Publications by authors named "Gerard J Linden"

45 Publications

Association between diet and periodontitis: a cross-sectional study of 10,000 NHANES participants.

Am J Clin Nutr 2020 12;112(6):1485-1491

Centre for Public Health, Queen's University Belfast, Belfast, United Kingdom.

Background: Periodontitis is a major cause of tooth loss globally. Risk factors include age, smoking, and diabetes. Intake of specific nutrients has been associated with periodontitis risk but there has been little research into the influence of overall diet, potentially more relevant when formulating dietary recommendations.

Objectives: We aimed to investigate potential associations between diet and periodontitis using novel statistical techniques for dietary pattern analysis.

Methods: Two 24-h dietary recalls and periodontal examination data from the cross-sectional US NHANES, 2009-2014 (n = 10,010), were used. Dietary patterns were extracted using treelet transformation, a data-driven hierarchical clustering and dimension reduction technique. Associations between each pattern [treelet component (TC)] and extent of periodontitis [proportion of sites with clinical attachment loss (CAL) ≥ 3 mm] were estimated using robust logistic quantile regression, adjusting for age, sex, ethnicity, education level, smoking, BMI, and diabetes.

Results: Eight TCs explained 21% of the variation in diet, 1 of which (TC1) was associated with CAL extent. High TC1 scores represented a diet rich in salad, fruit, vegetables, poultry and seafood, and plain water or tea to drink. There was a substantial negative gradient in CAL extent from the lowest to the highest decile of TC1 (median proportion of sites with CAL ≥ 3 mm: decile 1 = 19.1%, decile 10 = 8.1%; OR, decile 10 compared with decile 1: 0.67; 95% CI: 0.46, 0.99).

Conclusions: Most dietary patterns identified were not associated with periodontitis extent. One pattern, however, rich in salad, fruit, and vegetables and with plain water or tea to drink, was associated with lower CAL extent. Treelet transformation may be a useful approach for calculating dietary patterns in nutrition research.
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http://dx.doi.org/10.1093/ajcn/nqaa266DOI Listing
December 2020

Periodontitis and risk of prevalent and incident coronary heart disease events.

J Clin Periodontol 2020 12 9;47(12):1446-1456. Epub 2020 Nov 9.

Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK.

Objective: To investigate periodontitis as a risk factor for prevalent and incident coronary heart disease (CHD) in a group of middle-aged men from Northern Ireland.

Methods: A representative sample of 1400 dentate men had a comprehensive periodontal examination between 2001 and 2003. Prevalent and incident CHD events were validated by independent cardiologists. Logistic regression was used to assess the cross-sectional relationship between periodontitis and prevalent CHD and Cox's proportional hazards analysis to assess the longitudinal relationship between periodontitis and incident CHD.

Results: The mean age of the men at baseline was 63.7 (SD 3.0) years. Of the 1400 men examined, 126 (9%) had prevalent CHD. After adjusting for confounding variables, men with highest mean CAL (Q4) had an odds ratio of 2.15 (95% CI 1.15-4.02), p = 0.02 for prevalent CHD in comparison to men with the lowest CAL (Q1). During a median follow-up of 12.7 years, 137 (10.8%) of the 1274 men free of CHD at baseline had an incident CHD event. After adjusting for confounding variables, the hazard ratio for incident CHD in men in Q4 versus Q1 CAL categories was 1.36 (95% CI 0.81-2.29), p = 0.24.

Conclusions: In this group of dentate men, periodontitis was associated with prevalent CHD. However, there was no association with incident CHD.
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http://dx.doi.org/10.1111/jcpe.13377DOI Listing
December 2020

Natural Antimicrobials in the Dental Pulp.

J Endod 2020 Sep;46(9S):S2-S9

Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland.

Introduction: Like many tissues, the dental pulp is equipped with innate and adaptive immune responses, designed to defend against infection and limit its spread. The pulp's innate immune response includes the synthesis and release of antimicrobial peptides by several dental pulp cell types. These naturally-occurring antimicrobial peptides have broad spectrum activity against bacteria, fungi and viruses. There is a resurgence of interest in the bioactivities of naturally-occurring antimicrobial peptides, largely driven by the need to develop alternatives to antibiotics.

Methods: This narrative review focused on the general properties of antimicrobial peptides, providing an overview of their sources and actions within the dental pulp.

Results: We summarized the relevance of antimicrobial peptides in defending the dental pulp, highlighting the potential for many of these antimicrobials to be modified or mimicked for prospective therapeutic use.

Conclusion: Antimicrobial peptides and novel peptide-based therapeutics are particularly attractive as emerging treatments for polymicrobial infections, such as endodontic infections, because of their broad activity against a range of pathogens.
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http://dx.doi.org/10.1016/j.joen.2020.06.021DOI Listing
September 2020

Chronic periodontitis and reduced respiratory function.

J Clin Periodontol 2019 03 27;46(3):266-275. Epub 2019 Feb 27.

Centre for Public Health, School of Medicine Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK.

Objective: To investigate whether there was an association between chronic periodontitis (CP) and reduced respiratory function.

Methods: A group of dentate 58- to 72-year-old men in Northern Ireland had a comprehensive periodontal examination. Parallel to the periodontal examination, participants completed questionnaires gathering information on their medical history, social circumstances, demographic background and tobacco use. A physical examination assessed anthropometric measures. Fasting blood samples were obtained and analysed for high-sensitivity C-reactive protein (hs-CRP). Spirometry measures were performed using a wedge bellows spirometer (Vitalograph S Model). The primary outcome variable of interest was the percentage predicted forced expiratory volume in one-second (% predicted FEV ). Analysis included multiple linear regression with adjustment for various confounders and a regression-based mediation analysis.

Results: A total of 1,380 men were included in the analysis. The mean age was 63.7 years (SD 3.0). Multiple linear regression analysis showed that a doubling in mean clinical attachment loss (CAL) equated to a -3.33% (95% CI: -4.80, -1.86), p < 0.001 change in % predicted FEV after adjustment for all other potential confounding variables. Systemic inflammation, as measured by hs-CRP, only accounted for a minor mediating pathway effect (9%).

Conclusions: In this homogenous group of dentate men, CP was significantly associated with a reduced respiratory function.
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http://dx.doi.org/10.1111/jcpe.13076DOI Listing
March 2019

Adding smoking to the Fardal model of cost-effectiveness for the lifetime treatment of periodontal diseases.

J Periodontol 2018 11 29;89(11):1283-1289. Epub 2018 Aug 29.

Centre for Public Health, School of Medicine Dentistry and Biomedical Science, Queen's University, Belfast, UK.

Background: Little is known about the financial costs that smoking adds to the lifetime treatment of periodontal disease.

Methods: The total lifetime cost of periodontal treatment was modeled using data from private periodontal practice. The costs of initial and supportive therapy, re-treatment and tooth replacements (with bridgework or implants) were identified using average dental charges from the American Dental Association survey. Smoking costs at $6 and $10 for 20 cigarettes were compared to the costs of lifetime periodontal treatment for stable and unstable compliant patients.

Results: Smoking added 8.8% to the financial cost of the lifetime cost of periodontal therapy in stable maintenance patients, 40.1% in patients who needed one extra maintenance visit, and 71.4% in patients who needed two extra maintenance visits per year in addition to added retreatment. The cost of smoking far exceeded the cost of periodontal treatment; For patients who smoked 10 to 40 cigarettes per day at the cost of $6 or $10 a pack, the cost of smoking exceeded the cost of lifetime periodontal treatment by between 2.7 and 17.9 times. Smoking 40 cigarettes at $10 a packet for 3.4 years would pay for the entire lifetime cost of periodontal treatment.

Conclusion: Smoking adds considerable extra financial costs to the lifetime treatment of periodontal diseases. The cost of smoking itself exceeds the cost of periodontal therapy.
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http://dx.doi.org/10.1002/JPER.17-0467DOI Listing
November 2018

The Naturally Occurring Host Defense Peptide, LL-37, and Its Truncated Mimetics KE-18 and KR-12 Have Selected Biocidal and Antibiofilm Activities Against , , and .

Front Microbiol 2017 31;8:544. Epub 2017 Mar 31.

Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University BelfastBelfast, UK.

Amongst the recognized classes of naturally occurring antimicrobials, human host defense peptides are an important group with an advantage (given their source) that they should be readily translatable to medicinal products. It is also plausible that truncated versions will display some of the biological activities of the parent peptide, with the benefit that they are less costly to synthesize using solid-phase chemistry. The host defense peptide, LL-37, and two truncated mimetics, KE-18 and KR-12, were tested for their inhibitory effects and antibiofilm properties against , , and , microorganisms commonly implicated in biofilm-related infections such as ventilator-associated pneumonia (VAP). Using prediction tools, the truncated peptides KE-18 and KR-12 were selected for minimum inhibitory concentration (MIC) and antibiofilm testing on the basis of their favorable cationicity, hydrophobic ratio, and amphipathicity compared with the parent peptide. Two methods were analyzed for determining peptide efficacy against biofilms; a crystal violet assay and an XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] assay. The biocidal activities (measured by MIC) and antibiofilm activities (measured by a crystal violet assay) appeared to be independent. LL-37 had no biocidal action against (MIC > 250 μg/ml) but significant effects in both biofilm-prevention and biofilm-inhibition assays. KE-18 and KR-12 yielded superior MIC values against all three microorganisms. Only KE-18 had a significant effect in the biofilm-prevention assay, which persisted even at sub-MICs. Neither of the truncated peptides were active in the biofilm-inhibition assay. KE-18 was shown to bind lipopolysaccharide as effectively as LL-37 and to bind lipoteichoic acid more effectively. None of the peptides showed hemolytic activity against human erythrocytes at the concentrations tested. KE-18 should be considered for further development as a natural peptide-derived therapeutic for prevention of multi-species biofilm-related infections such as VAP.
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http://dx.doi.org/10.3389/fmicb.2017.00544DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5374219PMC
March 2017

Periodontitis and Systemic Disease: Association or Causality?

Curr Oral Health Rep 2017 23;4(1):1-7. Epub 2017 Jan 23.

Centre for Public Health, School of Medicine Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK.

Purpose Of Review: The aim was to assess recent evidence that diabetes, metabolic syndrome (MetS) and obesity impact the progression of periodontitis.

Recent Findings: Electronic searches using Embase, Medline, and Web of Science were carried out for epidemiological studies on humans, published between 2014 and 2016. A small number of prospective studies and systematic reviews were identified that in general provide further support for the hypothesis that diabetes, metabolic syndrome and obesity can adversely affect the periodontal condition.

Summary: Confounding remains the most challenging issue in the interpretation of the associations found between diabetes, MetS, obesity and periodontal disease. Recent research applying a Mendelian randomisation approach concluded that the association between obesity and periodontitis is confounded and questioned a role for obesity in causation. Further studies are warranted to assess the issue of causality.
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http://dx.doi.org/10.1007/s40496-017-0121-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5332497PMC
January 2017

Periodontitis and incident type 2 diabetes: a prospective cohort study.

J Clin Periodontol 2017 03 4;44(3):266-274. Epub 2017 Feb 4.

Centre for Public Health, School of Medicine Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK.

Objectives: The aim of this study was to investigate periodontitis as a risk factor for incident type 2 diabetes mellitus (T2DM) in a group of men aged 58-72 years.

Methods: One thousand three hundred and thirty-one dentate, diabetes-free men in Northern Ireland underwent a detailed periodontal examination during 2001-2003. Follow-up was by bi-annual questionnaire and for those reporting diabetes their general medical practitioner was contacted to validate diabetes type, treatment and diagnosis date. Cox's proportional hazard models were used to estimate the effect of periodontitis on incident diabetes. Multivariable analysis included adjustment for various known confounders.

Results: The mean age of the men was 63.7 (SD 3.0) years. There were 80 cases (6.0%) of incident T2DM. Follow-up was for a median period of 7.8 years (IQR 6.7-8.3). After adjusting for confounding variables, the hazard ratio (HR) for incident T2DM in men with moderate/severe periodontitis versus those with no/mild periodontitis was 1.69 (95% CI 1.06-2.69), p = 0.03.

Conclusion: There was evidence in this homogenous group of dentate men, that those with moderate to severe periodontitis had a significantly increased risk of incident T2DM.
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http://dx.doi.org/10.1111/jcpe.12691DOI Listing
March 2017

Increased Population Risk of AIP-Related Acromegaly and Gigantism in Ireland.

Hum Mutat 2017 01 4;38(1):78-85. Epub 2016 Oct 4.

Centre of Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.

The aryl hydrocarbon receptor interacting protein (AIP) founder mutation R304 (or p.R304 ; NM_003977.3:c.910C>T, p.Arg304Ter) identified in Northern Ireland (NI) predisposes to acromegaly/gigantism; its population health impact remains unexplored. We measured R304 carrier frequency in 936 Mid Ulster, 1,000 Greater Belfast (both in NI) and 2,094 Republic of Ireland (ROI) volunteers and in 116 NI or ROI acromegaly/gigantism patients. Carrier frequencies were 0.0064 in Mid Ulster (95%CI = 0.0027-0.013; P = 0.0005 vs. ROI), 0.001 in Greater Belfast (0.00011-0.0047) and zero in ROI (0-0.0014). R304 prevalence was elevated in acromegaly/gigantism patients in NI (11/87, 12.6%, P < 0.05), but not in ROI (2/29, 6.8%) versus non-Irish patients (0-2.41%). Haploblock conservation supported a common ancestor for all the 18 identified Irish pedigrees (81 carriers, 30 affected). Time to most recent common ancestor (tMRCA) was 2550 (1,275-5,000) years. tMRCA-based simulations predicted 432 (90-5,175) current carriers, including 86 affected (18-1,035) for 20% penetrance. In conclusion, R304 is frequent in Mid Ulster, resulting in numerous acromegaly/gigantism cases. tMRCA is consistent with historical/folklore accounts of Irish giants. Forward simulations predict many undetected carriers; geographically targeted population screening improves asymptomatic carrier identification, complementing clinical testing of patients/relatives. We generated disease awareness locally, necessary for early diagnosis and improved outcomes of AIP-related disease.
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http://dx.doi.org/10.1002/humu.23121DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5215436PMC
January 2017

The relationship between adipokines and the onset of type 2 diabetes in middle-aged men: The PRIME study.

Diabetes Res Clin Pract 2016 Oct 28;120:24-30. Epub 2016 Jul 28.

Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Institute of Clinical Science B, Queen's University Belfast, Belfast, BT12 6BJ, United Kingdom; UKCRC Centre of Excellence for Public Health (Northern Ireland), Queen's University Belfast, Belfast, BT12 6BJ, United Kingdom. Electronic address:

Aims: Epidemiological evidence suggests that adipokines may be associated with the onset of type 2 diabetes, but the evidence to date is limited and inconclusive. This study examined the association between adiponectin and leptin and the subsequent diagnosis of type 2 diabetes in a UK population based cohort of non-diabetic middle-aged men.

Methods: Baseline serum levels of leptin and adiponectin were measured in 1839 non-diabetic men aged 50-60years who were participating in the prospective population-based PRIME study. Over a mean follow-up of 14.7years, new cases of type 2 diabetes were determined from self-reported clinical information with subsequent validation by general practitioners.

Results: 151 Participants developed type 2 diabetes during follow-up. In Cox regression models adjusted for age, men in the top third of the leptin distribution were at increased risk (hazard ratio (HR) 4.27, 95% CI 2.67-6.83) and men in the top third of the adiponectin distribution at reduced risk (HR 0.24, 95% CI 0.14-0.42) relative to men in the bottom third. However, significance was lost for leptin after additional adjustment for BMI, waist to hip ratio, lifestyle factors and biological risk factors, including C-reactive protein (CRP). Further adjustment for HOMA-IR also resulted in loss of significance for adiponectin.

Conclusions: This study provides evidence that adipokines are associated with men's future type 2 diabetes risk but not independently of other risk factors.
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http://dx.doi.org/10.1016/j.diabres.2016.07.010DOI Listing
October 2016

Gingival Inflammation and Aggressive Periodontitis in a Child with a Specific Antibody Deficiency.

Dent Update 2016 Mar;43(2):130-2, 135-6

Exuberant gingival inflammation accompanied by periodontitis is a rare finding in a very young child and may indicate a defect in the host response. Affected children should be referred to appropriate specialists to establish a definitive diagnosis. A 5-year-old girl presented with persistent gingival inflammation and periodontal destruction. Immunological investigations identified specific polysaccharide antibody deficiency which, when treated, resulted in a significant improvement in the gingival condition. This case illustrates the need for integrated management by a wide range of dental and medical specialists. Antibody deficiency is rare but, if not identified and treated effectively, can be associated with chronic ill health and decreased life expectancy. CPD/Clinical Relevance: This article describes a rare case of gingival inflammation accompanied by periodontitis in a very young child secondary to an underlying host antibody deficiency and details the investigation, management and clinical outcomes.
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http://dx.doi.org/10.12968/denu.2016.43.2.130DOI Listing
March 2016

Biodentine Reduces Tumor Necrosis Factor Alpha-induced TRPA1 Expression in Odontoblastlike Cells.

J Endod 2016 Apr 11;42(4):589-95. Epub 2016 Feb 11.

Aix Marseille Université, CNRS, Institut des Sciences du Mouvement, Marseille, France.

Introduction: The transient receptor potential (TRP) ion channels have emerged as important cellular sensors in both neuronal and non-neuronal cells, with TRPA1 playing a central role in nociception and neurogenic inflammation. The functionality of TRP channels has been shown to be modulated by inflammatory cytokines. The aim of this study was to investigate the effect of inflammation on odontoblast TRPA1 expression and to determine the effect of Biodentine (Septodent, Paris, France) on inflammatory-induced TRPA1 expression.

Methods: Immunohistochemistry was used to study TRPA1 expression in pulp tissue from healthy and carious human teeth. Pulp cells were differentiated to odontoblastlike cells in the presence of 2 mmol/L beta-glycerophosphate, and these cells were used in quantitative polymerase chain reaction, Western blotting, calcium imaging, and patch clamp studies.

Results: Immunofluorescent staining revealed TRPA1 expression in odontoblast cell bodies and odontoblast processes, which was more intense in carious versus healthy teeth. TRPA1 gene expression was induced in cultured odontoblastlike cells by tumor necrosis factor alpha, and this expression was significantly reduced in the presence of Biodentine. The functionality of the TRPA1 channel was shown by calcium microfluorimetry and patch clamp recording, and our results showed a significant reduction in tumor necrosis factor alpha-induced TRPA1 responses after Biodentine treatment.

Conclusions: In conclusion, this study showed TRPA1 to be modulated by caries-induced inflammation and that Biodentine reduced TRPA1 expression and functional responses.
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http://dx.doi.org/10.1016/j.joen.2015.12.017DOI Listing
April 2016

TNF-α-induced p38MAPK activation regulates TRPA1 and TRPV4 activity in odontoblast-like cells.

Am J Pathol 2015 Nov 8;185(11):2994-3002. Epub 2015 Sep 8.

Centre for Infection and Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom.

The transient receptor potential (TRP) channels are unique cellular sensors that are widely expressed in many neuronal and nonneuronal cells. Among the TRP family members, TRPA1 and TRPV4 are emerging as candidate mechanosensitive channels that play a pivotal role in inflammatory pain and mechanical hyperalgesia. Odontoblasts are nonneuronal cells that possess many of the features of mechanosensitive cells and mediate important defense and sensory functions. However, the effect of inflammation on the activity of the odontoblast's mechanosensitive channels remains unknown. By using immunohistochemistry and calcium microfluorimetry, we showed that odontoblast-like cells express TRPA1 and TRPV4 and that these channels were activated by hypotonicity-induced membrane stretch. Short treatment of odontoblast-like cells with tumor necrosis factor (TNF)-α enhanced TRPA1 and TRPV4 responses to their chemical agonists and membrane stretch. This enhanced channel activity was accompanied by phospho-p38 mitogen-activated protein kinase (MAPK) expression. Treatment of cells with the p38 inhibitor SB202190 reduced TNF-α effects, suggesting modulation of channel activity via p38 MAPK. In addition, TNF-α treatment also resulted in an up-regulation of TRPA1 expression but down-regulation of TRPV4. Unlike TRPV4, enhanced TRPA1 expression was also evident in dental pulp of carious compared with noncarious teeth. SB202190 treatment significantly reduced TNF-α-induced TRPA1 expression, suggesting a role for p38 MAPK signaling in modulating both the transcriptional and non-transcriptional regulation of TRP channels in odontoblasts.
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http://dx.doi.org/10.1016/j.ajpath.2015.07.020DOI Listing
November 2015

The association between subgingival periodontal pathogens and systemic inflammation.

J Clin Periodontol 2015 Sep 1;42(9):799-806. Epub 2015 Oct 1.

Centre for Public Health, School of Medicine Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK.

Aim: To investigate associations between periodontal disease pathogens and levels of systemic inflammation measured by C-reactive protein (CRP).

Methods: A representative sample of dentate 60-70-year-old men in Northern Ireland had a comprehensive periodontal examination. Men taking statins were excluded. Subgingival plaque samples were analysed by quantitative real time PCR to identify the presence of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia. High-sensitivity CRP (mg/l) was measured from fasting blood samples. Multiple linear regression analysis was performed using log-transformed CRP concentration as the dependent variable, with the presence of each periodontal pathogen as predictor variables, with adjustment for various potential confounders.

Results: A total of 518 men (mean age 63.6 SD 3.0 years) were included in the analysis. Multiple regression analysis showed that body mass index (p < 0.001), current smoking (p < 0.01), the detectable presence of P. gingivalis (p < 0.01) and hypertension (p = 0.01), were independently associated with an increased CRP. The detectable presence of P. gingivalis was associated with a 20% (95% confidence interval 4-35%) increase in CRP (mg/l) after adjustment for all other predictor variables.

Conclusion: In these 60-70-year-old dentate men, the presence of P. gingivalis in subgingival plaque was significantly associated with a raised level of C-reactive protein.
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http://dx.doi.org/10.1111/jcpe.12450DOI Listing
September 2015

Replication of the association of GLT6D1 with aggressive periodontitis in a Sudanese population.

J Clin Periodontol 2015 Apr 31;42(4):319-24. Epub 2015 Mar 31.

Faculty of Dentistry, University of Khartoum, Khartoum, Sudan.

Background: Susceptibility to aggressive periodontitis (AgP) is influenced by genetic as well as environmental factors. Studies linking gene variants to AgP have been mainly centred in developed countries with limited data from Africa.

Aim: To investigate whether previously reported candidate gene associations with AgP could be replicated in a population from Sudan.

Methods: The investigation was a case-control design. Cases with AgP (n = 132) and controls (n = 136) were identified from patients attending the Periodontal Department in Khartoum Dental Hospital. Genotyping was performed using the Sequenom MassARRAY iPLEX platform. Analysis focused on gene variants with a minor allele frequency (MAF) > 25% in the Sudanese subjects that had previously been reported to be associated with AgP.

Results: One candidate gene rs1537415 (GLT6D1) was significantly associated with AgP, OR = 1.50 (95% CI 1.04-2.17), p = 0.0295 (increasing to p = 0.09 after correction for multiple testing). The association strengthened to OR = 1.56 (95% CI 1.15-2.16), p = 0.0042 when the controls were supplemented with data from the Hap map for the Yoruba in Ibadan (n = 147) and remained significant (p = 0.013) after correction for multiple testing.

Conclusion: The study independently replicated the finding that rs1537415, a variant in glycosyl transferase gene GLT6D1, is associated with AgP and provided the first report of genetic associations with AgP in a Sudanese population.
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http://dx.doi.org/10.1111/jcpe.12375DOI Listing
April 2015

Antimicrobial and immunomodulatory properties of PGLa-AM1, CPF-AM1, and magainin-AM1: potent activity against oral pathogens.

Regul Pept 2014 Nov 13;194-195:63-8. Epub 2014 Nov 13.

Centre for Infection & Immunity, School of Medicine, Dentistry and Biomedical Sciences, Queen's University, Belfast, Northern Ireland, UK. Electronic address:

Cationic amphipathic α-helical peptides are intensively studied classes of host defence peptides (HDPs). Three peptides, peptide glycine-leucine-amide (PGLa-AM1), caerulein-precursor fragment (CPF-AM1) and magainin-AM1, originally isolated from norepinephrine-stimulated skin secretions of the African volcano frog Xenopus amieti (Pipidae), were studied for their antimicrobial and immunomodulatory activities against oral and respiratory pathogens. Minimal effective concentrations (MECs), determined by radial diffusion assay, were generally lower than minimal inhibitory concentrations (MICs) determined by microbroth dilution. PGLa-AM1 and CPF-AM1 were particularly active against Streptococcus mutans and all three peptides were effective against Fusobacterium nucleatum, whereas Enterococcus faecalis and Candida albicans proved to be relatively resistant micro-organisms. A type strain of Pseudomonas aeruginosa was shown to be more susceptible than the clinical isolate studied. PGLa-AM1 displayed the greatest propensity to bind lipopolysaccharide (LPS) from Escherichia coli, P. aeruginosa and Porphyromonas gingivalis. All three peptides showed less binding to P. gingivalis LPS than to LPS from the other species studied. Oral fibroblast viability was unaffected by 50 μM peptide treatments. Production of the pro-inflammatory cytokine IL-8 by oral fibroblasts was significantly increased following treatment with 1 or 10 μM magainin-AM1 but not following treatment with PGLa-AM1 or CPF-AM1. In conclusion, as well as possessing potent antimicrobial actions, the X. amieti peptides bound to LPS from three human pathogens and had no effect on oral fibroblast viability. CPF-AM1 and PGLa-AM1 show promise as templates for the design of novel analogues for the treatment of oral and dental diseases associated with bacteria or fungi.
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http://dx.doi.org/10.1016/j.regpep.2014.11.002DOI Listing
November 2014

Incorporating severity and risk as factors to the Fardal cost-effectiveness model to create a cost-benefit model for periodontal treatment.

J Periodontol 2014 Mar 21;85(3):e31-9. Epub 2013 Oct 21.

Private practice, State College, PA.

Background: A previously described economic model was based on average values for patients diagnosed with chronic periodontitis (CP). However, tooth loss varies among treated patients and factors for tooth loss include CP severity and risk. The model was refined to incorporate CP severity and risk to determine the cost of treating a specific level of CP severity and risk that is associated with the benefit of tooth preservation.

Methods: A population that received and another that did not receive periodontal treatment were used to determine treatment costs and tooth loss. The number of teeth preserved was the difference of the number of teeth lost between the two populations. The cost of periodontal treatment was divided by the number of teeth preserved for combinations of CP severity and risk.

Results: The cost of periodontal treatment divided by the number of teeth preserved ranged from (US) $1,405 to $4,895 for high or moderate risk combined with any severity of CP and was more than $8,639 for low risk combined with mild CP. The cost of a three-unit bridge was $3,416, and the cost of a single-tooth replacement was $4,787.

Conclusion: Periodontal treatment could be justified on the sole basis of tooth preservation when CP risk is moderate or high regardless of disease severity.
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http://dx.doi.org/10.1902/jop.2013.130237DOI Listing
March 2014

Periodontal systemic associations: review of the evidence.

J Periodontol 2013 Apr;84(4 Suppl):S8-S19

Centre for Public Health, School of Medicine Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland, UK.

Aim: To critically appraise recent research into associations between periodontal disease and systemic diseases and conditions specifically respiratory disease, chronic kidney disease, rheumatoid arthritis, cognitive impairment, obesity, metabolic syndrome and cancer.

Methods: A MEDLINE literature search of papers published between 2002 and April 2012 was conducted. Studies that included periodontitis as an exposure were identified. Cross-sectional epidemiological investigations on large samples, prospective studies and systematic reviews formed the basis of the narrative review. A threshold set for the identification of periodontitis was used to identify those studies that contributed to the conclusions of the review.

Results: Many of the investigations were cross-sectional secondary analyses of existing data sets in particular the NHANES studies. There were a small number of systematic reviews and prospective studies. There was substantial variability in the definitions of exposure to periodontitis. A small number of studies met the threshold set for periodontitis and supported associations; however, in some of the chronic diseases there were no such studies. There was strong evidence from randomized controlled trials that interventions, which improve oral hygiene have positive effects on the prevention of nosocomial pneumonias.

Conclusions: There was substantial heterogeneity in the definitions used to identify periodontitis and very few studies met a stringent threshold for periodontitis. Published evidence supports modest associations between periodontitis and some, although not all, of the diseases and conditions reviewed. There is a need to reach a consensus on what constitutes periodontitis for future studies of putative associations with systemic diseases.
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http://dx.doi.org/10.1902/jop.2013.1340010DOI Listing
April 2013

Periodontal systemic associations: review of the evidence.

J Clin Periodontol 2013 Apr;40 Suppl 14:S8-19

Centre for Public Health, School of Medicine Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland, UK.

Aim: To critically appraise recent research into associations between periodontal disease and systemic diseases and conditions specifically respiratory disease, chronic kidney disease, rheumatoid arthritis, cognitive impairment, obesity, metabolic syndrome and cancer.

Methods: A MEDLINE literature search of papers published between 2002 and April 2012 was conducted. Studies that included periodontitis as an exposure were identified. Cross-sectional epidemiological investigations on large samples, prospective studies and systematic reviews formed the basis of the narrative review. A threshold set for the identification of periodontitis was used to identify those studies that contributed to the conclusions of the review.

Results: Many of the investigations were cross-sectional secondary analyses of existing data sets in particular the NHANES studies. There were a small number of systematic reviews and prospective studies. There was substantial variability in the definitions of exposure to periodontitis. A small number of studies met the threshold set for periodontitis and supported associations; however, in some of the chronic diseases there were no such studies. There was strong evidence from randomized controlled trials that interventions, which improve oral hygiene have positive effects on the prevention of nosocomial pneumonias.

Conclusions: There was substantial heterogeneity in the definitions used to identify periodontitis and very few studies met a stringent threshold for periodontitis. Published evidence supports modest associations between periodontitis and some, although not all, of the diseases and conditions reviewed. There is a need to reach a consensus on what constitutes periodontitis for future studies of putative associations with systemic diseases.
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http://dx.doi.org/10.1111/jcpe.12064DOI Listing
April 2013

All-cause mortality and periodontitis in 60-70-year-old men: a prospective cohort study.

J Clin Periodontol 2012 Oct 27;39(10):940-6. Epub 2012 Jul 27.

Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland, UK.

Objective: To investigate the association between periodontitis and mortality from all causes in a prospective study in a homogenous group of 60- to 70-year-old West European men.

Methodology: A representative sample of 1400 dentate men, (mean age 63.8, SD 3.0 years), drawn from the population of Northern Ireland, had a comprehensive periodontal examination between 2001 and 2003. Men were divided into thirds on the basis of their mean periodontal attachment loss (PAL). The primary endpoint, death from any cause, was analysed using Kaplan-Meier survival plots and Cox's proportional hazards model.

Results: In total, 152 (10.9%) of the men died during a mean follow-up of 8.9 (SD 0.7) years; 37 (7.9%) men in the third with the lowest PAL (<1.8 mm) died compared with 73 (15.7%) in the third with the highest PAL (>2.6 mm). The unadjusted hazard ratio (HR) for death in the men with the highest level of PAL compared with those with the lowest PAL was 2.11 (95% CI 1.42-3.14), p < 0.0001. After adjustment for confounding variables (age, smoking, hypertension, BMI, diabetes, cholesterol, education, marital status and previous history of a cardiovascular event) the HR was 1.57 (1.04-2.36), p = 0.03.

Conclusion: The European men in this prospective cohort study with the most severe loss of periodontal attachment were at an increased risk of death compared with those with the lowest loss of periodontal attachment.
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http://dx.doi.org/10.1111/j.1600-051X.2012.01923.xDOI Listing
October 2012

The lifetime direct cost of periodontal treatment: a case study from a Norwegian specialist practice.

J Periodontol 2012 Dec 13;83(12):1455-62. Epub 2012 Mar 13.

Background: Successful periodontal treatment requires a commitment to regular lifelong maintenance and may be perceived by patients to be costly. This study calculates the total lifetime cost of periodontal treatment in the setting of a specialist periodontal practice and investigates the cost implications of choosing not to proceed with such treatment.

Methods: Data from patients treated in a specialist practice in Norway were used to calculate the total lifetime cost of periodontal treatment that included baseline periodontal treatment, regular maintenance, retreatment, and replacing teeth lost during maintenance. Incremental costs for alternative strategies based on opting to forego periodontal treatment or maintenance and to replace any teeth lost with either bridgework or implants were calculated.

Results: Patients who completed baseline periodontal treatment but did not have any additional maintenance or retreatment could replace only three teeth with bridgework or two teeth with implants before the cost of replacing additional teeth would exceed the cost of lifetime periodontal treatment. Patients who did not have any periodontal treatment could replace ≤ 4 teeth with bridgework or implants before a replacement strategy became more expensive.

Conclusions: Within the limits of the assumptions made, periodontal treatment in a Norwegian specialist periodontal practice is cost-effective when compared to an approach that relies on opting to replace teeth lost as a result of progressive periodontitis with fixed restorations. In particular, patients who have initial comprehensive periodontal treatment but do not subsequently comply with maintenance could, on average, replace ≤ 3 teeth with bridgework or two teeth with implants before this approach would exceed the direct cost of lifetime periodontal treatment in the setting of the specialist practice studied.
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http://dx.doi.org/10.1902/jop.2012.110689DOI Listing
December 2012

Mapping biological to clinical phenotypes during the development (21 days) and resolution (21 days) of experimental gingivitis.

J Clin Periodontol 2012 Feb 12;39(2):123-31. Epub 2011 Dec 12.

Unilever Oral Care, Bebington, UK.

Aim: To characterize and map temporal changes in the biological and clinical phenotype during a 21-day experimental gingivitis study.

Materials And Methods: Experimental gingivitis was induced over 21 days in healthy human volunteers (n = 56), after which normal brushing was resumed (resolution phase). Gingival and plaque indices were assessed. Gingival crevicular fluid was collected from four paired test and contra-lateral control sites in each volunteer during induction (Days 0, 7, 14 and 21) and resolution (Days 28 and 42) of experimental gingivitis. Fluid volumes were measured and a single analyte was quantified from each site-specific, 30s sample. Data were evaluated by analysis of repeated measurements and paired sample tests.

Results: Clinical indices and gingival crevicular fluid volumes at test sites increased from Day 0, peaking at Day 21 (test/control differences all p < 0.0001) and decreased back to control levels by Day 28. Levels of four inflammatory markers showed similar patterns, with significant differences between test and control apparent at Day 7 (substance P, cathepsin G, interleukin-1β, elastase: all p < 0.03) and peaking at Day 21 (all p < 0.002). Levels of α-1-antitrypsin showed no pattern.

Conclusions: Levels of substance P, cathepsin G, interleukin-1β and neutrophil elastase act as objective biomarkers of gingival inflammation induction and resolution that typically precede phenotypical changes.
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http://dx.doi.org/10.1111/j.1600-051X.2011.01825.xDOI Listing
February 2012

Human dental pulp fibroblasts express the "cold-sensing" transient receptor potential channels TRPA1 and TRPM8.

J Endod 2011 Apr;37(4):473-8

School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, Northern Ireland.

Introduction: Transient receptor potential (TRP) channels comprise a group of nonselective calcium-permeable cationic channels, which are polymodal sensors of environmental stimuli such as thermal changes and chemicals. TRPM8 and TRPA1 are cold-sensing TRP channels activated by moderate cooling and noxious cold temperatures, respectively. Both receptors have been identified in trigeminal ganglion neurones, and their expression in nonneuronal cells is now the focus of much interest. The aim of this study was to investigate the molecular and functional expression of TRPA1 and TRPM8 in dental pulp fibroblasts.

Methods: Human dental pulp fibroblasts were derived from healthy molar teeth. Gene and protein expression was determined by polymerase chain reaction and Western blotting. Cellular localization was investigated by immunohistochemistry, and TRP functionality was determined by Ca(2+) microfluorimetry.

Results: Polymerase chain reaction and Western blotting showed gene and protein expression of both TRPA1 and TRPM8 in fibroblast cells in culture. Immunohistochemistry studies showed that TRPA1 and TRPM8 immunoreactivity co-localized with the human fibroblast surface protein. In Ca(2+) microfluorimetry studies designed to determine the functionality of TRPA1 and TRPM8 in pulp fibroblasts, we showed increased intracellular calcium ([Ca(2+)](i)) in response to the TRPM8 agonist menthol, the TRPA1 agonist cinnamaldehyde, and to cool and noxious cold stimuli, respectively. The responses to agonists and thermal stimuli were blocked in the presence of specific TRPA1 and TRPM8 antagonists.

Conclusions: Human dental pulp fibroblasts express TRPA1 and TRPM8 at the molecular, protein, and functional levels, indicating a possible role for fibroblasts in mediating cold responses in human teeth.
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http://dx.doi.org/10.1016/j.joen.2010.12.017DOI Listing
April 2011

Human odontoblasts express functional thermo-sensitive TRP channels: implications for dentin sensitivity.

Pain 2011 Oct 17;152(10):2211-2223. Epub 2010 Dec 17.

School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK Laboratoire IMEB, Faculté d Odontologie, Université de la Méditerranée, Marseille, France.

Odontoblasts form the outermost cellular layer of the dental pulp where they have been proposed to act as sensory receptor cells. Despite this suggestion, evidence supporting their direct role in mediating thermo-sensation and nociception is lacking. Transient receptor potential (TRP) ion channels directly mediate nociceptive functions, but their functional expression in human odontoblasts has yet to be elucidated. In the present study, we have examined the molecular and functional expression of thermo-sensitive TRP channels in cultured odontoblast-like cells and in native human odontoblasts obtained from healthy wisdom teeth. PCR and western blotting confirmed gene and protein expression of TRPV1, TRPA1 and TRPM8 channels. Immunohistochemistry revealed that these channels were localised to odontoblast-like cells as determined by double staining with dentin sialoprotein (DSP) antibody. In functional assays, agonists of TRPV1, TRPA1 and TRPM8 channels elicited [Ca2+]i transients that could be blocked by relevant antagonists. Application of hot and cold stimuli to the cells also evoked rises in [Ca2+]i which could be blocked by TRP-channel antagonists. Using a gene silencing approached we further confirmed a role for TRPA1 in mediating noxious cold responses in odontoblasts. We conclude that human odontoblasts express functional TRP channels that may play a crucial role in mediating thermal sensation in teeth. Cultured and native human odontoblasts express functional TRP channels that may play a crucial role in mediating thermal sensation in teeth.
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http://dx.doi.org/10.1016/j.pain.2010.10.016DOI Listing
October 2011

Replication of the association of chromosomal region 9p21.3 with generalized aggressive periodontitis (gAgP) using an independent case-control cohort.

BMC Med Genet 2010 Aug 9;11:119. Epub 2010 Aug 9.

Interfaculty Institute for Genetics and Functional Genomics, Department of Functional Genomics, Ernst-Moritz-Arndt-University Greifswald, Greifswald, Germany.

Background: The human chromosomal region 9p21.3 has been shown to be strongly associated with Coronary Heart Disease (CHD) in several Genome-wide Association Studies (GWAS). Recently, this region has also been shown to be associated with Aggressive Periodontitis (AgP), strengthening the hypothesis that the established epidemiological association between periodontitis and CHD is caused by a shared genetic background, in addition to common environmental and behavioural risk factors. However, the size of the analyzed cohorts in this primary analysis was small compared to other association studies on complex diseases. Using our own AgP cohort, we attempted to confirm the described associations for the chromosomal region 9p21.3.

Methods: We analyzed our cohort consisting of patients suffering from the most severe form of AgP, generalized AgP (gAgP) (n = 130) and appropriate periodontally healthy control individuals (n = 339) by genotyping four tagging SNPs (rs2891168, rs1333042, rs1333048 and rs496892), located in the chromosomal region 9p21.3, that have been associated with AgP.

Results: The results confirmed significant associations between three of the four SNPs and gAgP. The combination of our results with those from the study which described this association for the first time in a meta-analysis of the four tagging SNPs produced clearly lower p-values compared with the results of each individual study. According to these results, the most plausible genetic model for the association of all four tested SNPs with gAgP seems to be the multiplicative one.

Conclusion: We positively replicated the finding of an association between the chromosomal region 9p21.3 and gAgP. This result strengthens support for the hypothesis that shared susceptibility genes within this chromosomal locus might be involved in the pathogenesis of both CHD and gAgP.
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http://dx.doi.org/10.1186/1471-2350-11-119DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2924866PMC
August 2010

Long-term outcomes for cross-arch stabilizing bridges in periodontal maintenance patients--a retrospective study.

J Clin Periodontol 2010 Mar 13;37(3):299-304. Epub 2010 Jan 13.

Kvednabekkvn 4 N-4370 Egersund Norway.

Background: Cross-arch bridges are used to stabilize teeth for patients with reduced periodontal support. Little is known about technical or biological complications, whether teeth and implants can be combined in this type of bridge and the long-term effects on tooth loss.

Materials And Methods: All patients treated in a specialist periodontal practice who received cross-arch stabilizing bridgework and were subsequently maintained for at least 7 years were included in the study. The patients were selected from all patients who underwent initial periodontal therapy after 1986 in a Norwegian periodontal practice. The bridges were assessed for biological and technical complications. Bridges retained by teeth or by a combination of teeth and implants were included in the study.

Results: Ninety-four rigid fixed bridges (77 teeth supported, 17 teeth and implant supported) in 80 patients (46 females, 34 males) were observed for an average of 10 years (range 7-22 years). In four patients, a bridge became loose and had to be re-cemented, and in one case the metal framework of a bridge fractured and the bridge had to be remade. In total, eight abutment teeth were lost from five patients but no implant abutments were lost. Overall, a higher rate of tooth loss was observed for patients provided with stabilizing bridges compared with control maintenance patients not treated with bridgework (p<0.0001); however, the rates in both groups were very low.

Conclusion: Cross-arch stabilizing bridges constructed for periodontal patients as part of their periodontal maintenance therapy had few complications and were associated with low rates of abutment tooth loss. Combining teeth and implants did not affect the performance of these bridges.
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http://dx.doi.org/10.1111/j.1600-051X.2009.01528.xDOI Listing
March 2010

Antioxidants and periodontitis in 60-70-year-old men.

J Clin Periodontol 2009 Oct 23;36(10):843-9. Epub 2009 Aug 23.

Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen's University, Belfast, Northern Ireland, UK.

Objective: The aim was to investigate the association between periodontal health and the serum levels of various antioxidants including carotenoids, retinol and vitamin E in a homogenous group of Western European men.

Materials And Methods: A representative sample of 1258 men aged 60-70 years, drawn from the population of Northern Ireland, was examined between 2001 and 2003. Each participant had six or more teeth, completed a questionnaire and underwent a clinical periodontal examination. Serum lipid-soluble antioxidant levels were measured by high-performance liquid chromatography with diode array detection. Multivariable analysis was carried out using logistic regression with adjustment for possible confounders. Models were constructed using two measures of periodontal status (low- and high-threshold periodontitis) as dependent variables and the fifths of each antioxidant as a predictor variable.

Results: The levels of alpha- and beta-carotene, beta-cryptoxanthin and zeaxanthin were highly significantly lower in the men with low-threshold periodontitis (p<0.001). These carotenoids were also significantly lower in high-threshold periodontitis. There were no significant differences in the levels of lutein, lycopene, alpha- and gamma-tocopherol or retinol in relation to periodontitis. In fully adjusted models, there was an inverse relationship between a number of carotenoids (alpha- and beta-carotene and beta-cryptoxanthin) and low-threshold periodontitis. beta-Carotene and beta-cryptoxanthin were the only antioxidants that were associated with an increased risk of high-threshold severe periodontitis. The adjusted odds ratio for high-threshold periodontitis in the lowest fifth relative to the highest fifth of beta-cryptoxanthin was 4.02 (p=0.003).

Conclusion: It is concluded that low serum levels of a number of carotenoids, in particular beta-cryptoxanthin and beta-carotene, were associated with an increased prevalence of periodontitis in this homogenous group of 60-70-year-old Western European men.
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http://dx.doi.org/10.1111/j.1600-051X.2009.01468.xDOI Listing
October 2009

Neuropeptides regulate expression of angiogenic growth factors in human dental pulp fibroblasts.

J Endod 2009 Jun 19;35(6):829-33. Epub 2009 Apr 19.

Department of Restorative Dentistry, School of Dentistry, Royal Group of Hospitals, Belfast, United Kingdom.

Introduction: Neuropeptides play an important role in inflammation and repair and have been implicated in mediating angiogenesis. Pulp fibroblasts express neuropeptide receptors, and the aim of this research was to investigate whether neuropeptides could regulate angiogenic growth factor expression in vitro

Methods: An angiogenic array was used to determine the levels of 10 angiogenic growth factors expressed by human pulp fibroblasts.

Results: Pulp fibroblasts were shown to express angiogenin, angiopoietin-2, epidermal growth factor, basic fibroblast growth factor, heparin-binding epidermal growth factor, hepatocyte growth factor, leptin, platelet-derived growth factor, placental growth factor, and vascular endothelial growth factor. Furthermore, the neuropeptides substance P, calcitonin gene-related peptide, vasoactive intestinal polypeptide, and neuropeptide Y altered angiogenic growth factor expression in vitro.

Conclusions: The regulation of angiogenic growth factor expression by neuropeptides suggests a novel role for neuropeptides in pulpal inflammation and repair.
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http://dx.doi.org/10.1016/j.joen.2009.03.005DOI Listing
June 2009

Neuropeptide Y (NPY) and NPY Y1 receptor in periodontal health and disease.

Arch Oral Biol 2009 Mar 17;54(3):258-62. Epub 2008 Nov 17.

Oral Science Research Centre, School of Medicine and Dentistry, Queen's University, Grosvenor Road, Belfast BT126BP, Northern Ireland, UK.

Objectives: Neuropeptide Y (NPY) coordinates inflammation and bone metabolism which are central to the pathogenesis of periodontitis. The present study was designed to determine whether NPY was quantifiable in human gingival crevicular fluid (GCF) and to test the null hypothesis that GCF levels of NPY were the same in periodontal health and disease. A subsidiary aim was to determine the potential functionality of released NPY by detecting the presence of NPY Y1 receptors in gingival tissue.

Design: The periodontitis group consisted of 20 subjects (10 females and 10 males) mean age 41.4 (S.D. 9.6 years). The control group comprised 20 subjects (10 females and 10 males) mean age 37.4 (S.D. 11.7 years). NPY levels in GCF were measured in periodontal health and disease by radioimmunoassay. NPY Y1 receptor expression in gingival tissue was determined by Western blotting of membrane protein extracts from healthy and inflamed gum.

Results: Healthy sites from control subjects had significantly higher levels of NPY than diseased sites from periodontitis subjects. NPY Y1 receptor protein was detected in both healthy and inflamed gingival tissue by Western blotting.

Conclusions: The significantly elevated levels of NPY in GCF from healthy compared with periodontitis sites suggests a tonic role for NPY, the functionality of which is indicated by the presence of NPY Y1 receptors in local gingival tissue.
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http://dx.doi.org/10.1016/j.archoralbio.2008.10.002DOI Listing
March 2009

Persistently raised C-reactive protein levels are associated with advanced periodontal disease.

J Clin Periodontol 2008 Sep 21;35(9):741-7. Epub 2008 Jul 21.

Oral Science Research Centre, Queen's University, Belfast, UK.

Objective: The aim was to investigate whether there was an association between periodontitis or tooth loss in a homogeneous group of 60-70-year-old Western European men and either a sustained high or low level of C-reactive protein (CRP).

Material And Methods: Men enrolled in a cohort study of cardiovascular disease in Northern Ireland were screened in 1990-1994 and rescreened in 2001-2004, when a periodontal examination was completed. High-sensitivity CRP was measured from fasting blood samples. There were 806 men with six or more teeth who had either a high level (>3 mg/l) or a lower level of CRP at both time points. Multivariate analysis was carried out using logistic regression with adjustment for possible confounders. Models were constructed with the CRP level as the outcome variable and various measures of periodontal status (low and high threshold periodontitis) or tooth loss as predictor variables. Confounders included in the analysis were known cardiovascular risk factors of age, smoking, diabetes, BMI and socioeconomic status.

Results: There were 67 men who had a high value of CRP (>3 mg/l) and 739 men who had a CRP value
Conclusion: There was an association between advanced periodontitis and elevated CRP levels as measured at two time points at a 10-year interval in the 60-70-year-old European males investigated. This association was adjusted for various cardiovascular risk factors. There was also an association between high levels of tooth loss and high CRP in the men studied.
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http://dx.doi.org/10.1111/j.1600-051X.2008.01288.xDOI Listing
September 2008