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Background: DNA methylation of certain genes frequently occurs in neoplastic cells. Although the cause remains unknown, many genes have been identified with such atypical methylation in neoplastic cells. The hypermethylation of E-Cadherin and Cyclooxygenase 2 (COX-2) in chronic inflammation such as chronic periodontitis may demonstrate mild lesion/mutation epigenetic level. This study compares the hypermethylation status of E-Cadherin and COX-2 genes which are often found in breast cancer patients with that in chronic periodontitis.Methods: Total DNA was extracted from the blood samples of 108 systemically healthy non-periodontitis subjects, and the gingival tissues and blood samples of 110 chronic periodontitis patient as well as neoplastic tissues of 106 breast cancer patients. Methylation-specific PCR for E-Cadherin and COX-2 was performed on these samples and the PCR products were analyzed on 2% agarose gel.Results: Hypermethylation of E-Cadherin and COX-2 was observed in 38% and 35% of the breast cancer samples, respectively. In chronic periodontitis patients the detection rate was 25% and 19% respectively, and none was found in the systemically healthy non-periodontitis control subjects. The hypermethylation status was shown to be correlated among the three groups with statistical significance (p < 0.0001). The methylation of CpG islands in E-Cadherin and COX-2 genes in periodontitis patients occurs more frequently in periodontitis patients than in the control subjects, but occurs less frequently than in the breast cancer patients.Conclusions: This set of data shows that the epigenetic change in E-Cadherin and Cyclooxygenase-2 is associated with chronic periodontitis. The epigenetic changes presented in chronic inflammation patients might demonstrate an irreversible destruction in the tissues or organs similar to the effects of cancer. Chronic periodontitis to some extent might be associated with DNA hypermethylation which is related to cancer risk factors. © 2010 Loo et al; licensee BioMed Central Ltd., published_or_final_version

The purpose of this case-control study is to investigate the periodontal conditions in elderly men with and without osteoporosis or osteopenia and to determine their possible association with periodontal destruction.A total of 200 community-dwelling Chinese males (age range: 69 to 78 years; mean ± SD age: 71.9 ± 3.3 years) were recruited from the Jockey Club Center for Osteoporosis Care and Control, The Chinese University of Hong Kong, including 67 subjects with osteoporosis, 66 subjects with osteopenia, and 67 age-matched normal control subjects based on bone mineral density at the hip, spine, and whole body measured by dual-energy x-ray densitometry. All subjects were interviewed using questionnaires and received a full-mouth periodontal examination.Subjects with osteoporosis exhibited a significantly higher percentage of sites with clinical attachment loss (AL)or= 6 mm compared to subjects with osteopenia (P0.05); subjects with osteoporosis also showed a greater percentage of sites with interproximal gingival recession (GR)or = 5 mm than did control subjects (P0.05) after excluding smokers. Subjects with osteoporosis were more likely (odds ratio = 3.3; P0.05) to exhibit interproximal GRor = 5 mm than were control subjects. Osteoporosis remained significantly associated with severe clinical AL and interproximal GR after adjusting for age, supragingival plaque, and number of teeth lost.This study suggests that osteoporosis is associated with severe clinical AL and interproximal GR in elderly Chinese men.

Candida glabrata is a fungal pathogen that causes a variety of mucosal and systemic infections among compromised patient populations with higher mortality rates. Previous studies have shown that biofilm mode of the growth of the fungus is highly resistant to antifungal agents compared with the free-floating or planktonic mode of growth. Therefore, in the present study, we used 2-D DIGE to evaluate the differential proteomic profiles of C. glabrata under planktonic and biofilm modes of growth. Candida glabrata biofilms were developed on polystyrene surfaces and age-matched planktonic cultures were obtained in parallel. Initially, biofilm architecture, viability, and antifungal susceptibility were evaluated. Differentially expressed proteins more than 1.5-fold in DIGE analysis were subjected to MS/MS. The transcriptomic regulation of these biomarkers was evaluated by quantitative real-time PCR. Candida glabrata biofilms were highly resistant to the antifungals and biocides compared with the planktonic mode of growth. Candida glabrata biofilm proteome when compared with its planktonic proteome showed upregulation of stress response proteins, while glycolysis enzymes were downregulated. Similar trend could be observed at transcriptomic level. In conclusion, C. glabrata biofilms possess higher amount of stress response proteins, which may potentially contribute to the higher antifungal resistance seen in C. glabrata biofilms.

CFTR (cystic fibrosis transmembrane conductance regulator) is a cAMP-activated chloride channel that regulates electrolyte and water transport. The present study investigated the expression and localization of CFTR in human gingiva and explored the possible association of CFTR with periodontal conditions. CFTR expression in gingival biopsies from five periodontally healthy subjects and ten subjects with chronic periodontitis and in the RHGE (reconstituted human gingival epithelia) was detected by immunohistochemistry, whereas its expression in gingival biopsies was analysed by immunofluorescence staining. CFTR mRNA was analysed by reverse transcription-PCR. CFTR mRNA was detected in human gingival epithelia and RHGE. CFTR protein was detected in gingival biopsies from both healthy subjects and individuals with periodontitis and in RHGE. In healthy subjects, CFTR expression was mainly confined to the granular and spinous layers of epithelia and localized on the cell membrane. In patients with periodontitis, CFTR was detected in all layers of epithelia and the underlying connective tissues. The mean CFTR expression levels in periodontitis patients were significantly higher than those in healthy subjects. The present study for the first time showed the expression and localization of CFTR in human gingival epithelia. Elevated CFTR expression in periodontitis subjects implies the possible involvement of CFTR in periodontal disease pathogenesis. Further study is warranted to confirm the present findings.

Background: Elucidation of the communal behavior of microbes in mixed species biofilms may have a major impact on understanding infectious diseases and for the therapeutics. Although, the structure and the properties of monospecies biofilms and their role in disease have been extensively studied during the last decade, the interactions within mixed biofilms consisting of bacteria and fungi such as Candida spp. have not been illustrated in depth. Hence, the aim of this study was to evaluate the interspecies interactions of Pseudomonas aeruginosa and six different species of Candida comprising C. albicans, C. glabrata, C. krusei, C. tropicalis, C. parapsilosis, and C. dubliniensis in dual species biofilm development. Results: A significant reduction in colony forming units (CFU) of C. parapsilosis (90 min), C. albicans and C. tropicalis (90 min, 24h and 48h), C. dubliniensis and C. glabrata, (24h and 48h) was noted when co-cultured with P. aeruginosa in comparison to their monospecies counterparts (P, published_or_final_version

Porphyromonas gingivalis lipopolysaccharide (LPS) is a crucial virulence factor strongly involved in the development of chronic periodontitis. It displays a significant amount of lipid A structural heterogeneity, containing both tetra- (LPS1435/1449) and penta-acylated (LPS1690) lipid A structures with opposing effects on E-selectin expression in human endothelial cells. Little is known about how these two isoforms of P. gingivalis LPS could differentially affect host innate immune responses in human gingival epithelia. The present study compares the modulatory effects of P. gingivalis LPS1435/1449and LPS1690on the expression of human β-defensins (hBDs) in the reconstituted human gingival epithelium, and examines the involvements of a panel of pattern recognition receptors in the modulatory effects concerned. It is shown that hBD-1, hBD-2 and hBD-3 mRNAs are significantly up-regulated by P. gingivalis LPS1690, but down-regulated by P. gingivalis LPS1435/1449. Toll-like receptor (TLR) 2 and CD14 mRNAs are also differentially regulated, and the modulation of hBD-2 expression may be through the co-operation of both TLR2 and TLR4. This study suggests that P. gingivalis LPS with different lipid A structures could differentially modulate host innate immune responses in human gingival epithelia, which may be a hitherto undescribed novel pathogenic mechanism of P. gingivalis in periodontal pathogenesis.

Demystification of microbial behaviour in mixed biofilms could have a major impact on our understanding of infectious diseases. The objectives of this study were to evaluatein vitrothe interactions of six differentCandidaspecies and a Gram-negative coliform,Escherichia coli, in dual-species biofilms, and to assess the effect ofE. coliLPS onCandidabiofilm formation. A single isolate ofE. coliATCC 25922 and six different species ofCandida,Candida albicansATCC 90028,Candida glabrataATCC 90030,Candida kruseiATCC 6258,Candida tropicalisATCC 13803,Candida parapsilosisATCC 22019 andCandida dubliniensisMYA-646, were studied using a standard biofilm assay. EachCandidaspecies was co-cultured withE. colion a polystyrene surface and biofilm formation was quantified by a c.f.u. assay. The biofilm was then analysed by Live/Dead staining and fluorescence microscopy (confocal laser-scanning microscopy, CLSM), whilst scanning electron microscopy (SEM) was employed to visualize the biofilm architecture. The effect ofE. coliLPS onCandidabiofilm cell activity at defined time intervals was assessed with an XTT reduction assay. A significant quantitative reduction in c.f.u. counts ofC. tropicalis(after 90 min),C. parapsilosis(after 90 min and 24 h),C. krusei(after 24 h) andC. dubliniensis(after 24 and 48 h) was noted on incubation withE. coliin comparison with their monospecies biofilm counterparts (PE. colicell numbers occurred on co-culture withC. albicans(after 90 min), and an elevation ofE. colicell numbers followed co-culture withC. tropicalis(after 24 h) andC. dubliniensis(after 24 h and 48 h) (PE. coliLPS-treatedC. tropicalisandC. parapsilosisbiofilms (after 48 h), whilst this had the opposite effect forC. dubliniensis(after 24 h) (PE. coliandCandidaspecies in a mixed-species environment mutually modulate biofilm development, both quantitatively and qualitatively, and thatE. coliLPS appears to be a key component in mediating these outcomes.

Aim: Periodontal pathogenesis is characterized by Gram-negative bacteria activation of series of pro- and anti-inflammatory cytokines from host cells through the pathway of lipopolysaccharide (LPS), LPS-binding protein (LBP) and CD14. The present study investigated the expression profiles of interleukin (IL)-1β and IL-10 in periodontal health and disease, and examined the effects of Escherichia coli LPS and LBP interaction on the expression of IL-1β and IL-10 by human gingival fibroblasts (HGF). Material and Methods: Gingival biopsies were collected from 44 subjects with chronic periodontitis and 15 periodontally healthy subjects. The expression of IL-1β and IL-10 was detected by immunohistochemistry. The mRNA expression of IL-1β and IL-10 in HGF was detected by RT-PCR with or without recombinant human LBP (rhLBP), while the peptides were analysed by an enzyme-linked immunosorbent assay. Results: IL-1β was detected in both oral sulcular epithelia of healthy controls and periodontal pocket epithelia of patients. IL-10 was mainly expressed in the intercellular spaces of connective tissues. IL-1β displayed a reverse pattern of expression levels with reference to IL-10, and a negative correlation existed between LBP and the ratio of IL-1β/IL-10. rhLBP suppressed E. coli LPS-induced IL-1β expression by HGF. Conclusion: An appropriate interplay of LBP and cytokines may have a beneficial effect on innate host defence, thereby contributing to periodontal homeostasis.

The human fungal pathogen Candida is able to form biofilms in almost all the medical devices in current use. Indeed, biofilm formation is a major virulence attribute of microorganisms and account for a majority of human infections. Therefore, understanding processes appertaining to biofilm development is an important prerequisite for devising new strategies to prevent or eradicate biofilm-related infections. In the present study we used an array of both conventional and novel analytical tools to obtain a comprehensive view of Candida biofilm development. Enumeration of colony forming units, colorimetric (XTT) assay, Scanning Electron Microscopy (SEM) and novel Confocal Laser Scanning Microscopy (CLSM) coupled with COMSTAT software analyses were utilised to evaluate growth kinetics; architecture and viability of biofilms of a reference (ATCC) and a clinical strain each of two Candida species, C. albicans and C. glabrata. Biofilm growth kinetics on a polystyrene substrate was evaluated from the initial adhesion step (1.5 h) up to 72 h. These analyses revealed substantial inter- and intra-species differences in temporal organisation of Candida biofilm architecture, spatiality and cellular viability, while reaching maturity within a period of 48 h, on a polystyrene substrate. There were substantial differences in the growth kinetics upon methodology, although general trend seemed to be the same. Detailed architectural analysis provided by COMSTAT software corroborated the SEM and CSLM views. These analyses may provide a strong foundation for down stream molecular work of fungal biofilms.

Candida species are the most important fungal pathogens in humans and cause a variety of superficial and systemic diseases. Biofilm formation is a major virulence attribute contributing to Candida pathogenicity. Although the concentration and distribution of nutrients as well as antifungals across the biofilm thickness play a pivotal role in the development and persistence of Candida biofilms, only limited information is available on the latter aspects of Candida biofilms. Therefore, we attempted to characterize the diffusion coefficient (De) of common dietary sugars such as glucose, galactose, and sucrose in Candida albicans biofilms using horizontal attenuated total reflection-Fourier transform infrared spectroscopy (HATR-FTIR). Artificial Candida biofilms were formed using agarose polymers. De of three sugars tested, glucose, galactose, and sucrose in this artificial Candida biofilm model was found to be 4.08E-06 +/- 3.63E-08, 4.08E-06 +/- 3.70E-08, and 5.38E-06 +/- 4.52E-08 cm(2) s(-1), respectively. We demonstrate here the utility of HATR-FTIR for the determination of diffusion of solutes such as dietary sugars across Candida biofilms.

To study oral health conditions, diabetic medical complications and their association in type 2 diabetes mellitus (DM).Cross-sectional survey of 364 type 2 DM patients (63.6 +/- 10.1 years, 54% female) and 161 controls (64.1 +/- 10.6 years, 53% female) with or without essential hypertension, predominantly low-income, attending a hospital were recruited. Periodontal disease (Community Periodontal Index [CPI]) and dental status (decayed, missing and filled teeth [DMFT]) were recorded. Fasting plasma glucose and, for DM patients, HbA1C and DM complications were recorded on enrolment and follow up, respectively.Many DM subjects had fair diabetic control. Both groups (control/DM) had poor oral health: DMFT = 14.5/16.8, CPI 4 = 36%/50%, (P0.02) while DM subjects had less DT(adjusted) = 2.1/1.4 (P0.01). Of the follow-up DM individuals, 294 (81%) had medical complication(s). Regression analyses showed association between advanced periodontal attachment loss (ALoss) and age, male gender, smoking and DM; MT and DMFT were associated with age, female gender, smoking, DM and hypertension. ALoss and DMFT were not associated with DM complications.The oral health of the surveyed Chinese subjects was poor. Type 2 DM subjects were affected more by ALoss and MT but less DT. Subjects with hypertension had higher odds for MT.

The aim of this study was to biotype and characterize phospholipase, proteinase and haemolytic activities of oral Candida albicans isolates from 210 Chinese patients with type 2 diabetes mellitus (DM) and 210 age- and sex-matched healthy controls. Seventy-six and 50 C. albicans isolates were obtained from type 2 DM patients and controls, respectively, using the oral rinse technique. The isolates were characterized with a biotyping system based on enzyme profiles, carbohydrate assimilation patterns and boric acid resistance of the yeasts, and the isolates were further tested for in vitro phospholipase, proteinase and haemolytic activities. The major biotypes of C. albicans isolates from the type 2 DM and control groups were A1R (42.1 %) and J1R (36.0 %), respectively. Significantly higher proteinase and haemolytic activities were found in the isolates from the type 2 DM group (PPPCandida isolates taken from DM patients.

Objective: To investigate the expression of interleukin-1α (IL-1α), IL-1ra and IL-8 by the oral epithelium challenged by various Candida species. Materials and methods: In vitro candidiasis was induced by C. albicans wild type SC5314, its EFG1, CPH1 and secretory aspartyl proteinase (SAP) mutants and, ATCC isolates of C. albicans, C. tropicalis and C. dubliniensis using a reconstituted human oral epithelium (RHOE) model. IL-1α, IL-1ra and IL-8 levels in culture media were quantified by an enzyme-linked immunosorbent assay at 12, 24 and 48 h. Fungal invasion and IL-1ra expression in RHOE were detected by periodic acid-Schiff staining and immunohistochemistry. Results: Overall, the invasive Candida induced relatively higher levels of IL-1α, IL-1ra and IL-8 in the culture media than the noninvasive isolates. IL-1α and IL-1ra levels induced by Candida with hyphal invasion were significantly higher (P

Porphyromonas gingivalis is an etiologic pathogen of periodontitis that is one of the most common inflammatory diseases. Recently, we found that P. gingivalis LPS activated the transcription factor nuclear factor-kappaB (NF-kappaB) through the IkappaB kinase complex (IKK). NF-kappaB is a transcription factor that controls inflammation and host responses. In this study, we examined the role of IKK/NF-kappaBin P. gingivalis LPS-induced gene expression on a genome-wide basis using a combination of microarray and biochemical approaches. A total of 88 early response genes were found to be induced by P. gingivalis LPS in a human THP.1 monocytic cell lines. Interestingly, the induction of most of these genes was abolished or attenuated under the inactivation of IKK/NF-kappaB. Among those IKK/NF-kappaB-dependent genes, 20 genes were NF-kappaB-inducible genes reported previously, and 59 genes represented putative novel NF-kappaB target genes. Using transcription factor binding analysis, we found that most of these putative NF-kappaB target genes contained one or multiple NF-kappaB-binding sites. Also, some transcription factor-binding motifs were overrepresented in the promoter of both known and putative NF-kappaB-dependent genes, indicating that these genes may be regulated in a similar fashion. Furthermore, we found that several transcription factors associated with metabolic and inflammatory responses, including nuclear receptors, activator of protein-1, and early growth responses, were induced by P. gingivalis LPS through IKK/NF-kappaB, indicating that IKK/NF-kappaB may utilize these transcription factors to mediate secondary responses. Taken together, our results demonstrate that IKK/NF-kappaB signaling plays a dominant role in P. gingivalis LPS-induced early response gene expression, suggesting that IKK/NF-kappaB is a therapeutic target for periodontitis.

Aim: To identify risk indicators associated with tooth loss and periodontitis in treated patients responsible for arranging supportive periodontal care (SPC). Materials and Methods: Ninety-seven Chinese subjects (34–77 years) who showed favourable responses to periodontal therapy provided in a teaching hospital 5–12 years previously were recalled. They were advised to seek regular SPC on discharge. Background information, general health status, smoking, oral hygiene habits, follow-up dental care, tooth loss, and periodontal parameters were investigated. Multiple regression analysis was performed. Results: Two hundred and fifty-six teeth had been lost, 195 because of self-reported periodontal reasons. Up to 26.8% sites were with pockets 6 mm. Positive correlations were found between total/periodontal tooth loss and (i) smoking pack-years, (ii) time spent on oral hygiene, (iii) years since therapy's conclusion, (iv) age, and negative correlations with (v) inter-dental brush use, and (vi) education levels. Tooth loss by arch was correlated with wearing of removable partial denture in that arch. Percentage sites with pockets 6 mm were significantly negatively correlated with percentage sites without bleeding on probing. Conclusions: Smokers, more elderly patients, removable partial denture wearers, and patients with lower education levels or not using inter-dental brushes ought to be targeted for clinic-based SPC.

Background: A single nucleotide polymorphism in the promoter region of −1607 bp of the human matrix metalloproteinase-1 (MMP-1) gene has been found to be associated with an increased risk of various inflammatory diseases and cancer metastasis. Objectives: The present study aimed to examine the distribution of MMP-1 genotypes in a group of Chinese subjects with generalized aggressive periodontitis and a group of periodontally healthy subjects, and to evaluate the possible association of the MMP-1 promoter polymorphism with aggressive periodontitis. Methods: Genomic DNA was obtained from whole blood samples in 40 Chinese subjects with generalized aggressive periodontitis and 52 periodontally healthy subjects as controls. MMP-1 promoter fragment was amplified by polymerase chain reaction, and the polymorphisms were analyzed by restriction endonuclease cleavage. The alleles were detected by polyacrylamide gel electrophoresis and visualized with ethidium bromide. Results: The detection frequency of 2G allele was significantly higher in the subjects with generalized aggressive periodontitis (68.7%) than in the control subjects (49%) (p

Summary Objective: The microflora that develops on minocycline strips, used as an adjunct in non-surgical periodontal therapy was studied. Design and methods: Minocycline (1.4 mg in polycaprolactone vehicle) and control strips were applied into all residual pockets (PD ≥ 5 mm, ≥2 pockets/subject) of patients with chronic periodontitis 1 month after a course of non-surgical periodontal therapy. Strips were inserted and retained for 3 days, changed to new strips for 3 more days and then removed. Strips were recovered from 14 (eight test, six control) of the 34 participants at day 0 (strip inserted, left for 30 s, removed), days 3 and 6, for (i) anaerobic culture, (ii) coliforms culture, using MacConkey agar, (iii) yeast culture, using Sabouraud's dextrose agar. Results: The mean anaerobic cfu/strip (×10 5 ; control/test) were 2/6, 24/2, 11/2 at days 0, 3 and 6, respectively ( P > 0.05). The corresponding mean proportion of Gram-negative rods and fusiforms were 27%/21%, 27%/15% and 55%/8%. The proportions of Gram-negative rods on test strips by day 6 were significantly reduced ( P Streptococcus mitis biovar 1 was found on spent test strips (control versus test; 0% versus 38%, Fisher exact test, P = 0.01). Coliform prevalence at days 0, 3 and 6 on control/test strips were 0/13%, 50%/38% and 50%/13%. Yeasts were occasionally isolated. Conclusions: The findings indicated that the minocycline strips but not the control strip supported a microbial colonisation compatible with periodontal health by day 6.

Background: Human β-defensins (hBDs) are antimicrobial peptides which contribute to host innate immunity by disrupting the membrane integrity of a broad spectrum of microorganisms. Objectives: This study aimed to determine the expression profiles of hBD-1 and -2 peptides in gingiva and to assess the possible relations of these antimicrobial peptides with periodontal health and disease. Methods: Seven periodontally healthy subjects and 22 patients with unresolved chronic periodontitis were recruited and the gingival biopsies collected consisted of healthy tissues from the healthy subjects (HT-C); periodontal pocket tissues (PoT) and inflamed connective tissues (ICT) from the base of pocket, i.e. granulation tissues, as well as clinically healthy tissues (HT-P) from the adjacent clinically healthy sites from the patients. The expression of hBD-1 and -2 peptides was detected by immunohistochemistry and quantitatively analyzed with a computerized image processing system. Results: Both hBD-1 and -2 peptides were detected in all periodontally healthy subjects, while hBD-1 was detected in all patients and hBD-2 was found in most of the patients. Their expression was mainly confined to the granular and spinous layers of gingival epithelium, in which hBD-1 was detected in both intercellular spaces and cytoplasm, whereas hBD-2 was mainly observed in the cytoplasm. HT-C expressed significantly higher levels of hBD-2 than HT-P (p < 0.05). Within the patients, both defensins were up-regulated significantly in PoT as compared with the adjacent HT-P (p < 0.05). Conclusions: The present study showed that hBD-1 and -2 were frequently expressed in the granular and spinous layers of gingival epithelia and their expression may be associated with periodontal health and disease.

The present investigation was designed to determine the individual variation of plaque levels in adults over a period of 3 months. The participants were 20 healthy subjects, 11 men and 9 women, with a mean age of 42.3 +/- 7.3(SD) years. Plaque area was determined with a computerized image analysis system and expressed as percentage of tooth area (P% Index). The scoring procedures were carried out three times (tests 1, 2, and 3) at an interval of 4 weeks. After each test all plaque was removed. All subjects were instructed to maintain their personal oral hygiene habits during the study. The results showed no significant differences for the means of P% Index between tests 1, 2, and 3 in the whole mouth, upper and lower jaws, right and left sides, or each tooth surface. The intraindividual plaque levels for individual tooth surfaces were closely correlated between tests 1, 2 and 3. The intraindividual plaque level was consistent in tests 1, 2, and 3 with standard deviations within subjects ranging from 1.1% to 6.2%. This study suggests that individual plaque levels seem to be consistent on the basis of tooth surface over a certain period of time. Individual plaque control should be more directed towards tooth surfaces with comparably high plaque accumulation within the mouth for significant reduction of the overall plaque levels.

Objectives: This study aimed to evaluate the volume of gingival crevicular fluid (GCF) and granulocyte elastase activity in static GCF (sGCF) and flow GCF (fGCF) from subjects with various periodontal conditions. Methods: Eleven periodontally healthy, 10 gingivitis and 12 periodontitis subjects were recruited and the sites investigated consisted of healthy sites from healthy subjects (HH); healthy (HG) and gingivitis sites (GG) from gingivitis subjects; and healthy (HP), gingivitis (GP) and periodontitis sites (PP) from periodontitis subjects. fGCF samples were collected either 1 min or 5 min following sGCF collection by paper strip technique. GCF volume was determined by Periotron® 6000 and granulocyte elastase activity was assayed with a specific substrate [l-pyroglutamyl-l-prolyl-l-valine-p-nitroanilide(pGluProVal-pNA)]. Results: At baseline, no significant differences existed in clinical and GCF parameters between the two matched sites for subsequent collection of fGCF samples either 1 min or 5 min after sGCF sampling in all subjects. The flow exudate in HG and HP sites quickly replenished to sGCF levels, while a delayed replenishment was found in HH sites, despite the similar sGCF volumes of these sites. The GCF volume and elastase levels in the fGCF at 1 min were higher in GP sites than in GG sites (P

Background Chlorhexidine (CHX) is a widely used antimicrobial agent in dentistry. Herein, we report the synthesis of a novel mesoporous silica nanoparticle-encapsulated pure CHX (Nano-CHX), and its mechanical profile and antimicrobial properties against oral biofilms. Methodology/Principal Findings The release of CHX from the Nano-CHX was characterized by UV/visible absorption spectroscopy. The antimicrobial properties of Nano-CHX were evaluated in both planktonic and biofilm modes of representative oral pathogenic bacteria. The Nano-CHX demonstrated potent antibacterial effects on planktonic bacteria and mono-species biofilms at the concentrations of 50–200 µg/mL against Streptococcus mutans, Streptococcus sobrinus, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans and Enterococccus faecalis. Moreover, Nano-CHX effectively suppressed multi-species biofilms such as S. mutans, F. nucleatum, A. actinomycetemcomitans and Porphyromonas gingivalis up to 72 h. Conclusions/Significance This pioneering study demonstrates the potent antibacterial effects of the Nano-CHX on oral biofilms, and it may be developed as a novel and promising anti-biofilm agent for clinical use.

This study determined soluble CD14 (sCD14) levels in gingival crevicular fluid (GCF) and their potential relationship to periodontal conditions in adult periodontitis.GCF was collected from 15 patients with untreated adult periodontitis. sCD14 levels were determined by ELISA and presented as total amount (ng/site) and concentration (microg/ml). The periodontal examination consisted of plaque index (PI), bleeding index (BI), probing depth (PD), and clinical attachment level (CAL). PD and CAL were measured with an electronic probe.sCD14 was detected in all 15 subjects and was found in 59% (62/105) of the sampled sites. The percentage of sites with sCD14 varied greatly, ranging from 14% to 100%. The mean total amount of sCD14 was 1.71+/-0.40, range 0.03 to 5.41 ng/site; the concentration of sCD14 was 14.04+/-4.15, range 0.16 to 51.74 microg/ml. No significant difference in clinical data was found between the sites with and without detectable levels of sCD14. However, on the basis of the individual profile of sCD14 levels, i.e., those individuals with50% of the sites containing sCD14 and mean levels of sCD145.0 microg/ml, the 15 subjects were divided into a high sCD14 group (9 subjects) and a low sCD14 group (6 subjects). Compared to the high group, the low group showed greater mean PD and a higher percentage of sites with PDor = 5.0 mm (P0.05). Consistent with this, sCD14 concentrations showed a negative correlation with PD (r(s) = -0.636, P = 0.0174).The present study shows that sCD14 levels in GCF varied greatly among subjects with untreated adult periodontitis. Individuals with higher levels of sCD14 in GCF and more sites containing sCD14 had fewer deep pockets. The negative correlation between GCF sCD14 levels and probing depth implies a crucial role of sCD14 in bacterially induced periodontal destruction. The relationship between GCF sCD14 levels and probing depth warrants further investigations.

The aim of this study was to investigate oral yeast colonization and oral yeast strain diversity in irradiated (head and neck), dentate, xerostomic individuals. Subjects were recruited from a nasopharyngeal carcinoma clinic and were segregated into group A (age, n = 25; average age ± standard deviation {SD}, 48 ± 6 years; average postirradiation time ± SD, 5 ± 5 years]) and group B (age, ≥60 years [ n = 8; average age ± SD, 67 ± 4 years; average postirradiation time ± SD, 2 ± 2 years]) and were compared with age- and sex-matched healthy individuals in group C (age, n = 20; average age ± SD, 44 ± 12 years] and group D (age, ≥60 years [ n = 10; average age, 70 ± 3 years]). Selective culture of oral rinse samples was carried out to isolate, quantify, and speciate yeast recovery. All test subjects underwent a 3-month comprehensive oral and preventive care regimen plus topical antifungal therapy, if indicated. A total of 12 subjects from group A and 5 subjects from group B were recalled for reassessment of yeast colonization. Sequential (pre- and posttherapy) Candida isolate pairs from patients were phenotypically (all isolate pairs; biotyping and resistotyping profiles) and genotypically ( Candida albicans isolate pairs only; electrophoretic karyotyping by pulsed-field gel electrophoresis, restriction fragment length polymorphism [RFLP], and randomly amplified polymorphic DNA [RAPD] assays) evaluated. All isolates were Candida species. Irradiated individuals were found to have a significantly increased yeast carriage compared with the controls. The isolation rate of Candida posttherapy remained unchanged. A total of 9 of the 12 subjects in group A and 3 of the 5 subjects in group B harbored the same C. albicans or Candida tropicalis phenotype at recall. Varying degrees of congruence in the molecular profiles were observed when these sequential isolate pairs of C. albicans were analyzed by RFLP and RAPD assays. Variations in the genotype were complementary to those in the phenotypic characteristics for some isolates. In conclusion, irradiation-induced xerostomia seems to favor intraoral colonization of Candida species, particularly C. albicans , which appeared to undergo temporal modifications in clonal profiles both phenotypically and genotypically following hygienic and preventive oral care which included topical antifungal therapy, if indicated. We postulate that the observed ability of Candida species to undergo genetic and phenotypic adaptation could strategically enhance its survival in the human oral cavity, particularly when salivary defenses are impaired.

Relevant papers were identified by using Medline–PubMed and the Cochrane Central Register of Controlled Trials. Papers were assessed for inclusion independently by two reviewers and only those published in the English language were chosen. Randomised controlled clinical trials (RCT) or controlled clinical trials (CCT) conducted in adults with good general health were selected. Evaluation parameters included changes in dental plaque, gingival bleeding/ inflammation and probing pocket depth. Study quality was assessed based upon study design, evaluation period, profiles of subjects, method of randomisation, blindness of examiners and completeness of followup assessment. Data were extracted by three reviewers. As the selected studies showed considerable heterogeneity in the study designs, characteristics, outcome variables and results, a descriptive review of the data was presented instead of performing a meta-analysis. Seven papers (four RCT and three CCT) were included. Mean values and standard deviations were collected from the data. Data showed that oral irrigation does not reduce plaque scores more than toothbrushing or regular oral hygiene measures. This systematic review suggests that oral irrigation as an adjunct to toothbrushing does not have a beneficial effect in reducing dental plaque, but it may improve gingival health.

This study aimed to determine the association between the levels of granulocyte elastase and prostaglandin E2 (PGE2) in GCE and the concomitant presence of periodontopathogens in untreated adult periodontitis (AP). GCF and subgingival plaque were sampled by paper strips and paper points respectively, from various periodontal sites in 16 AP subjects. Granulocyte elastase activity in GCF was analyzed with a low molecular weight substrate specific for granulocyte elastase, pGluProVal-pNA, and the maximal rate of elastase activity (MR-EA, mAbs/min/site) was calculated. PGE2 levels in GCF were determined by radioimmunoassay. 5 species-specific DNA probes were used to detect the presence of A. actinomyceterncomitans (A.a., ATCC 43718), B. forsythus (B.f, ATCC 43037), P. gingivalis (P.g., ATCC 33277), P. intermedia (P.i., ATCC 33563), and T. denticola (T.d., ATCC 35405), with a sensitivity of 10(3) cells/paper point. No A.a. was detectable from all sites sampled. The predominant combination of species detected was B.f., P.g., P.i. & T.d. and it was significantly higher at periodontitis sites (68%) than at healthy (7%) or gingivitis sites (29%) (p

Periodontitis consists of a mixture of diseases, most of which respond favorably to traditional mechanical therapy. It is now recognized that advanced periodontitis does not always respond to conventional management with scaling, periodontal surgery, and oral hygiene measures. However, various types of antibiotics given systemically or locally improve the success rate of periodontal therapy. In short-term studies, it has been shown that metronidazole, when systemically administered after debridement, resulted in treatment benefits including less need for surgical intervention.In this double-blind study, we evaluated periodontal treatment involving initial non-surgical treatment, systemic administration of metronidazole for 1 week, and then follow-ups for scaling and root planing every 6 months, for 5 years. The study population consisted of 64 subjects (37 smokers and 27 non-smokers), mean age 36.3 (+/-3.0 SD) years, with severe periodontal disease. After initial scaling and root planing, patients were randomly assigned to the intervention or placebo groups: 400 mg metronidazole or a placebo administered at 8-hour intervals for 1 week. The participants underwent an extensive clinical periodontal examination. Gingival crevicular fluid (GCF) was analyzed for spirochetes and granulocytes. Samples were cultured for Actinobacillus actinomycetemcomitans (A.a.), Porphyromonas gingivalis (Pg.), and Prevotella intermedia (Pi.).The number of patients infected with A.a., Pg., Pi., and spirochetes decreased during the study. Most patients who harbored spirochetes at the end of the study had these microorganisms at the beginning. Smokers responded less favorably to periodontal therapy than non-smokers. Non-smoking patients who required only non-surgical therapy in the intervention group showed statistically significant improvement in the clinical parameters after 5 years. Patients with complete healing, defined as the absence of inflamed sitesor =5 mm, after 5 years were found only in the intervention group. The patients considered healthy after 5 years were the same patients found to be healthy after 6 months.Decisive factors in the sustained long-term improvement of patients who respond satisfactorily to treatment are probably initial scaling and root planing; a brief course of metronidazole; and regular follow-up examinations at 6-month intervals for oral hygiene and scaling and root planing.

Background Porphyromonas gingivalis lipopolysaccharide (LPS) is a crucial virulence factor strongly associated with chronic periodontitis which is the primary cause of tooth loss in adults. It exhibits remarkable heterogeneity containing tetra-(LPS1435/1449) and penta-(LPS1690) acylated lipid A structures. Human gingival fibroblasts (HGFs) as the main resident cells of human gingiva play a key role in regulating matrix metalloproteinases (MMPs) and contribute to periodontal homeostasis. This study investigated the expression and regulation of MMPs1-3 and tissue inhibitors of MMP-1 (TIMP-1) in HGFs in response to P. gingivalis LPS1435/1449 and LPS1690 and hexa-acylated E. coli LPS as a reference. The expression of MMPs 1–3 and TIMP-1 was evaluated by real-time PCR and ELISA. Results The MMP-3 mRNA and protein were highly upregulated in P. gingivalis LPS1690- and E. coli LPS-treated cells, whereas no induction was observed in P. gingivalis LPS1435/1449-treated cells. On the contrary, the expression of MMP-1 and −2 was not significantly affected by P. gingivalis LPS lipid A heterogeneity. The TIMP-1 mRNA was upregulated in P. gingivalis LPS1435/1449- and E. coli LPS-treated cells. Next, signal transduction pathways involved in P. gingivalis LPS-induced expression of MMP-3 were examined by blocking assays. Blockage of p38 MAPK and ERK significantly inhibited P. gingivalis LPS1690-induced MMP-3 expression in HGFs. Conclusion The present findings suggest that the heterogeneous lipid A structures of P. gingivalis LPS differentially modulate the expression of MMP-3 in HGFs, which may play a role in periodontal pathogenesis.

Granulocyte elastase was determined in the gingival crevicular fluid (GCF) of 18 periodontitis patients. They initially had similar severity of disease but had responded differently to 5-yr maintenance, 13 responders and 5 non-responders. A total of 102 sites were investigated and categorized as: i) consistently healthy, ii) healthy after treatment, iii) gingivitis, and iiii) periodontitis, according to clinical criteria. GCF elastase activity was determined with a granulocyte-specific substrate. The sites from non-responders had consistently higher elastase levels than the corresponding category of sites from responders, despite similar gingival inflammation and periodontal destruction, with the exception of consistently healthy sites. Within the non-responders, the periodontitis sites had higher elastase levels than the gingivitis sites commensurate with probing depth, while no difference existed between gingivitis sites and sites healthy after treatment, despite a difference in probing depth. In contrast, in the responders similar elastase levels were found at the periodontitis sites and gingivitis sites despite difference in probing depth, while both diseased sites had higher elastase levels than the sites healthy after treatment, commensurate with probing depth. This study suggests that increased granulocyte-specific elastase levels in GCF may serve as a diagnostic marker for refractory periodontitis patients.

The purpose was to describe the current periodontal status in a Swedish urban population aged 31-40 yr. 1681 individuals, 840 men and 841 women, participated in the study. 68.5% of the subjects had low amount of plaque, 82.8% low level of calculus and 28.9% healthy gingiva or mild gingivitis. 82.8% of the subjects had no pockets with probing depth (PD) > or = 5 mm. 4.9% of the subjects had one tooth with PD > or = 5 mm, 6.7% 2-5 teeth, 2.4% 6-9 teeth and 3.2% > or = 10 teeth with pockets. 55.8% of the subjects had no missing teeth, third molars excluded. 16.5% had one tooth missing, 23.8% 2-5 teeth, 2.7% 6-9 teeth and 1.2% > or = 10 teeth. 8.6% of the subjects had at least one front tooth missing, 28.7% one premolar and 24.1% one molar missing. Men had significantly higher scores than women for plaque (DI-S), calculus (CI-S), gingivitis (GI-M), and number and percent of remaining teeth with PD > or = 5 mm. Smokers had significantly higher scores than non-smokers for DI-S, CI-S, GI-M, number and percent of remaining teeth with PD > or = 5 mm, and number of missing teeth. The individuals who visited the dentist every year had better oral hygiene and gingival status than those who attended for > 3 yr. The multiple regression analysis showed that calculus (P = 0.0001) smoking (P = 0.001), and dental visits (P = 0.0284) were significantly correlated to the number of teeth with PD > or = 5 mm.

SUMMARY The human gingival niche is a unique microbial habitat. In this habitat, biofilm organisms exist in harmony, attached to either enamel or cemental surfaces of the tooth as well as to the crevicular epithelium, subjacent to a rich vascular plexus underneath. Due to this extraordinary anatomical juxtaposition, plaque biofilm bacteria have a ready portal of ingress into the systemic circulation in both health and disease. Yet the frequency, magnitude, and etiology of bacteremias due to oral origin and the consequent end organ infections are not clear and have not recently been evaluated. In this comprehensive review, we address the available literature on triggering events, incidence, and diversity of odontogenic bacteremias. The nature of the infective agents and end organ infections (other than endocarditis) is also described, with an emphasis on the challenge of establishing the link between odontogenic infections and related systemic, focal infections.