Analytical epidemiology of periodontitis

Impact of periodontitis definition in epidemiological research. Results from the EPIPAP study in postpartum women

The purpose of this investigation was to study the impact of using various definitions of periodontitis on the frequency of periodontitis and on the associations with some known risk factors for periodontitis in a population of postpartum women in France. A clinical examination was performed within 2-4 d postpartum in 932 at-term women at five maternity units. We studied six definitions of periodontitis; five were applicable if at least two teeth were found to have the following: (i) a proximal clinical attachment level (CAL) of ≥ 3 mm; (ii) a probing depth (PD) of ≥ 4 mm; (iii) a PD of ≥ 4 mm and a CAL of ≥ 3 mm at the same site; (iv) a proximal PD of ≥ 5 mm or a proximal CAL of ≥ 4 mm; or (v) a PD of ≥ 4 mm and a CAL ≥ 3 mm and bleeding on probing at the same site. The sixth definition required the involvement of four teeth with a PD of ≥ 4 mm and a CAL of ≥ 3 mm at the same site. Associations between case status according to each definition and maternal characteristics (age, educational level, smoking before pregnancy, and time since last dental visit) were analyzed using generalized estimating equation models. The definition of periodontitis had an impact on the frequency of periodontitis, which ranged from 12.1% to 37.7%, and produced different ORs for the associations with risk factors for periodontitis.

Prediction of future marginal bone level: a radiographic study

AIM

The aim of the study was to predict the marginal bone level at a 5-year follow-up based on the information available from an initial radiographic examination and to evaluate the precision of the prediction by comparing the predicted bone levels with those actually observed at the follow-up.

MATERIALS AND METHODS

In 1997, 616 randomly selected dentate individuals underwent a full-mouth radiographic survey. In 2003, 473 of those individuals (77%) participated in a second radiographic examination. Marginal bone level, caries lesions, fillings, crowns, root fillings and periapical status were recorded on all teeth. On the basis of data available from the first examination, a linear mixed model regression analysis with the tooth as the unit of analysis was used to predict the marginal bone level 5 years later.

RESULTS

Number of teeth, smoking, and also presence of apical periodontitis and crowns were associated with bone loss and could be used as predictors of future marginal bone level.

CONCLUSION

The analysis of all teeth showed that the number of tooth- and person-specific factors at the first examination influenced the prediction of the marginal bone level at the 5-year follow-up examination. However, the performance of the combined prediction model was less satisfactory.

Diabetes mellitus and periodontitis: a tale of two common interrelated diseases

Diabetes mellitus (a group of metabolic disorders characterized by hyperglycemia) and periodontitis (a microbially induced inflammatory disorder that affects the supporting structures of teeth) are both common, chronic conditions. Multiple studies have demonstrated that diabetes mellitus (type 1 and type 2) is an established risk factor for periodontitis. Findings from mechanistic studies indicate that diabetes mellitus leads to a hyperinflammatory response to the periodontal microbiota and also impairs resolution of inflammation and repair, which leads to accelerated periodontal destruction. The cell surface receptor for advanced glycation end products and its ligands are expressed in the periodontium of individuals with diabetes mellitus and seem to mediate these processes. The association between the two diseases is bidirectional, as periodontitis has been reported to adversely affect glycemic control in patients with diabetes mellitus and to contribute to the development of diabetic complications. In addition, meta-analyses conclude that periodontal therapy in individuals with diabetes mellitus can result in a modest improvement of glycemic control. The effect of periodontal infections on diabetes mellitus is potentially explained by the resulting increase in levels of systemic proinflammatory mediators, which exacerbates insulin resistance. As our understanding of the relationship between diabetes mellitus and periodontitis deepens, increased patient awareness of the link between diabetes mellitus and oral health and collaboration among medical and dental professionals for the management of affected individuals become increasingly important.

A population-based study of periodontal care among those with and without diabetes

BACKGROUND

Our objectives were to describe the prevalence of periodontal care (a marker of periodontitis) among persons with and without diabetes and to examine the association between periodontal care and diabetes.

METHODS

We conducted a cross-sectional analysis, using 5 years of electronic data from a population-based cohort (N = 46,132), aged 40 to 70 years, with dental and medical insurance, and ≥ 1 dental and ≥ 1 medical visit. Periodontal care (yes/no) was defined by dental claims codes for procedures used to manage periodontitis. The association between periodontal care and diabetes was determined using logistic regression adjusted for and stratified by age, sex, insurance type, smoking status, body mass index (BMI) (in kilograms per square meter), and resource utilization band (RUB) (a measure of expected health care utilization attributable to comorbidity).

RESULTS

Overall, 11.2% (5,153 of 46,132) met diabetes criteria. The age-adjusted prevalence of periodontal care among those with and without diabetes was 39.1% and 32.5%, respectively (P <0.0001). The association between diabetes and periodontal care decreased with increasing age (interaction, P <0.0001), adjusting for BMI and RUB. The aged-stratified, adjusted odds ratio (OR) for periodontal care associated with diabetes was highest among those aged 40 to 44 years [OR, 1.6; confidence interval (CI), 1.30 to 1.97] and lowest among those aged 60 to 64 years (OR, 0.97; CI, 0.81 to 1.15) and was significant only among those aged 40 to 54 years.

CONCLUSION

We found that the prevalence of periodontal care was significantly higher among those with diabetes compared to those without diabetes and that the magnitude of this association decreased with increasing age.

Risk assessment for clinical attachment loss of periodontal tissue in Korean adults

PURPOSE

The purpose of this study was to assess the prevalence and extent of clinical attachment loss of periodontal tissue and to find out variables related to clinical attachment loss (CAL) in Korean adults older than 40 years of age.

MATERIALS AND METHODS

Data were collected from 2,519 subjects who were part of a cohort study conducted in Ansan city by Korea University Medical School for Korean Genome project. Age, sex, smoking, drinking, fast glucose, blood pressure, obesity and total cholesterol levels were examined. The oral examination included probing pocket depth, gingival recession and CAL of Ramford's teeth. The severity of periodontitis was classified based on the mean value of CAL. The relationship between each risk factor and the severity of CAL was independently estimated using the chi-square test, the test or one-way ANOVA. Multiple regression analysis was used to determine the significance of each factor in the periodontal disease.

RESULTS

The prevalences of clinical attachment between 1 and 3 mm, between 3 and < 5 mm, and ≥ 5 mm were 80.27%, 16.75% and < 1%, respectively. Although the univariate analysis showed age, gender, smoking, fasting glucose, blood pressure and total cholesterol levels were significantly related to the severity of CAL, multiple regression analysis indicated that age (P < .0001), gender (P < .0001) and smoking (P < .05) were only significantly related.

CONCLUSION

Older age, male gender and smoking were significant risk factor for the increase of CAL, and these may be useful indicators of periodontitis high-risk groups.

Sex differences in destructive periodontal disease: a systematic review

BACKGROUND

Sexual dimorphisms exist in the prevalence and severity of many human conditions and diseases. Models of risk assessment for periodontitis, however, are inconsistent with respect to the inclusion of sex as a risk factor. A systematic review of the literature and meta-analyses estimates sex-related differences in the prevalence of periodontitis.

METHODS

MEDLINE, EMBASE, and SCOPUS databases were searched for population surveys (sample size >500, half-mouth minimum, clinical attachment level) containing prevalence data on destructive periodontal disease in males and females.

RESULTS

Data were stratified by disease thresholds (3, 4, 5, and 7 mm) representing 50,604 subjects from 12 population surveys meeting selection criteria. Using a ≥ 5-mm clinical attachment loss threshold, seven studies provided data, permitting computation of mean-weighted sex differences in prevalence. Four studies provided data enabling a meta-analysis of prevalence rates. Sex exhibited a significant association with prevalence, reflecting a 9% difference between males and females (37.4% versus 28.1%, respectively), although the overall effect of sex in the meta-analysis was comparatively small (d = 0.19; 95% confidence interval, 0.16 and 0.22). This mean difference in prevalence between males and females was similar regardless of severity of disease threshold and after adjustment for other risk factors.

CONCLUSIONS

Men appear at greater risk for destructive periodontal disease than women; however, men do not appear at higher risk for more rapid periodontal destruction than women.

Association between periodontitis and impaired fasting glucose and diabetes

OBJECTIVE

Many studies have reported that periodontal disease is associated with diabetes, but its relation with impaired fasting glucose (IFG) has been understudied. This study investigated the relationship between chronic periodontitis, IFG, and diabetes in the U.S. population.

RESEARCH DESIGN AND METHODS

Participants in the National Health and Nutrition Examination Survey III, aged ≥ 20 years, who received periodontal examinations and provided blood samples (n = 12,254) were grouped into quintiles of mean clinical attachment loss (CAL) and pocket depth, with the lowest category being the reference. Plasma fasting glucose was categorized into three groups (normal, <100 mg/dL; IFG, ≥ 100 but <126 mg/dL; and diabetic, ≥ 126 mg/dL). Sociodemographic factors and other potential risk factors were obtained by interview or examination. SAS 9.1 was used for statistical analysis accounting for the complex weighted sampling.

RESULTS

Participants in the top quintile category of CAL had higher prevalence odds of IFG (odds ratio [OR] 1.55 [95% CI 1.16-2.07]) and diabetes (4.77 [2.69-8.46]) after adjustment for related confounders, compared with those in the bottom quintile. The highest quintile of pocket depth was positively associated with IFG (1.39 [1.00-1.92]) and diabetes (1.63 [1.10-2.42]) compared with the lowest quintile. ORs for CAL increased from the lowest to the highest quintile (P value test for trend <0.01) for all outcomes. The ORs for pocket depth also tended to rise across quintiles.

CONCLUSIONS

Chronic periodontitis measured by CAL and pocket depth was positively associated in a linear relation with IFG and diabetes in U.S. adults.

Periodontal disease as a risk marker in coronary heart disease and chronic kidney disease

PURPOSE OF REVIEW

More than half a million Americans die each year from coronary heart disease (CHD), 26 million suffer from chronic kidney disease (CKD), and a large proportion have periodontal disease, a chronic infection of the tissues surrounding teeth. Chronic inflammation contributes to CHD and CKD occurrence and progression, and periodontal disease contributes to the cumulated chronic systemic inflammatory burden. This review examines recent evidence regarding the role of periodontal disease in CHD and CKD.

RECENT FINDINGS

Periodontal pathogens cause both local infection and bacteremia, eliciting local and systemic inflammatory responses. Periodontal disease is associated with the systemic inflammatory reactant C-reactive protein (CRP), a major risk factor for both CHD and CKD. Nonsurgical periodontal disease treatment is shown to improve periodontal health, endothelial function, levels of CRP, and other inflammatory markers. Evidence for the association of periodontal disease with CKD consists of a small body of literature represented mainly by cross-sectional studies. No definitive randomized controlled trials exist with either CHD or CKD as primary endpoints.

SUMMARY

Recent evidence links periodontal disease with CHD and CKD. Adding oral health self-care and referral for professional periodontal assessment and therapy to the repertoire of medical care recommendations is prudent to improve patients' oral health and possibly reduce CHD and CKD risk.

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.

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.

Analysis of socio-demographic and systemic health factors and the normative conditions of oral health care in a population of the Brazilian elderly

OBJECTIVE

To investigate the association of socio-demographic and systemic health factors according to the normative conditions of oral health care (dental caries, edentulism, periodontal disease and oral mucosal lesion) in elderly individuals.

MATERIAL AND METHODS

A cross-sectional study was carried out in a group of elderly with access to community health care (n = 200). The normative conditions of oral health were then investigated according to the WHO and the SB Brazil criteria. Bivariate analyses were evaluated by the chi-square test and Fisher's exact test. An estimation of prevalence for the covariates was performed using Poisson's regression models.

RESULTS

The prevalence of edentulism and oral mucosal lesions was detected in 58% and 21.5% of elderly patients, respectively. In the dentate subjects, the prevalence of dental caries and periodontal disease was 51.2% and 20.8%, respectively. Older men and individuals from lower-income groups exhibited a higher prevalence of dental caries. Elderly women, illiterate individuals, and individuals over the age of 65 years exhibited a higher prevalence of edentulism. Elderly 60-64 years old and those who are employed had a significant association with periodontal disease.

CONCLUSION

Socio-demographic factors were associated with some notable oral diseases in the elderly.

Periodontitis prevalence and severity in Indonesians with type 2 diabetes

BACKGROUND

The prevalence of diabetes mellitus type 2 (DM2) in Indonesia is high and still rising. Periodontitis is associated with DM2. No study has investigated this association in Indonesia, nor has any study investigated this association using a variety of methods to operationalize periodontitis. The present study compares prevalence and severity of periodontitis in patients with DM2 to healthy controls, using different methods to operationalize periodontitis.

METHODS

A total of 78 subjects with DM2 and 65 healthy control subjects underwent a full-mouth periodontal screening assessing probing depth, gingival recession, plaque index, and bleeding on probing. Using these measurements, the prevalence and severity of periodontitis was operationalized in various ways. Differences in the prevalence and severity of periodontitis between subjects with DM2 and healthy subjects were analyzed using univariate analyses. In regression analyses, the prevalence and severity of periodontitis were predicted on the basis of DM2 presence, controlling for confounders and effect modification.

RESULTS

Prevalence of periodontitis was significantly higher in subjects with DM2 compared to healthy subjects, showing odds ratios of 5.0 and 6.1. Likewise, periodontitis severity was significantly higher in subjects with DM2.

CONCLUSION

Indonesian subjects with DM2 had more prevalent and more severe periodontitis than healthy Indonesian subjects, independent of confounding factors or the methods used to operationalize periodontitis.

Interferon-γ +874A/T polymorphism in relation to generalized chronic periodontitis and the presence of periodontopathic bacteria

BACKGROUND

Interferon gamma (IFN-γ) is one of the key regulatory cytokines that has a significant effect on immune responses. It may be important in the chronic inflammatory diseases such as periodontitis in which increased IFN-γ levels were found. The aim of this study was to analyze +874A/T polymorphism in the IFN-γ gene and its associations with the presence of periodontopathic bacteria and susceptibility to generalized chronic periodontitis (CP).

METHODS

A total of 498 unrelated Czech white subjects were included in the present study. Genomic DNA was obtained from the peripheral blood of 244 patients with CP and 254 healthy subjects. The IFN-γ +874A/T polymorphism was determined by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Subgingival bacterial colonization (A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia, T. denticola, P. micros, F. nucleatum in subgingival pockets) was investigated by the DNA-microarray based periodontal pathogen detection kit in a subgroup of subjects (N=110).

RESULTS

Our results showed no differences in the allele and genotype frequencies of the IFN-γ +874A/T polymorphism between patients with CP and controls (P>0.05). Although we found significant differences in the occurrence of periodontal bacteria between patients with CP and healthy controls (from P<0.00001 to P<0.05), no significant association between IFN-γ +874A/T polymorphism and periodontal pathogens was observed in any group.

CONCLUSIONS

In conclusion, these findings indicate that putative functional variant in the IFN-γ is not associated with susceptibility to chronic periodontitis or microbial composition in the Czech population.

Fcgamma receptor polymorphisms and their association with periodontal disease: a meta-analysis

AIM

A systematic review and a meta-analysis were conducted in order to investigate the potential association of Fcgamma receptor (FcgammaR) polymorphisms with susceptibility to aggressive and chronic periodontal disease.

MATERIALS AND METHODS

A database search yielded a total of 17 studies involving 1685 cases and 1570 controls. Three polymorphisms were included in the meta-analysis: FcgammaRIIA H131R (rs1801274), FcgammaRIIIA F158V (rs396991) and FcgammaRIIIB NA1/NA2. Random-effect models were used in the analysis. Odds ratios (ORs) along with their 95% confidence intervals (CIs) were computed to compare the distribution of alleles and genotypes between cases and controls.

RESULTS AND CONCLUSIONS

The FcgammaRIIIB NA1/NA2 polymorphism was associated with both aggressive (per-allele OR 2.005, 95% CI: 1.044, 3.851) and chronic periodontitis (recessive contrast NA2NA2 versus NA1NA1+NA1NA2 OR 1.397, 95% CI: 1.039, 1.878). The analysis showed weak evidence for association between the FcgammaRIIA H131R polymorphism and aggressive periodontitis in Asians (R versus H allele OR 1.579, 95% CI: 1.025, 2.432). On the contrary, no relationship was identified between FcgammaRIIIA F158V and periodontal disease. Accumulating evidence from basic research makes the suggested association between FcgammaRIIIB NA1/NA2 polymorphism and periodontitis biologically plausible. Further research, however, is needed in order to assess possible gene-gene or gene-environment interactions (i.e. with smoking).

Periodontal health in Europe: future trends based on treatment needs and the provision of periodontal services--position paper 1

This review gives an update on recent epidemiologic data on periodontal diseases and a description of current periodontal services in Europe. A Medline search of articles published within the last decade with the keywords epidemiology, prevalence, periodontitis, tooth loss, and Europe was performed. Data on provision of dental services originated from international databases. Epidemiologic data on the prevalence of edentulism, the number of missing teeth, the prevalence of probing depth (Community Periodontal Index - CPI >or= 3 or Pocket Depth - PD >or= 4 mm), and clinical attachment loss (CAL >or= 4 mm) displayed a fragmentary picture within Europe. With respect to the limited data on periodontal health, Spain, Sweden, and Switzerland ranked as the healthiest among European countries in contrast to Germany where increased tooth loss and the highest prevalence of CAL >or= 4 mm were reported. The role of dental auxiliaries especially of dental hygienists and/or the medico-legal framework in which they work, appears to be an important factor in provision of effective periodontal care. Actual epidemiologic data on periodontal diseases are non-homogeneous and absent from several European countries. This emphasises the need for more national representative epidemiological studies with a uniform design to permit comparability between different nations. Merging actual epidemiologic data with former data on provision of periodontal care may help to explain differences in periodontal parameters on a population basis and to define future provision of dental care.

Methodological issues in epidemiological studies of periodontitis--how can it be improved?

Background

This position paper was commissioned by the European Association of Dental Public Health, which has established six working groups to investigate the current status of six topics related to oral public health. One of these areas is epidemiology of periodontal diseases.

Methods

Two theses "A systematic review of definitions of periodontitis and the methods that have been used to identify periodontitis" [1] and "Factors affecting community oral health care needs and provision" [2] formed the starting point for this position paper. Additional relevant and more recent publications were retrieved through a MEDLINE search.

Results

The literature reveals a distinct lack of consensus and uniformity in the definition of periodontitis within epidemiological studies. There are also numerous differences in the methods used. The consequence is that data from studies using differing case definitions and differing survey methods are not easily interpretable or comparable. The limitations of the widely used Community Periodontal Index of Treatment Need (CPITN) and its more recent derivatives are widely recognized. Against this background, this position paper reviews the current evidence base, outlines existing problems and suggests how epidemiology of periodontal diseases may be improved.

Conclusions

The remit of this working group was to review and discuss the existing evidence base of epidemiology of periodontal diseases and to identify future areas of work to further enhance it.

Maternal periodontitis and the causes of preterm birth: the case-control Epipap study

AIM

To analyse the association between maternal periodontitis and preterm birth (<37 weeks' gestation) according to the causes of preterm birth.

MATERIALS AND METHODS

Epipap is a case-control multi-centre study of singleton livebirths. One thousand one hundred and eight women with preterm deliveries and 1094 with deliveries at term (> or =37 weeks) at six French maternity units were included. Periodontal examinations after delivery identified localized and generalized periodontitis. Cases were classified according to four causes of preterm birth. Polytomous logistic regression analysis was used to control for confounders (maternal age, parity, nationality, educational level, marital status, employment during pregnancy, body mass index before pregnancy, smoking status) and the examiner.

RESULTS

Localized periodontitis was identified in 129 (11.6%) cases and in 118 (10.8%) control women and generalized periodontitis in 148 (13.4%) and 118 (10.8%), respectively. A significant association was observed between generalized periodontitis and induced preterm birth for pre-eclampsia [adjusted odds ratio 2.46 [95% confidence intervals (95% CI)1.58-3.83]. Periodontitis was not associated with spontaneous preterm birth or preterm premature rupture of membranes or with the other causes.

CONCLUSION

Maternal periodontitis is associated with an increased risk of induced preterm birth due to pre-eclampsia.

Substance use and periodontal disease among Australian Aboriginal young adults

AIM

To investigate the effects of tobacco, marijuana, alcohol and petrol sniffing on periodontal disease among Australian Aboriginal young adults.

DESIGN

Cross-sectional nested within a long-standing prospective longitudinal study. Setting Aboriginal communities in Australia's Northern Territory.

PARTICIPANTS

Members of the Aboriginal Birth Cohort study who were recruited from birth between January 1987 and March 1990 at the Royal Darwin Hospital, Northern Territory, Australia. Data were from wave III, when the mean age of participants was 18 years.

MEASUREMENTS

Clinical dental examination and self-report questionnaire.

FINDINGS

Of 425 participants with complete data, 26.6% had moderate/severe periodontal disease. There was elevated risk of periodontal disease associated with tobacco [prevalence ratio (PR) = 1.59, 95% CI = 1.06-2.40], marijuana (PR = 1.44, 95% CI = 1.05-1.97) and petrol sniffing (PR = 1.83, 95% CI = 1.08-3.11), but not alcohol (PR = 0.92, 95% CI = 0.67-1.27). Stratified analysis showed that the effect of marijuana persisted among tobacco users (PR = 1.47, 95% CI 1.03-2.11). It was not possible to isolate an independent effect of petrol sniffing because all petrol sniffers used both marijuana and tobacco, although among smokers of both substances, petrol sniffing was associated with an 11.8% increased prevalence of periodontal disease.

CONCLUSIONS

This is the first time that substance use has been linked with periodontal disease in a young Australian Aboriginal adult population, and the first time that petrol sniffing has been linked with periodontal disease in any population. The role of substance use in periodontal disease among this, and other, marginalized groups warrants further investigation.

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.

Periodontal health in children exposed to passive smoking

AIM

To determine (1) the cotinine levels of saliva, urine and gingival crevicular fluid (GCF) of children in families with and without smoking members and (2) a possible association between the periodontal health of the children and exposure to passive smoking.

MATERIAL AND METHODS

The study population comprised of 109 children in the age range 6-12 years. Children were classified as exposed to passive tobacco smoking (PTS-exposed, n=51) and as unexposed controls (PTS-unexposed, n=58). Plaque index, gingival index, bleeding on probing, probing depth and clinical attachment level (CAL) were recorded. GCF, saliva and urine samples were also collected. The levels of cotinine in these fluids were determined by enzyme-linked immunosorbent assay.

RESULTS

The mean salivary cotinine concentration was significantly increased in PTS-exposed children compared with PTS-unexposed children (p<0.05). Further, in a dose-dependent way, the mean salivary concentration was significantly higher in children whose father or mother was a smoker (p<0.05) as compared, respectively, with children whose fathers and mothers were non-smokers. The mean CAL was significantly less in PTS-exposed children compared with non-PTS-exposed children (0.09 mm; p<0.05) and also in children whose father was a smoker (p<0.05), but not in children whose mother was a smoker as compared with non-smoker fathers and mothers, respectively. The GCF cotinine levels were below the detection limits with the assay method that was used.

CONCLUSIONS

We have observed that children who are exposed to passive smoking have elevated cotinine levels in their saliva concomitant with a lowered CAL.

A systematic review of definitions of periodontitis and methods that have been used to identify this disease

OBJECTIVE

To perform a systematic review and critical analysis of the definitions of periodontitis and the methods which have been used to identify and measure this disease.

MATERIAL AND METHODS

Relevant publications were identified after searching MEDLINE, EMBASE, SCISEARCH and LILACS electronic databases. Screening of titles and abstracts and data extraction was conducted independently by two reviewers. To be included in the review, studies were required to define periodontitis and to indicate how it was measured. Studies that related purely to gingivitis, and/or intervention studies, and/or studies where prevalence or severity of periodontitis was not a principal outcome were excluded.

RESULTS

From a total of 34,72 titles and abstracts, 104 potentially relevant full text papers were identified. Of these, 15 met the criteria for inclusion in the final stage of the review. The survey revealed heterogeneity between the studies in the measurement tools used, particularly the types of probes and the sites and areas of the mouth that were assessed. There was also heterogeneity in the use of clinical attachment loss (CAL) and pocket probing depth (PPD) as criteria for periodontitis. In the 15 studies, the threshold for a diagnosis of periodontitis when CAL was the criterion ranged from 2 to > or =6 mm and when PPD was used, from 3 to > or =6 mm.

CONCLUSIONS

This review has confirmed previous work which has suggested that epidemiological studies of periodontal diseases are complicated by the diversity of methodologies and definitions used. The studies that were reviewed utilized a minimum diagnostic threshold defining periodontitis, at a given site in terms of CAL of 2 mm and PPD of 3 mm.

Identification of pathogen and host-response markers correlated with periodontal disease

BACKGROUND

Periodontitis is the major cause of tooth loss in adults and is linked to systemic illnesses, such as cardiovascular disease and stroke. The development of rapid point-of-care (POC) chairside diagnostics has the potential for the early detection of periodontal infection and progression to identify incipient disease and reduce health care costs. However, validation of effective diagnostics requires the identification and verification of biomarkers correlated with disease progression. This clinical study sought to determine the ability of putative host- and microbially derived biomarkers to identify periodontal disease status from whole saliva and plaque biofilm.

METHODS

One hundred human subjects were equally recruited into a healthy/gingivitis group or a periodontitis population. Whole saliva was collected from all subjects and analyzed using antibody arrays to measure the levels of multiple proinflammatory cytokines and bone resorptive/turnover markers.

RESULTS

Salivary biomarker data were correlated to comprehensive clinical, radiographic, and microbial plaque biofilm levels measured by quantitative polymerase chain reaction (qPCR) for the generation of models for periodontal disease identification. Significantly elevated levels of matrix metalloproteinase (MMP)-8 and -9 were found in subjects with advanced periodontitis with Random Forest importance scores of 7.1 and 5.1, respectively. The generation of receiver operating characteristic curves demonstrated that permutations of salivary biomarkers and pathogen biofilm values augmented the prediction of disease category. Multiple combinations of salivary biomarkers (especially MMP-8 and -9 and osteoprotegerin) combined with red-complex anaerobic periodontal pathogens (such as Porphyromonas gingivalis or Treponema denticola) provided highly accurate predictions of periodontal disease category. Elevated salivary MMP-8 and T. denticola biofilm levels displayed robust combinatorial characteristics in predicting periodontal disease severity (area under the curve = 0.88; odds ratio = 24.6; 95% confidence interval: 5.2 to 116.5).

CONCLUSIONS

Using qPCR and sensitive immunoassays, we identified host- and bacterially derived biomarkers correlated with periodontal disease. This approach offers significant potential for the discovery of biomarker signatures useful in the development of rapid POC chairside diagnostics for oral and systemic diseases. Studies are ongoing to apply this approach to the longitudinal predictions of disease activity.

Serum antibodies to periodontal bacteria as diagnostic markers of periodontitis

BACKGROUND

Assessment of periodontal conditions in epidemiologic studies usually requires a clinical examination, which is resource-intensive. We investigated the ability of serum immunoglobulin G (IgG) antibodies to periodontal bacteria to reflect clinical periodontal status.

METHODS

We used checkerboard immunoblotting to assess serum IgG levels to 19 species, including established/putative periodontal pathogens and non-pathogenic bacteria, in 5,747 dentate adults aged > or = 40 years who participated in the third National Health and Nutrition Examination Survey between 1988 and 1994. Three earlier described alternative definitions of periodontitis were used, based on specific combinations of probing depth and attachment level values. Optimized elevated titer thresholds and corresponding sensitivities and specificities were calculated for each definition. Titers significantly associated with periodontitis were identified in univariable and multivariable logistic regression models. Parsimonious models were subsequently developed using age, gender, race/ethnicity, education, smoking, and diagnosed diabetes.

RESULTS

In unadjusted models, high titers to Porphyromonas gingivalis were most strongly associated with periodontitis across all definitions (odds ratio, 2.07 to 2.74; P <0.05). In parsimonious models including demographic data, smoking, and diagnosed diabetes, high P. gingivalis titers were consistently associated with periodontitis, whereas high Eubacterium nodatum titers were associated with periodontal health in two of three definitions. Receiver operating characteristic curves for the parsimonious multivariable models showed that the area under the curve ranged between 0.72 and 0.78.

CONCLUSIONS

Serum IgG titers to selected periodontal species, combined with demographic and behavioral characteristics, resulted in a moderately accurate classification of periodontal status in epidemiologic studies. The external validity of these findings must be examined further.

Socio-demographic factors related to periodontal status and tooth loss of pregnant women in Mbale district, Uganda

Background

Information on the socio-behavioral distribution of periodontal status and tooth loss in pregnancy emanating from sub Saharan Africa is sparse. This study examined periodontal status and tooth loss in pregnant Ugandan women and assessed the relationship with socio-demographics factors, parity, dental care and oral hygiene.

Methods

Mothers were participants of a multicentre cluster-randomized behavioral intervention study (PROMISE-EBF Safety and Efficacy of Exclusive Breast feeding Promotion in the Era of HIV in Sub-Saharan Africa). In Uganda, these were pregnant women resident in Mbale district, recruited into the PROMISE EBF study between January 2006 and June 2008. A total of 886 women were eligible to participate of whom information became available for 877 (participation rate 98.9%, mean age 25.6) women who participated in the recruitment interview and 713 (mean age 25.5) women who got a clinical oral examination. Periodontal status was assessed using the Community Periodontal Index of Treatment Needs (CPITN).

Results

The prevalence of tooth loss was 35.7%, 0.6% presented with pockets shallow pockets (4–5 mm), whereas 3.3% and 63.4% displayed bleeding and calculus, respectively. A total of 32.7% were without any sign of periodontal disease. Binary logistic regression analyses revealed that older women, women from larger households and those presenting with microbial plaque were respectively, 3.4, 1.4 and 2.5 times more likely to have CPI score >0. Rural (OR = 0.9), nulliparous (OR = 0.4) and women who never visited a dentist (OR = 0.04) were less likely, whereas women from larger households (OR = 1.5) were more likely to have lost at least one tooth.

Conclusion

The results revealed moderate prevalence of bleeding and tooth loss, high prevalence of calculus, low frequency of pockets 4–5 mm. Disparity in pregnant women's oral health related to parity suggests that education of maternity care providers concerning oral health in pregnancy is warranted.

Trial registration

ClinicalTrials.gov Identifier NCT00397150

Periodontitis in pregnancy: clinical and serum antibody observations from a baboon model of ligature-induced disease

BACKGROUND

Chronic oral infections that elicit host responses leading to periodontal disease are linked with various sequelae of systemic diseases. This report provides seminal information on the clinical and adaptive immunologic characteristics of a baboon model of ligature-induced periodontitis during pregnancy.

METHODS

Female Papio anubis were evaluated for periodontal health at baseline. Ligatures were tied around selected teeth to initiate oral inflammation and periodontitis. Then the animals were bred. At midpregnancy ( approximately 90 days), a clinical evaluation was performed, and additional ligatures were tied on teeth in the contralateral quadrants to maintain progressing periodontitis throughout pregnancy. A final clinical evaluation was done for all experimental teeth after delivery, and ligatures were removed. Serum was collected at all sampling intervals for the determination of antibody levels to a group of 20 oral bacteria. Unligated animals served as controls.

RESULTS

At baseline, 16% of animals exhibited minimal plaque and gingival inflammation without periodontal disease. The remaining baboons demonstrated varying levels of inflammation/bleeding, and approximately 20% of the population had periodontal pocketing (>3 mm). Ligated animals expressed increased levels of inflammation and increased probing depths and clinical attachment loss (AL) and could be stratified into multiple subsets postligation based upon changes in clinical parameters at midpregnancy and at delivery. Baboons were categorized into disease susceptibility groups (periodontal disease susceptibility 1 through 4) that described the extent/severity of induced disease during pregnancy. Control animals showed minimal periodontal changes during gestation. Significant differences in serum antibody to multiple oral bacteria were found in animals presenting with periodontitis at baseline and during the 6 months of ligature-induced disease. A significant correlation to antibody to P. gingivalis, which was sustained throughout ligation and pregnancy, was observed with disease presentation.

CONCLUSIONS

The clinical presentation at baseline, reflecting the natural history of oral disease in these animals, suggests individual variation that is reflected in the characteristics of the adaptive immune responses to oral bacteria. The variability in the response to ligation with resulting periodontal disease provides a model to document prospectively the relationship between oral and systemic health outcomes.

Epigenetics and periodontal disease: future perspectives

Periodontitis is a multifactorial infection characterized by inflammation and destruction of tooth supporting tissues, as a result of the response of a susceptible host to bacterial challenge. Studies have demonstrated that epigenetic events are able to influence the production of cytokines, contributing to the development of inflammatory diseases. Epigenetic events act through the remodeling of chromatin and can selectively activate or inactivate genes, determining their expression. The epigenetic process, by inducing a change in cytokine profile, may subsequently influence the pathogenesis and determine the outcome of many infectious diseases. These findings may have relevance for inflammatory diseases in which the expression of cytokines is unregulated. The purpose of this review is to show evidence that supports the hypothesis that epigenetic alterations, such as hyper and hypomethylation, of cytokine genes, could help to understand the mechanisms related to periodontal disease activity. Therefore, epigenetics may have future impact on diagnosis and/or therapeutics of periodontal disease.

The association of MMP-9 and IL-18 gene promoter polymorphisms with gingivitis in adolescents

OBJECTIVE

Interleukin 18 (IL-18) is shown to be a proinflammatory cytokine that regulates the expression of matrix metalloproteinase 9 (MMP-9). The aim of this study was to test for differences between Czech adolescents with and without gingivitis in relation to MMP-9 and IL-18 polymorphisms.

DESIGN

A total of 298 Caucasian children, aged 11-13 years, were examined to assess gingival health. DNA for genetic analysis was obtained from buccal epithelial cells, and the MMP-9 -1562C/T and IL-18 -607A/C variants were identified with PCR-RFLP.

RESULTS

Gingivitis was present in 49.3% of the adolescents examined, the rest of the group was considered healthy. The IL-18 -607C and MMP-9 -1562T alleles were found in 58.9% and 8.3% of the healthy subjects, and in 62.2% and 15.0% of the patients with gingivitis, respectively. Although differences in allele frequencies were not significant for IL-18 variant, they were significant for MMP-9 polymorphism (p=0.01, p(corr) < 0.05). Furthermore, a highly significant association of the composite genotype (formed by the variants of the both genes) with gingivitis was found (p=0.004, p(corr) < 0.05).

CONCLUSIONS

The -1562 T allele of MMP-9 gene could have a role in gingivitis in adolescents. In addition, interaction of the MMP-9 and IL-18 genes could be considered a risk factor for the development of gingivitis in children.

Analysis of neutrophil-derived antimicrobial peptides in gingival crevicular fluid suggests importance of cathelicidin LL-37 in the innate immune response against periodontogenic bacteria

INTRODUCTION

During periodontitis, an innate immune response to bacterial challenge is primarily mediated by neutrophils. We compared neutrophilic content and the level of neutrophil-derived antimicrobial peptides in gingival crevicular fluid (GCF) in two clinical forms of severe periodontitis.

METHODS

GCF was collected from 14 patients with aggressive periodontitis, 17 patients with chronic periodontitis, and nine healthy subjects. Samples were analyzed for periodontopathogen load using real-time polymerase chain reactions. The amounts of myeloperoxidase and alpha-defensins (HNP1-3) were determined by enzyme-linked immunosorbent assay, and the level of cathelicidin (hCAP18/LL-37) was assayed by Western blot.

RESULTS

Myeloperoxidase concentration was not correlated with levels of LL-37 and HNP1-3 in samples from patients, compared to controls. The amount of HNP1-3 was twofold and fourfold higher in patients with aggressive and chronic periodontitis, respectively. Those with chronic disease had significantly elevated amounts of mature LL-37. The increased concentration of both peptides in chronic periodontitis correlated with the load of Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola.

CONCLUSION

The lack of a correlation between LL-37, HNP1-3, and myeloperoxidase content suggests that neutrophils are not the sole source of these bactericidal peptides in the GCF of patients with periodontitis; and that other cells contribute to their local production. The bacterial proteases of P. gingivalis, T. forsythia, and T. denticola might degrade hCAP18/LL-37, because the 11-kDa cathelicidin-derived fragment was present in GCF collected from pockets infected with these bacteria. Collectively, it appears that a local deficiency in LL-37 can be considered as a supporting factor in the pathogenesis of severe cases of periodontitis.