 days, for 19 days before periodontitis induction and then for another 11 days. Then, the presence and concentrations of Porphyromonas gingivalis, Tannerella forsythia and Aggregatibacter actinomycetemcomitans in the cotton ligatures collected from the first molars were evaluated using real-time PCR. Inter-group comparisons of the microbiological outcomes revealed that no differences were detected for P. gingivalis, T. forsythia and A. actinomycetemcomitans levels (p > 0.05). Continuous use of resveratrol did not promote additional benefits in microbiological outcomes during experimental periodontitis in rats.

In vitro Resistance Testing of Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia to Triclosan.

AIM: To determine the sensitivity of Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia to triclosan, and determine if these bacteria develop resistance to triclosan upon prolonged exposure. MATERIALS AND METHODS: Susceptibility to triclosan was tested against three periodontal pathogens P. gingivalis, P. intermedia, and T. forsythia. Escherichia coli strains sensitive and resistant to triclosan were used as biological controls to confirm the efficacy of triclosan in the assays. Agar plates were prepared locally with vitamin K and hemin-supplemented medium. RESULTS: Porphyromonas gingivalis and P. intermedia did not grow on plates containing ≥ 2 µg/ml triclosan, while T. forsythia did not grow on ≥ 1.66 µg/ml. Colonies of P. intermedia resistant to triclosan developed after prolonged incubation at 2 µg/ml, but this resistance disappeared during subculture in the absence of triclosan. CONCLUSION: No significant resistance to triclosan was detected for these species. CLINICAL SIGNIFICANCE: Dental products containing triclosan can be beneficial in controlling periodontal disease.

Microbiological and Clinical Effects of Sitafloxacin and Azithromycin in Periodontitis Patients Receiving Supportive Periodontal Therapy.

Sitafloxacin (STFX) is a newly developed quinolone that has robust antimicrobial activity against periodontopathic bacteria. We previously reported that oral administration of STFX during supportive periodontal therapy was as effective as conventional mechanical debridement under local anesthesia microbiologically and clinically for 3 months. The aim of the present study was to examine the short-term and long-term microbiological and clinical effects of systemic STFX and azithromycin (AZM) on active periodontal pockets during supportive periodontal therapy. Fifty-one patients receiving supportive periodontal therapy were randomly allocated to the STFX group (200 mg/day of STFX for 5 days) or the AZM group (500 mg/day of AZM for 3 days). The microbiological and clinical parameters were examined until 12 months after the systemic administration of each drug. The concentration of each drug in periodontal pockets and the antimicrobial susceptibility of clinical isolates were also analyzed. The proportions of red complex bacteria, i.e., Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, which are the representative periodontopathic bacteria, were significantly reduced at 1 month and remained lower at 12 months than those at baseline in both the STFX and AZM groups. Clinical parameters were significantly improved over the 12-month period in both groups. An increase in the MIC of AZM against clinical isolates was observed in the AZM group. These results indicate that monotherapy with systemic STFX and AZM might be an alternative treatment during supportive periodontal therapy in patients for whom invasive mechanical treatment is inappropriate. (This study has been registered with the University Hospital Medical Information Network-Clinical Trials Registry [UMIN-CTR] under registration number UMIN000007834.).

Effect of Resveratrol on periodontal pathogens during experimental periodontitis in rats

Abstract The objective of this study was to investigate the antibacterial effect of resveratrol against putative periodontal pathogens during the progression of experimental periodontitis in rats. Periodontitis was induced in rats in one of the first molars chosen to receive a ligature. Animals were assigned to one of two groups: daily administration of the placebo solution (control group, n = 12) or 10 mg/Kg of resveratrol (RESV group, n = 12). The therapies were administered systemically for 30 days, for 19 days before periodontitis induction and then for another 11 days. Then, the presence and concentrations of Porphyromonas gingivalis, Tannerella forsythia and Aggregatibacter actinomycetemcomitans in the cotton ligatures collected from the first molars were evaluated using real-time PCR. Inter-group comparisons of the microbiological outcomes revealed that no differences were detected for P. gingivalis, T. forsythia and A. actinomycetemcomitans levels (p > 0.05). Continuous use of resveratrol did not promote additional benefits in microbiological outcomes during experimental periodontitis in rats.

Microbiologic Observations After Four Treatment Strategies Among Patients With Periodontitis Maintaining a High Standard of Oral Hygiene: Secondary Analysis of a Randomized Controlled Clinical Trial.

BACKGROUND: The benefit of full-mouth disinfection (FDIS) over traditional scaling and root planing (SRP), with or without adjunctive metronidazole, when treating chronic destructive periodontitis remains equivocal, as does the long-term association between clinical and microbiologic outcomes after such strategies. The aim of this study is to examine the relationship between clinical and microbiologic outcomes of four different treatment strategies for chronic destructive periodontitis among patients who maintain excellent oral hygiene and low gingival bleeding scores. METHODS: One hundred eighty-four patients with periodontitis and capable of maintaining a high standard of oral hygiene were randomly allocated to one of four treatment groups: 1) FDIS + metronidazole; 2) FDIS + placebo; 3) SRP + metronidazole; and 4) SRP + placebo. Recordings of plaque, bleeding on probing, probing depth (PD), and clinical attachment level were carried out in four sites per tooth at baseline, 3 and 12 months after treatment. Before treatment, pooled subgingival samples were obtained from the five deepest pockets, which were sampled again 3 and 12 months after treatment. Microbiologic assessments of eight putative periodontal pathogens were performed using the checkerboard DNA-DNA hybridization method. RESULTS: Levels of bacterial species were already relatively low at baseline. The only microbial factor statistically significantly associated with the clinical outcomes of treatment after 12 months was the association between reductions of Tannerella forsythia and being free from PD ≥5 mm. CONCLUSION: In this clinical trial, the only microbial factor associated with the clinical outcomes after 12 months was a statistically significant association between the reductions of T. forsythia and being free from PD ≥5 mm.

Periodontal Therapy Effects on Nitrite Related to Oral Bacteria: A 6-Month Randomized Clinical Trial.

BACKGROUND: Nitrite is a biologic factor relevant to oral and systemic homeostasis. Through an oral bacteria reduction process, it was suggested that periodontal therapy and chlorhexidine (CHX) rinse could affect nitrite levels, leading to negative effects, such as an increase in blood pressure. This 6-month randomized clinical trial evaluated the effects of periodontal therapeutic protocols on salivary nitrite and its relation to subgingival bacteria. METHODS: One hundred patients with periodontitis were allocated randomly to debridement procedures in four weekly sections (quadrant scaling [QS]) or within 24 hours (full-mouth scaling [FMS]) in conjunction with a 60-day CHX (QS + CHX and FMS + CHX), placebo (QS + placebo and FMS + placebo), or no mouthrinse (QS + none and FMS + none) use. Real-time polymerase chain reaction determined total bacterial, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Streptococcus oralis, and Actinomyces naeslundii levels. Salivary nitrite concentration was determined with Griess reagent. Data were analyzed statistically at baseline and 3 and 6 months by analysis of variance, Kruskal-Wallis, Mann-Whitney U, and Spearman correlation tests (P <0.05). RESULTS: Nitrite concentrations did not tend to change over time. Regarding CHX use, there was a negative correlation between nitrite and total bacterial load at 6 months (FMS + CHX) and one positive correlation between P. gingivalis and nitrite at baseline (QS + CHX). Independently of rinse type, in the FMS group, nitrite correlated negatively with several microbial parameters and also with a higher percentage of deep periodontal pockets. CONCLUSIONS: The relationship between nitrite and bacterial levels appears weak. Short-term scaling exhibited a greater influence on nitrite concentrations then long-term CHX use.

Clinical and microbiological effects of levofloxacin in the treatment of chronic periodontitis: a randomized, placebo-controlled clinical trial.

AIM: The aim of the present study was to evaluate the clinical and microbiological effect of systemic levofloxacin (LFX) as an adjunct to scaling and root planing (SRP) in patients with chronic periodontitis (CP). METHODS: Sixty-five patients with CP were randomly divided into a test (n = 33, SRP and LFX 500 mg, once daily [o.d.]) and a control group (n = 32, SRP and placebo, o.d.). Plaque index (PI), gingival index (GI), percentage of sites with bleeding on probing (%BoP), probing depth (PD), and clinical attachment level (CAL) were recorded at baseline, 10 days, and 1-, 3-, and 6-month intervals. The percentage of sites positive for Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Porphyromonas gingivalis, and Tannerella forsythia were recorded at baseline and at 3 and 6 months. RESULTS: Patients receiving LFX showed statistically-significant improvements in mean PD and CAL. The intergroup difference in PI, GI, and%BoP was not significant at any interval. There was a reduction in the percentage of sites positive for periodontopathic bacteria over the duration of the study in both groups, and a statistically-significant reduction in the number of sites positive for A. actinomycetemcomitans in the LFX group (P < 0.001). CONCLUSION: Levofloxacin was found to significantly improve the clinical and microbiological parameters in CP individuals.