The interleukin-1 genotype as a severity factor in adult periodontal disease

Contemporary concepts in the diagnosis of periodontal disease

Periodontitis is an inflammatory disease of bacterial origin that results in the progressive destruction of the tissues that support the teeth, specifically the gingiva, periodontal ligament, and alveolar bone. The diagnosis of periodontal disease currently relies almost exclusively on clinical parameters and traditional dental radiography. In this article, the authors review current diagnostic techniques and present new approaches and technologies that are being developed to improve assessment of this common condition.

Relationship of tooth loss to mild memory impairment and cognitive impairment: findings from the Fujiwara-kyo study

Background

This cross-sectional study investigated the relationship between the number of remaining teeth to mild memory impairment (MMI), which is a preclinical stage of dementia, and to cognitive impairment.

Methods

The subjects were aged 65 years or older and were grouped according to their score for the Mini-Mental State Examination (MMSE), the three-word delayed recall test in the MMSE, and the Geriatric Depression Scale into the control group (n = 3,696), the MMI group (n = 121), and the low MMSE score (23 or lower) group (n = 214). We collected data on the number of remaining teeth, the length of the edentulous period, health-related lifestyle, medical history, blood pressure, height, and body weight. Fasting venous blood samples were also obtained.

Results

Multiple logistic regression analysis, adjusted for depressive symptoms, age, sex, length of education, and other explanatory variables, revealed that the odds ratios of 0-10 remaining teeth to 22-32 remaining teeth were 1.679 (95% CI 1.073-2.627) for MMI and 2.177 (95% CI 1.510-3.140) for a low MMSE score. A significant relationship was also found between the length of the edentulous period and the risk of a low MMSE score (odds ratio 3.102, 95% CI 1.432-6.720) (15 years or more/less than 15 years).

Conclusions

Our findings suggest that tooth loss is associated with cognitive function.

The association of aggressive and chronic periodontitis with systemic manifestations and dental anomalies in a jordanian population: a case control study

Background

The relationship between dental anomalies and periodontitis has not been documented by earlier studies. Although psychological factors have been implicated in the etiopathogenesis of periodontitis, very little information has so far been published about the association of anxiety and depression with aggressive periodontitis. The aim of this study was to investigate the association of chronic periodontitis and aggressive periodontitis with certain systemic manifestations and dental anomalies.

Methods

A total of 262 patients (100 chronic periodontitis, 81 aggressive periodontitis and 81 controls), attending the Periodontology clinics at Jordan University of Science and Technology, Dental Teaching Centre) were included. All subjects had a full periodontal and radiographic examination to assess the periodontal condition and to check for the presence of any of the following dental anomalies: dens invaginatus, dens evaginatus, congenitally missing lateral incisors or peg-shaped lateral incisors. Participants were interrogated regarding the following: depressive mood, fatigue, weight loss, or loss of appetite; and their anxiety and depression status was assessed using the Hospital Anxiety and Depression (HAD) scale.

Results

Patients with aggressive periodontitis reported more systemic symptoms (51%) than the chronic periodontitis (36%) and control (30%) patients (p < 0.05). Aggressive periodontitis patients had a higher tendency for both anxiety and depression than chronic periodontitis and control patients. Dental anomalies were significantly (p < 0.05) more frequent among both of chronic and aggressive periodontitis patients (15% and 16%, respectively), compared to controls.

Conclusion

In this group of Jordanians, systemic symptoms were strongly associated with aggressive periodontitis, and dental anomalies were positively associated with both aggressive and chronic periodontitis.

Haplotypes in the interleukin 8 gene and their association with chronic periodontitis susceptibility

Interleukin-8 (IL-8), which is responsible for the migration and activation of neutrophils, is an important inflammatory mediator involved in the initiation and amplification of acute inflammatory reactions and chronic inflammatory processes. IL-8 plays an important role in periodontitis, an inflammatory disease characterized by the loss of connective tissue and alveolar bone. The aim of this study was to investigate whether the SNPs rs2227307 (+396) and rs2227306 (+781), and the haplotypes they formed together with the previously investigated rs4073 (-251), were associated with chronic periodontitis susceptibility. Clinical periodontal exams were performed and DNA samples were collected from 493 individuals (223 with periodontitis and 270 controls). Associations between SNPs, haplotypes, and subject phenotypes were analyzed using the χ(2) test followed by multivariate logistic regression modeling. We conclude that the +396TT genotype and the haplotypes ATC/TTC and AGT/TGC were significantly associated with chronic periodontitis susceptibility in Brazilians.

Association of interleukin-1 receptor antagonist gene polymorphisms with generalized aggressive periodontitis in an Iranian population

BACKGROUND

Periodontitis is a multifactorial disease that occurs in the presence of bacteria, environmental factors, and genetic predispositions. It is suggested that polymorphisms in the interleukin-1 (IL1) receptor antagonist gene have an important role in the susceptibility of the host to periodontitis. This study investigates the association of a variable number of tandem repeat polymorphism in the IL1RN gene with generalized aggressive periodontitis (GAgP).

METHODS

Sixty-six subjects with GAgP and 56 periodontally healthy subjects took part in the study. All subjects were of Iranian Khorasanian (north-east province of Iran) descent. Subjects were identified through clinical examinations and radiographs at the Mashad Dental School and Dental Research Center. DNA was extracted from peripheral blood cells, and different genotypes were detected using polymerase chain reaction amplification and fragment-size analysis. Data were analyzed using the chi(2) test.

RESULTS

The frequencies of the IL1RN genotype A1A2 (chi(2) test; P = 0.001) and allele A2 (chi(2) test; P = 0.006) were found to be significantly increased in patients with GAgP compared to normal subjects.

CONCLUSION

These findings suggest that the polymorphic IL1RN gene is a risk determinant for generalized aggressive periodontitis in the Iranian Khorasanian population.

Relationship between obesity and physical fitness and periodontitis

BACKGROUND

Obesity and exercise are important elements associated with lifestyle-related diseases, and studies suggested that these factors may also be related to periodontitis. This study investigates the relationship between obesity and physical fitness and periodontitis.

METHODS

One thousand, one hundred and sixty Japanese subjects, aged 20 to 77 years, who participated in health examinations at Fukuoka Health Promotion Center were analyzed. Periodontal conditions were evaluated using the Community Periodontal Index (CPI), and subjects with > or =3 sextants of CPI code 3 or 4 were defined as having severe periodontitis. We used the body mass index (BMI) and percentage of body fat as indicators of obesity and estimated the maximal oxygen consumption (VO(2max)) during exercise as an indicator of physical fitness. We divided these variables into quintiles. We examined the single effect and interactions of the obesity index and VO(2max) on severe periodontitis.

RESULTS

The lowest quintile in BMI and the highest quintile in VO(2max) were inversely associated with severe periodontitis, singly, in multivariate logistic regression analyses. Subjects with the combined lowest quintile in BMI and the highest quintile in VO(2max) had a significantly lower risk of severe periodontitis compared to subjects with other combined quintiles in BMI and in VO(2max) (odds ratio: 0.17; 95% confidence interval: 0.05 to 0.55).

CONCLUSION

This study suggests that obesity and physical fitness may have some interactive effect on periodontal health status.

Saliva: diagnostics and therapeutic perspectives

For the past two decades, salivary diagnostic approaches have been developed to monitor oral diseases such as periodontal diseases and to assess caries risk. Recently, the combination of emerging biotechnologies and salivary diagnostics has extended the range of saliva-based diagnostics from the oral cavity to the whole physiologic system as most compounds found in blood are also present in saliva. Accordingly, saliva can reflect the physiologic state of the body, including emotional, endocrinal, nutritional and metabolic variations and acts as a source for the monitoring of oral and also systemic health. This review presents an update on the status of saliva diagnostics and delves into their applications to the discovery of biomarkers for cancer detection and therapeutic applications. Translating scientific findings of nucleic acids, proteins and metabolites in body fluids to clinical applications is a cumbersome and challenging journey. Our research group is pursuing the biology of salivary analytes and the development of technologies for detection of distinct biomarkers with high sensitivity and specificity. The avenue of saliva diagnostics incorporating transcriptomic, proteomic and metabolomic findings will enable us to connect salivary molecular analytes to monitor therapies, therapeutic outcomes, and finally disease progression in cancer.

Interleukin-8 gene promoter polymorphism (rs4073) may contribute to chronic periodontitis

BACKGROUND

The proinflammatory chemokine interleukin (IL)-8 is important in the regulation of the inflammatory response. Analyses of the single nucleotide polymorphism (SNP) reference sequence (rs) 4073 showed that the A allele upregulated IL-8 levels after stimulation with lipopolysaccharides. We investigated the association of the SNP rs4073 with chronic periodontitis.

METHODS

Genotyping was performed by a standard polymerase chain reaction-restriction fragment length polymorphism assay in 289 genomic DNA samples of healthy control subjects and patients with chronic periodontitis; analyses were adjusted by multivariate logistic regression modeling. A real-time polymerase chain reaction performance was used to detect levels of the IL-8 mRNA.

RESULTS

The analysis pointed to a statistically significant association of chronic periodontitis with the heterozygous TA genotype (P = 0.001); the results showed an increase in the frequency of the A allele in the diseased group (36% in the control group versus 48% in the periodontitis group). The higher levels of the IL-8 mRNA were found in the periodontitis group, mainly in individuals who presented the TA genotype (P = 0.03).

CONCLUSION

The SNP rs4073 was associated with chronic periodontitis in non-smoker Brazilian subjects because the frequency of the A allele was higher in the disease group than in the control group, and the TA genotype was associated with increased levels of IL-8 mRNA transcripts.

Inflammation and genetic risk indicators for early periodontitis in adults

BACKGROUND

This report is a further analysis of a study designed to determine clinical and microbial risk indicators for progressing periodontitis.

METHODS

One hundred ninety subjects who were periodontally healthy or had early signs of periodontitis (age range: 20 to 40 years) were monitored clinically at 6-month intervals followed by supragingival cleaning. At each visit, gingival crevicular fluid (GCF) and blood were collected for determination of interleukin (IL)-1β content (in GCF) and IL-1 genotype (in blood). Interproximal sites with a >1.5-mm increase in clinical attachment over 18 months were considered disease active. Characteristics were compared between active and inactive subjects.

RESULTS

IL-1β levels in GCF increased with the severity of disease and correlated well with clinical signs of incipient disease. However, the IL-1 genotype did not show any significant associations with disease or the extent of disease.

CONCLUSION

Indicators of inflammation may be important clinical determinants of future periodontal disease progression, but the IL-1 genotype was not a risk indictor for early (slight) periodontitis as defined in this subject population.

Heritability of alveolar bone loss from periodontal disease in a baboon population: a pilot study

BACKGROUND

Reports from studies of twins, disease aggregation in families, animal models for periodontal disease, and various genetic-analysis studies have determined that genetics plays a role in the susceptibility to periodontal disease. The purpose of this pilot study is to evaluate the effect of genetics on periodontal disease by evaluating the heritability of alveolar bone loss in a captive baboon population.

METHODS

A collection of baboon skulls from a pedigreed colony (for which scientists and veterinarians maintain complete genealogic and veterinary records) was obtained from the Southwest National Primate Research Center, San Antonio, Texas and used in this pilot study. Measurements of alveolar bone loss were performed on 390 dry baboon skulls. A periodontal probe was used to measure alveolar bone loss. Maximum likelihood methods (designed to handle complex genealogies) were used to determine the heritability of alveolar bone loss. This software used known pedigrees in the captive baboon sample and tested the relationship between pairwise kinship and alveolar bone loss data to determine the heritability of alveolar bone loss from periodontal disease.

RESULTS

Genetic data were available for 347 of the 390 specimens. Using age and sex as covariates, genetic analysis indicated a heritability of 35% (standard error = 20%; P = 0.01). Although gender was not a significant factor in periodontal disease (P = 0.96), age was highly significantly associated with periodontal disease (P <0.0001).

CONCLUSIONS

In this pilot study, analysis of alveolar bone loss measurements from captive baboons indicates that bone loss increases with age and that a portion of periodontal disease risk may be caused by genetic variance. These findings provide evidence that periodontal disease is heritable in captive baboons and indicate that a larger, more-detailed study is warranted.

Logic Forest: an ensemble classifier for discovering logical combinations of binary markers

MOTIVATION

Highly sensitive and specific screening tools may reduce disease -related mortality by enabling physicians to diagnose diseases in asymptomatic patients or at-risk individuals. Diagnostic tests based on multiple biomarkers may achieve the needed sensitivity and specificity to realize this clinical gain.

RESULTS

Logic regression, a multivariable regression method predicting an outcome using logical combinations of binary predictors, yields interpretable models of the complex interactions in biologic systems. However, its performance degrades in noisy data. We extend logic regression for classification to an ensemble of logic trees (Logic Forest, LF). We conduct simulation studies comparing the ability of logic regression and LF to identify variable interactions predictive of disease status. Our findings indicate LF is superior to logic regression for identifying important predictors. We apply our method to single nucleotide polymorphism data to determine associations of genetic and health factors with periodontal disease.

AVAILABILITY

LF code is publicly available on CRAN, http://cran.r-project.org/.

Alterações periodontais associadas às doenças sistêmicas em crianças e adolescentes

OBJETIVO: O objetivo deste estuo foi revisar na literatura a inter-relação entre condições sistêmicas e a ocorrência de doenças periodontais em crianças e adolescentes, destacando-se as manifestações periodontais frequentemente encontradas. FONTES DE DADOS: Artigos indexados nas bases de dados Medline, Lilacs e Bibliografia Brasileira em Odontologia, nos últimos 20 anos, além de referências clássicas. As palavraschave utilizadas foram: "doença periodontal", "periodontite", "doenças sistêmicas", "criança" e "adolescente". SÍNTESE DOS DADOS: Doenças sistêmicas como hipofosfatasia, histiocitose X, síndrome de Down, síndrome de Papillon-Lefèvre, síndrome de Ehlers-Danlos, síndrome de Chédiak-Higashi, leucemias, Aids e as deficiências quantitativas e qualitativas dos neutrófilos estão associadas ao aparecimento de alterações periodontais graves em crianças e adolescentes. Os estudos demonstraram a ocorrência de alteração periodontal na forma de periodontite em crianças e adolescentes com doenças sistêmicas, podendo levar à perda precoce de dentes. CONCLUSÕES: A ocorrência de alterações periodontais é observada em crianças e adolescentes com alterações sistêmicas, que manifestam desde inflamação gengival até formas mais destrutivas, como periodontites e perda precoce dos dentes.

Polymorphisms and haplotypes in the interleukin-4 gene are associated with chronic periodontitis in a Brazilian population

BACKGROUND

Some haplotypes in the interleukin-4 (IL4) gene were reported to influence IL-4 cytokine production and were associated with inflammatory diseases. Association studies focusing on IL4 gene polymorphisms and periodontal disease provided conflicting results. The aim of this study is to investigate whether IL4 gene polymorphisms and haplotypes were related to chronic periodontitis in a Brazilian population.

METHODS

The polymorphisms -590(C/T) and +33(C/T) in the IL4 gene were identified by polymerase chain reaction (PCR) and restriction fragment-length polymorphism methods; the variable number of tandem repeats (VNTR) was identified by PCR. To assess the differences between the periodontitis group (n = 125) and control group (n = 125), the chi(2) test was used to assess genotype and allele distributions of individual polymorphisms. For haplotypes reconstructed by an expectation-maximization algorithm, the CLUMP program and Fisher exact test were used. Multivariate logistic regression modeling was used to assess the association of age, gender, smoking status, and polymorphism/haplotype with periodontitis.

RESULTS

The -590(T), +33(C), and insertion (I) of 70-base pair (bp) alleles and genotypes were more prevalent in the periodontitis group, even after adjusting for covariates. The -590, +33, and insertion (TCI) haplotype was associated with a susceptibility to periodontitis (adjusted odds ratio [OR(adjusted)] = 2.68; 95% confidence interval [CI] = 1.50 to 4.80) as was the genotype TCI/CCI (OR(adjusted) = 5.27; 95% CI = 2.28 to 12.18), whereas the TTD (OR(adjusted) = 0.48; 95% CI = 0.26 to 0.91), CTI (OR(adjusted) = 0.28, 95% CI = 0.11 to 0.70), and TTD/CTI (OR(adjusted) = 0.29; 95% CI = 0.08 to 1.13) genotypes were a associated with protection against the development of chronic periodontitis.

CONCLUSION

Significant associations between alleles, genotypes, and haplotypes of polymorphisms in the IL4 gene and chronic periodontitis were verified in Brazilian individuals.

Association of haplotypes in the IL8 gene with susceptibility to chronic periodontitis in a Brazilian population

BACKGROUND

Interleukin 8 (IL-8) is a chemokine related to the initiation and amplification of acute and chronic inflammatory processes. Polymorphisms in the IL8 gene have been associated with inflammatory diseases. We investigated whether the -845(T/C) and -738(T/A) single nucleotide polymorphisms (SNPs) in the IL8 gene, as well as the haplotypes they form together with the previously investigated -353(A/T), are associated with susceptibility to chronic periodontitis.

METHODS

DNA was extracted from buccal epithelial cells of 400 Brazilian individuals (control n=182, periodontitis n=218). SNPs were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Disease associations were analyzed by the chi(2) test, Exact Fisher test and Clump program. Haplotypes were reconstructed using the expectation-maximization algorithm and differences in haplotype distribution between the groups were analyzed to estimate genetic susceptibility for chronic periodontitis development.

RESULTS

When analyzed individually, no SNPs showed different distributions between the control and chronic periodontitis groups. Although, nonsmokers carrying the TTA/CAT (OR=2.35, 95% CI=1.03-5.36) and TAT/CTA (OR=6.05, 95% CI=1.32-27.7) haplotypes were genetically susceptible to chronic periodontitis. The TTT/TAA haplotype was associated with protection against the development of periodontitis (for nonsmokers OR=0.22, 95% CI=0.10-0.46).

CONCLUSION

Although none of the investigated SNPs in the IL8 gene was individually associated with periodontitis, some haplotypes showed significant association with susceptibility to, or protection against, chronic periodontitis in a Brazilian population.

Pathogen-mediated inflammatory atherosclerosis is mediated in part via Toll-like receptor 2-induced inflammatory responses

Studies in humans have established that polymorphisms in genes encoding the innate immune Toll-like receptors (TLRs) are associated with inflammatory atherosclerosis. In hyperlipidemic mice, TLR2 and TLR4 have been reported to contribute to atherosclerosis progression. Human and mouse studies support a role for the oral pathogen Porphyromonas gingivalis in atherosclerosis, although the mechanisms by which this pathogen stimulates inflammatory atherosclerosis via innate immune system activation is not known. Using a genetically defined apolipoprotein E-deficient (ApoE(-/-)) mouse model we demonstrate that pathogen-mediated inflammatory atherosclerosis occurs via both TLR2-dependent and TLR2-independent mechanisms. P. gingivalis infection in mice possessing functional TLR2 induced the accumulation of macrophages as well as inflammatory mediators including CD40, IFN-gamma and the pro-inflammatory cytokines IL-1 beta, IL-6 and tumor necrosis factor-alpha in atherosclerotic lesions. The expression of these inflammatory mediators was reduced in atherosclerotic lesions from P. gingivalis-infected TLR2-deficient (TLR2(-/-)) mice. These studies provide a mechanistic link between an innate immune receptor and pathogen-accelerated atherosclerosis by a clinically and biologically relevant bacterial pathogen.

Mechanisms of oral bacteria-induced platelet activation

The oral cavity is inhabited by over 500 different bacterial species that normally exist in ecological balance both with each other and with the host. When this equilibrium is disturbed, an overgrowth of individual organisms can occur, which, in turn, can lead to the onset of pathological processes, notably dental caries and periodontitis. Generally, bacteraemias occur more frequently in individuals with periodontal disease, and these bacteraemias have been implicated in the development of a range of systemic diseases, including atherothrombotic disorders. The mechanism underlying this relationship remains to be precisely defined, although studies have shown a link between bacteria of oral origin and platelet activation. Several orally derived species of bacteria interact with platelets, including those of the Streptococcus ( Streptococcus sanguinis , Streptococcus mutans , Streptococcus agalactiae , Streptococcus pyogenes , Streptococcus gordonii , Streptococcus pneumoniae , Streptococcus mitis ) and Staphylococcus ( Staphylococcus epidermidis , Staphylococcus capitis ) genera, as well as Pseudomonas aeruginosa and Porphyromonas gingivalis . In addition, some members of both the Streptococcus and the Staphylococcus genera, as well as Porphyromonas gingivalis , can activate platelets in vitro. The current review describes the heterogeneous mechanisms of platelet activation employed by individual bacterial species. The pathological and clinical implications of platelet activation by orally derived bacteria are discussed.

Association of single nucleotide gene polymorphism at interleukin-1beta +3954, -511, and -31 in chronic periodontitis and aggressive periodontitis in Dravidian ethnicity

BACKGROUND

Interleukin (IL)-1beta gene polymorphisms are considered a potential risk factor for periodontal disease. The aim of this study is to identify the association of IL-1beta gene polymorphisms with chronic periodontitis and aggressive periodontitis in a Malayalam-speaking Dravidian population from South India.

METHODS

The case-control study consisted of 43 patients with chronic periodontitis and 54 patients with aggressive periodontitis as cases, and the control group consisted of 101 healthy subjects. All subjects were genotyped for IL-1beta +3954, -511, and -31 loci by polymerase chain reaction amplification followed by restriction enzyme digestion and gel electrophoresis. Genotype, allele, and haplotype analyses were done.

RESULTS

Analyses for allele and genotypes showed a high frequency of the C allele and CC genotype for single nucleotide polymorphism IL-1beta +3954 in the group with chronic periodontitis and no difference for patients with aggressive periodontitis compared to controls (P <0.05). Haplotype analysis showed that IL-1beta -31 and -511 were in strong linkage disequilibrium in all groups. The IL-1beta -31 allele T was in linkage with allele T of IL-1beta +3954 in the control group.

CONCLUSIONS

In the Malayalam-speaking Dravidian population, allele C of IL-1beta +3954 appeared to be an important risk factor for chronic periodontitis. The IL-1beta -31 allele T was in linkage with allele T of IL-1beta +3954 in the control group. No gene polymorphisms were found in patients with aggressive periodontitis. More studies with a larger sample size involving the entire cluster of the IL-1beta gene are necessary to determine the exact role of IL-1beta gene polymorphisms in periodontal disease.

Status of association studies linking diabetes mellitus and periodontal disease in India

BACKGROUND

The prevalence of diabetes mellitus (DM) and periodontal disease / periodontitis (PD) is high, and the association of these two as risk factors influencing each other has been recognized and is extensively documented. However, a majority of these association studies have been done in developed countries and / or in developing countries other than India.

OBJECTIVE

To review, quantify and qualify the status of the published indexed scientific literature regarding the bidirectional association of DM and PD in India.

METHOD

An internet search of the literature was conducted to examine relevant association studies of DM and PD in India. As a matter of interest, the related articles were searched manually from one non-indexed national (India) publication of periodontology until October 2008. Specific focus was on indexed literature and only these were considered for the review.

RESULT

Eleven pertinent indexed publications addressing the concern with regard to population in India were identified. Most of them were in agreement with the accepted mechanisms involving these two diseases, but more supported a unidirectional view of interaction, that is, advocating the role of DM in a worsened periodontal condition. One study with an opposite view was recognised.

CONCLUSION

The paucity of such research in India, which will be a hub of diabetics in the near future, reflects the need to make available a strong body of evidence in the indexed literature relating not only to DM and its 'sixth complication', PD, but also the strong influence of PD on DM.

IL-1 Gene Cluster is Not Linked to Aggressive Periodontitis

The interleukin-1 (IL-1) gene family has been associated with susceptibility to periodontal diseases, including aggressive periodontitis (AgP); however, the results are still conflicting. The present study investigated the association between IL-1 genes and AgP using 70 markers spanning the 1.1-Mb region, where the IL-1 gene family maps, and exploring both the linkage disequilibrium (LD) and the haplotype structure in a case-control study including 95 patients and 121 control individuals. No association between AgP and IL1A, IL1B, and IL1RN genes was found in either single-point or haplotype analyses. Also, the LD map of the region 2q13–14 under the Malécot model for multiple markers showed no causal association between AgP and polymorphisms within the region (p = 0.207). In conclusion, our findings failed to support the existence of a causative variant for generalized AgP within the 2q13–14 region in an Italian Caucasian population.

Non-surgical management of periodontal disease

Non-surgical removal of plaque and calculus has been part of the initial phase of the management of patients with gingivitis and periodontitis for decades. It consists of patient motivation and oral hygiene instruction as well as mechanical removal of supra and subgingival plaque deposits. The purpose of this review was to assess recent changes. The article reports on changes in our understanding of plaque as a biofilm, developments in patient plaque control, chemical plaque control and scaling instruments. It also comments on full-mouth disinfection, the use of lasers and host modulation. Modern technology has made removal of microbial deposits by the patient and dental professionals more efficient. However, other advancements need to be used in conjunction with mechanical debridement at this time.

Destructive effects of smoking on molecular and genetic factors of periodontal disease

Many epidemiological evidences have proven the association between smoking and periodontal disease. The causality can be further established by linking findings of traditional epidemiological studies with the developments in molecular techniques that occurred in the last decade. The present article reviews recent studies that address the effect of smoking on molecular and genetic factors in periodontal disease. Most findings support the fact that tobacco smoking modulates destruction of the periodontium through different pathways: microcirculatory and host immune systems, connective tissue, and bone metabolism. Although smokers experience an increased burden of inflammatory responses to microbial challenges compared to non-smokers, understanding the association between smoking and periodontal diseases involves substantial problems with respect to accuracy of measurements, and particularly, sampling of many subjects. It remains unclear whether genetic susceptibility to periodontal disease is influenced by exposure to smoking or the effect of smoking on periodontal disease is influenced by genetic susceptibility. Employment of molecular techniques may play a key role in further elucidation of mechanisms linking smoking and periodontal destruction, the direct relationship as environmental factors and indirect relationship through genetic factors.

Gene polymorphisms in chronic periodontitis

We aimed to conduct a review of the literature for gene polymorphisms associated with chronic periodontitis (CP) susceptibility. A comprehensive search of the literature in English was performed using the keywords: periodontitis, periodontal disease, combined with the words genes, mutation, or polymorphism. Candidate gene polymorphism studies with a case-control design and reported genotype frequencies in CP patients were searched and reviewed. There is growing evidence that polymorphisms in the IL1, IL6, IL10, vitamin D receptor, and CD14 genes may be associated with CP in certain populations. However, carriage rates of the rare (R)-allele of any polymorphism varied considerably among studies and most of the studies appeared under-powered and did not correct for other risk factors. Larger cohorts, well-defined phenotypes, control for other risk factors, and analysis of multiple genes and polymorphisms within the same pathway are needed to get a more comprehensive insight into the contribution of gene polymorphisms in CP.

TLR4 and IL-18 gene variants in chronic periodontitis: impact on disease susceptibility and severity

The aim of the study was to assess whether genotypes in the Toll-like receptor 4 gene and in the promoter of the interleukin-18 gene are associated with the susceptibility to chronic periodontitis. 108 chronic periodontitis patients and 76 controls were genotyped for c.896A>G/1196C>T (TLR4 gene) and for c.-368G>C/ c.-838C>A (IL-18 promoter). There were no significant differences in genotype and allele distributions between the study groups. Periodontitis severity in patients with TLR4 c.896AG/1196CT genotype was significantly higher than wildtype carriers. The percentage of teeth with clinical attachment loss > or = 5 mm was 77.3% and 58.8%, respectively (p < or = 0.006, t-test). All subjects were further classified into carriers and non-carriers of at least one variant of each gene. A logistic regression analysis adjusted for gender, smoking, and age showed no association between gene variant carrier status and periodontitis (OR = 1.98, 95% CI 0.61-6.39). The results did not show that IL-18 and TLR4 variants have an effect on the susceptibility to chronic periodontitis. Considering the low number of periodontitis patients carrying TLR4 variants (11%), a comparison of the periodontitis severity depending on the genotype has to be interpreted cautiously.

The biology, prevention, diagnosis and treatment of periodontal diseases: scientific advances in the United States

BACKGROUND

Major scientific advances in periodontology in the past 150 years have fundamentally changed how clinicians detect and treat periodontal diseases. These advances include the demonstration that gingivitis and periodontitis are biofilm-induced infections caused by components of the indigenous oral microbiota, and that host inflammatory-immunologic responses to these microbial challenges are responsible for most of the observed tissue damage.

TYPES OF STUDIES REVIEWED

In this brief overview, the authors focus on the discovery of the relationships between dental plaque and the host periodontal tissues. They highlight some of the pioneers in the United States who shaped new approaches to prevention and treatment of periodontal disease.

RESULTS

Biofilms that cause gingivitis and periodontitis are complex polymicrobial communities that are resistant to antimicrobial agents and host defense mechanisms. An increased understanding of natural inflammation-resolving mechanisms suggests that control of inflammation is at least as important as is antimicrobial therapy in the treatment of periodontal infections. Data from randomized controlled clinical trials have shown that most conventional forms of periodontal therapy are effective as long as patients comply with posttreatment maintenance programs.

CONCLUSIONS

Many mechanisms involved in the repair and regeneration of periodontal tissues have been identified. Results of laboratory studies of factors that enhance prevention and treatment of periodontal disease have made the transition to clinical practice. Advances in the fields of molecular biology, human genetics and stem cell biology have set the stage for significant discoveries that will pave the way for the development of procedures needed for the predictable regeneration of periodontal tissues. As a result, new generations of people in the United States can expect to retain a healthy and functional dentition for a lifetime.

The American Journal of Cardiology and Journal of Periodontology editors' consensus: periodontitis and atherosclerotic cardiovascular disease

ACKNOWLEDGMENT

This Editors' Consensus is supported by an educational grant from Colgate-Palmolive, Inc., New York, New York, and is based on a meeting of the authors held in Boston, Massachusetts, on January 9, 2009.

DISCLOSURE

Dr. Friedewald has received honoraria for speaking from Novartis, East Hanover, New Jersey. Dr. Kornman is a full-time employee and shareholder of Interleukin Genetics, Waltham, Massachusetts, which owns patents on genetic biomarkers for chronic inflammatory diseases. Dr. Genco is a consultant to Merck, Whitehouse Station, New Jersey. Dr. Ridker has received research support from AstraZeneca, Wilmington, Delaware; Novartis; Pfizer, New York, New York; Roche, Nutley, New Jersey; Sanofi-Aventis, Bridgewater, New Jersey; and Abbott Laboratories, Abbott Park, Illinois. Dr. Ridker has received non-financial research support from Amgen, Thousand Oaks, California. Dr. Ridker is a co-inventor on patents held by Brigham and Women's Hospital that relate to the use of inflammatory biomarkers in cardiovascular disease. Dr. Ridker is a research consultant for Schering-Plough, Kenilworth, New Jersey; Sanofi-Aventis; AstraZeneca; Isis, Carlsbad, California; Novartis; and Vascular Biogenics, Tel Aviv, Israel. Dr. Van Dyke is a co-inventor on patents held by Boston University, Boston, Massachusetts, that relate to inflammation control, including consulting fees. Dr. Roberts has received honoraria for speaking from Merck, Schering-Plough, AstraZeneca, and Novartis. All other individuals in a position to control content disclosed no relevant financial relationships.

Periodontal disease status in gullah african americans with type 2 diabetes living in South Carolina

BACKGROUND

African Americans have a disproportionate burden of diabetes. Gullah African Americans are the most genetically homogeneous population of African descent in the United States, with an estimated European admixture of only 3.5%. This study assessed the previously unknown prevalence of periodontal disease among a sample of Gullah African Americans with diabetes and investigated the association between diabetes control and the presence of periodontal disease.

METHODS

Two hundred thirty-five Gullah African Americans with type 2 diabetes were included. Diabetes control was assessed by percentage of glycosylated hemoglobin (HbA1c) and divided into three categories: well controlled, <7%; moderately controlled, 7% to 8.5%; and poorly controlled, >8.5%. Participants were categorized as healthy (no clinical attachment loss [AL] or bleeding on probing) or as having early periodontitis (clinical AL > or =1 mm in at least two teeth), moderate periodontitis (three sites with clinical AL > or =4 mm and at least two sites with probing depth [PD] > or =3 mm), or severe periodontitis (clinical AL > or =6 mm in at least two teeth and PD > or =5 mm in at least one site). Observed prevalences of periodontitis were compared to rates reported for the National Health and Nutrition Examination Survey (NHANES) studies.

RESULTS

All subjects had evidence of periodontal disease: 70.6% had moderate periodontitis and 28.5% had severe disease. Diabetes control was not associated with periodontal disease. The periodontal disease proportions were significantly higher than the reported national prevalence of 10.6% among African Americans without diabetes.

CONCLUSION

Our sample of Gullah African Americans with type 2 diabetes exhibited a higher prevalence of periodontal disease compared to African Americans, with and without diabetes, as reported in NHANES III and NHANES 1999-2000.

Genetic Risk Factors for Periodontitis in a Japanese Population

Genetic variants at multiple loci have been shown to be associated with susceptibility to periodontitis. To better assess the genetic risk factors for periodontitis, we performed a case-control study in 319 Japanese individuals with periodontitis (172 aggressive and 147 chronic disease) and 303 race-matched healthy control individuals. Thirty-five functional gene polymorphisms that had been previously associated with immune responses were genotyped. For all gene polymorphisms tested, no significant differences were observed in the allele frequencies of persons with aggressive, chronic, and combined (aggressive and chronic) periodontitis, compared with control individuals. Multiple logistic regression analysis revealed a significant association of the vitamin D receptor +1056 T/C polymorphism with susceptibility to chronic periodontitis, after adjustment for age, gender, and smoking status (P = 0.002). These results suggest that none of the polymorphisms tested was strongly associated with periodontitis in a Japanese population. However, the vitamin D receptor +1056 polymorphism may be related to chronic periodontitis.

The oral microbial consortium's interaction with the periodontal innate defense system

The oral microbial consortium is the most characterized polymicrobial microbial community associated with the human host. Extensive sampling of both microbial and tissue samples has demonstrated that there is a strong association between the type of microbial community found in the gingival crevice and the status of innate host mediator expression. The strong clinical association between the microbial community and the innate host response in both clinically healthy and diseased tissue suggests that the oral consortium has a direct effect on periodontal tissue expression of innate defense mediators. A preliminary study in germ-free mice has demonstrated that the oral commensal consortium has direct effect on IL-1beta expression, indicating that this microbial community may contribute to the strong protective status of healthy gingival tissue. Likewise, the lipopolysaccharide composition and invasion characteristics of Porphyromonas gingivalis, an oral bacterium strongly associated with periodontitis, suggest that it may be a keystone member of the oral microbial community and facilitate a destructive change in the protective gingival innate host status.

TNFA and IL10 gene polymorphisms are not associated with periodontitis in Brazilians

IL-10 and TNF-α are cytokines that have complex and opposing roles in the inflammatory responses. G/A polymorphisms at position –1082 of IL10 and –308 of TNFA genes have been reported to influence the expression of IL-10 and TNF-α, respectively. The aim of this study was to investigate the association between the IL10 (-1082) and TNFA (- 308) gene polymorphisms with different clinical forms or severity of periodontitis in a sample of Brazilian individuals. DNA was obtained from oral swabs of 165 Brazilian individuals, which were divided into three groups: individuals with chronic periodontitis, aggressive periodontitis and individuals without clinical evidence of periodontitis. Evaluation of IL10 and TNFA polymorphisms was performed by RFLP analysis. Statistical analysis of data was performed using the χ² likelihood ratio and Fisher`s exact test. No significant differences in the genotype and allele distribution of either IL10 or TNFA were observed among individuals with different clinical forms or with different degrees of severity of periodontitis. Moreover, combined analysis of IL10 and TNFA polymorphisms did not show any association with periodontal status. As conclusion, the IL10 and TNFA gene promoter polymorphisms investigated are not associated with different clinical forms of periodontitis or with severity of the disease in the Brazilian population polymorphisms.

How dental care can preserve and improve oral health

Oral health is associated with overall health, and lack of access to dental care has consequences that go far beyond aesthetics. Most oral diseases are preventable and are relatively easy and inexpensive to address at early stages. However, multiple barriers make dental care unreachable for a sizable portion of the United States population, who consequently has higher incidence and prevalence of disease. Achieving meaningful improvements in oral health status among these groups will require a revamping of the dental infrastructure, augmenting the productivity and skills of the dental workforce, and increasing the population's oral health literacy.