Destructive periodontal disease in adults 30 years of age and older in the United States, 1988-1994

[Update in family medicine: Periodontal disease]

About 85-94% of the Spanish adults older than 35 experience gum problems, and about 15-30% suffer from periodontitis, being severe in up to 5-11% of them. Unlike other inflammatory conditions, periodontal disease rarely causes discomfort, or limits life or causes functional limitations until its advanced stages, when clinical signs and symptoms arise (gingival recession, pathological teeth migration, or mobility). Lack of knowledge about the disease, together with the idea that tooth loss is linked to ageing, frequently results in a late diagnosis, requiring extensive treatments with a worse prognosis. At Primary Care level, there is series of drugs have been related to periodontal disease (anticonvulsants, immunosuppressive drugs, and calcium channel blockers) as secondary effects, which vary as regards their frequency and severity depending of the amount of accumulated plaque. Stress and depression have also been reported to alter the immune response and to increase the inflammatory response as well as periodontal susceptibility. Certain systemic conditions, such as diabetes mellitus, cardiovascular disorders, respiratory diseases, as well as low-weight pre-term birth, have also been linked to periodontitis.

The association between dental health and nutritional status in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) and periodontitis are chronic inflammatory systemic diseases with common risk factors (smoking and aging). In COPD, poor periodontal health could result in inadequate nutrition, potentially causing loss of muscle volume. The purpose of this case-control study was to examine our hypothesis that COPD patients have poorer periodontal health and poorer nutritional status than non-COPD patients. Periodontal status was assessed using bleeding on probing (BOP), pocket depth (PD), and plaque-control ratio (PCR). Nutritional status was assessed using body mass index, lean body mass, and serum albumin levels. The COPD group ( n = 60) had fewer remaining teeth, greater BOP, greater PD, and lower serum albumin levels compared with smokers without COPD ( n = 41) and nonsmokers ( n = 35; p < 0.001). COPD was an independent risk factor for poor periodontal health, demonstrated by fewer remaining teeth (relative risk (RR), 5.48; p = 0.0024), BOP (RR, 12.8; p = 0.0009), and having >30% of remaining teeth with a PD ≥ 4 mm (RR, 4.82; p = 0.011). A significant negative correlation existed between the number of teeth with a PD ≥ 4 mm and serum albumin level ( r² = 0.127; p = 0.013). We demonstrated that poor periodontal health was associated with hypoalbuminemia, suggesting poor nutritional status and inflammation in COPD.

Thrombin Activates Latent TGFβ1 via Integrin αvβ1 in Gingival Fibroblasts

Transforming growth factor β (TGFβ) regulates cell proliferation, differentiation, migration, apoptosis, and extracellular matrix production. It also plays a pivotal role in the pathogenesis of gingival overgrowth. Thrombin is a key player in tissue repair, remodeling, and fibrosis after an injury, and it exerts profibrotic effects by activating protease-activated receptors. Connective tissue growth factor (CTGF or CCN2) modulates cell adhesion, migration, proliferation, matrix production, and wound healing. It is overexpressed in many fibrotic disorders, including gingival overgrowth, and it is positively associated with the degree of fibrosis in gingival overgrowth. In human gingival fibroblasts, we previously found that TGFβ1 induced CCN2 protein synthesis through c-jun N-terminal kinase and Smad3 activation. Thrombin stimulates CCN2 synthesis through protease-activated receptor 1 and c-jun N-terminal kinase signaling. Curcumin inhibited TGFβ1- and thrombin-induced CCN2 synthesis. In this study, we demonstrated that thrombin and protease-activated receptor 1 agonist SFLLRN induced latent TGFβ1 activation and Smad3 phosphorylation in human gingival fibroblasts. Pretreatment with a TGFβ-neutralizing antibody, TGFβ type I receptor inhibitor SB431542, and Smad3 inhibitor SIS3 inhibited approximately 86%, 94%, and 100% of thrombin-induced CCN2 synthesis, respectively. Furthermore, blocking integrin subunits αv and β1 with antibodies effectively inhibited SFLLRN-induced Smad3 phosphorylation and CCN2 synthesis and increased activated TGFβ1 levels; however, similar effects were not observed for integrins αvβ3 and αvβ5. These results suggest that protease-activated receptor 1-induced CCN2 synthesis in human gingival fibroblasts is mediated through integrin αvβ1-induced latent TGFβ1 activation and subsequent TGFβ1 signaling. Moreover, curcumin dose dependently decreased thrombin-induced activated TGFβ1 levels. Curcumin-inhibited thrombin-induced CCN2 synthesis in human gingival fibroblasts is caused by the suppression of latent TGFβ1 activation.

The Periodontal Status and Associated Systemic Health Problems among an Elderly Population Attending the Outpatient Clinics of a Dental School

AIM

Periodontal diseases are associated with systemic health and health behaviors; the purpose of this study was to investigate periodontal health status and its association with systemic health and health behaviors in the elderly.

MATERIALS AND METHODS

Data was collected from 300 random Case Western Reserve University (CWRU) dental school patient charts, aged 65 or higher. A modified WHO form was used to collect the date on: periodontal conditions using the community periodontal index (CPI), demographics, systemic health and certain health behaviors. Community periodontal index collected data for six sextants. Descriptive tests and bivariate analytic tests, Chi-square test and computation of odds ratio, investigated any association between certain periodontal conditions and demographic as well as systemic health attributes.

RESULTS

In the study cohort, the average age was 73.7 ± 6.8 years. Moderate periodontitis (38.9%) was the most prevalent periodontal health condition, while severe periodontitis was the least prevalent periodontal health (6.1%). Nearly 30% of the cohort had healthy periodontium. Only insurance status was associated with healthy periodontium (p < 0.05).

CONCLUSION

Moderate periodontitis was the most prevalent among the studied subjects. A positive association was found with the insurance status of the subjects and the healthy periodontium. No association was found between periodontal disease and smoking, alcohol consumption, diabetes and cardiovascular disease.

Prevalence of chronic periodontitis in an obese population: a preliminary study

Background

Chronic periodontitis (CP) is a global public health issue. Studies have suggested CP could be linked to obesity due to their similar pathophysiological pathway. The aim of this study is to determine the prevalence of CP and to assess the predictors for CP among the obese Malaysian population.

Methods

This is a cross-sectional study on obese participants. Obesity is defined as an individual who has Body Mass Index (BMI) ≥27.5 kg/m². A convenience sampling method was used. A total of 165 paricipants were recruited. This study involved answering questionnaires, obtaining biometric and clinical measurements of Visible plaque index (VPI), Gingival bleeding index (GBI), Probing pocket depth (PPD) and Clinical attachment loss (CAL). Data analysis was carried out using SPSS statistical software (SPSS Inc., version 20, US).

Results

A total of 165 participants; 67 (40.6 %) males and 98 (59.4 %) females participated in the study. Mean age of the participants was 43.9 (±8.9). The prevalence of CP among the obese population was found to be 73.9 %. Out of this, 43 and 55 % were categorised as moderate and severe CP respectively. Around 64 % of participants had sites with CAL ≥4 mm and participants with sites with PPD ≥4 mm were reported to be 25 %. Around 83 % of the participants had sites with GBI ≥30 and 92 % of participants had sites with VPI ≥20 %. GBI and VPI were found to have significantly higher odds for CP.

Conclusion

Prevalence of CP was high among obese Malaysians. GBI and VPI were potential predictors for CP in this obese population.

Immunohistochemical localisation and effect of matrix metalloproteinases and their inhibitors on canine spontaneous periodontitis

Periodontitis is commonly observed in dogs. In human medicine, it is well documented that matrix metalloproteinases (MMPs) are involved in the destruction of the periodontium. Therefore, the aim of this prospective study was to investigate the impact of MMPs and their inhibitors, the TIMPs (tissue inhibitors of metalloproteinases), on canine periodontitis. The oral cavities of 57 dogs were examined clinically and radiologically. Gingival biopsies were obtained from the examined dogs and histologically analysed via haematoxylin and eosin stained sections. Immunohistological detection of MMP-2, MMP-3, MMP-8 and MMP-9 as well as TIMP-1 and TIMP-2 was performed by the avidin-biotin peroxidase complex technique. All sections were evaluated by light microscopy. Statistically significant positive correlations were detected between the histologically verified degree of inflammation and the expression of MMP-2, MMP-3, MMP-8 and MMP-9 as well as between changes in collagen fibre content and the occurrence of MMP-2, MMP-8 and MMP-9. Concerning TIMP-1 and TIMP-2, non-significant, generally negative correlations were observed. In summary, in canine periodontitis, an increased expression of the above mentioned MMPs and a tendentially decreased expression of TIMPs are present. In conclusion, in canine periodontitis, a MMP-TIMP imbalance is suggestive of contributing to the destruction of the periodontium.

Bias in estimating the cross-sectional smoking, alcohol, obesity and diabetes associations with moderate-severe periodontitis in the Atherosclerosis Risk in Communities study: comparison of full versus partial-mouth estimates

OBJECTIVE

To assess whether partial-mouth protocols (PRPs) result in biased estimates of the associations between smoking, alcohol, obesity and diabetes with periodontitis.

METHODS

Using a sample (n = 6129) of the 1996-1998 Atherosclerosis Risk in Communities study, we used measures of probing pocket depth and clinical attachment level to identify moderate-severe periodontitis. Adjusting for confounders, unconditional binary logistic regression estimated prevalence odds ratios (POR) and 95% confidence limits. Specifically, we compared POR for smoking, alcohol, obesity and diabetes with periodontitis derived from full-mouth to those derived from 4-PRPs (Ramfjörd, National Health and Nutrition Examination survey-III, modified-NHANES-IV and 42-site-Random-site selection-method). Finally, we conducted a simple sensitivity analysis of periodontitis misclassification by changing the case definition threshold for each PRP.

RESULTS

In comparison to full-mouth PORs, PRP PORs were biased in terms of magnitude and direction. Holding the full-mouth case definition at moderate-severe periodontitis and setting it at mild-moderate-severe for the PRPs did not consistently produce POR estimates that were either biased towards or away from the null in comparison to full-mouth estimates.

CONCLUSIONS

Partial-mouth protocols result in misclassification of periodontitis and may bias epidemiologic measures of association. The magnitude and direction of this bias depends on choice of PRP and case definition threshold used.

Prevalence of periodontitis in an adult population from an urban area in North Italy: findings from a cross-sectional population-based epidemiological survey

AIM

There is a paucity of up-to-date data regarding prevalence and risk indicators of periodontitis in Italy. Therefore, the aim of this study was to evaluate the prevalence of periodontitis and its risk indicators among adults from an urban area in North Italy.

MATERIAL AND METHODS

This cross-sectional survey used a stratified two-stage probability sampling method to draw a representative sample of the adult population of the city of Turin. About 1600 individuals, 20-75 years old, were randomly selected and 736 subjects agreed to participate (47% of the sampled subjects). Clinical parameters were assessed using a full-mouth protocol. Logistic models were applied to assess associations between periodontitis and its putative risk indicators. Age was included as restricted cubic spline.

RESULTS

Based on CDC/AAP case definition, the prevalence estimates of severe and moderate periodontitis were 34.94% (95% CI: 31.23-38.74) and 40.78% (95% CI: 36.89-44.79). The probability of periodontitis increased in smokers (adjusted OR 2.06, 95% IC: 1.26-3.37, p = 0.004) and with age but leveled off in the 50+ year-old group (p < 0.001).

CONCLUSION

Periodontitis was highly prevalent in the Turin population. The present data will enable development of appropriate public health programs and allocation of resources.

Development and characterization of novel ZnO-loaded electrospun membranes for periodontal regeneration

OBJECTIVES

This study reports on the synthesis, materials characterization, antimicrobial capacity, and cytocompatibility of novel ZnO-loaded membranes for guided tissue/bone regeneration (GTR/GBR).

METHODS

Poly(ɛ-caprolactone) (PCL) and PCL/gelatin (PCL/GEL) were dissolved in hexafluoropropanol and loaded with ZnO at distinct concentrations: 0 (control), 5, 15, and 30wt.%. Electrospinning was performed using optimized parameters and the fibers were characterized via scanning and transmission electron microscopies (SEM/TEM), energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), contact angle (CA), mechanical testing, antimicrobial activity against periodontopathogens, and cytotoxicity test using human dental pulp stem cells (hDPSCs). Data were analyzed using ANOVA and Tukey (α=5%).

RESULTS

ZnO nanoparticles were successfully incorporated into the overall submicron fibers, which showed fairly good morphology and microstructure. Upon ZnO nanoparticles' incorporation, the PCL and PCL/GEL fibers became thicker and thinner, respectively. All GEL-containing membranes showed lower CA than the PCL-based membranes, which were highly hydrophobic. Overall, the mechanical properties of the membranes were reduced upon ZnO incorporation, except for PCL-based membranes containing ZnO at the 30wt.% concentration. The presence of GEL enhanced the stretching ability of membranes under wet conditions. All ZnO-containing membranes displayed antibacterial activity against the bacteria tested, which was generally more pronounced with increased ZnO content. All membranes synthesized in this study demonstrated satisfactory cytocompatibility, although the presence of 30wt.% ZnO led to decreased viability.

SIGNIFICANCE

Collectively, this study suggests that PCL- and PCL/GEL-based membranes containing a low content of ZnO nanoparticles can potentially function as a biologically safe antimicrobial GTR/GBR membrane.

Standards for reporting chronic periodontitis prevalence and severity in epidemiologic studies: Proposed standards from the Joint EU/USA Periodontal Epidemiology Working Group

Periodontal diseases are common and their prevalence varies in different populations. However, prevalence estimates are influenced by the methodology used, including measurement techniques, case definitions, and periodontal examination protocols, as well as differences in oral health status. As a consequence, comparisons between populations are severely hampered and inferences regarding the global variation in prevalence can hardly be drawn. To overcome these limitations, the authors suggest standardized principles for the reporting of the prevalence and severity of periodontal diseases in future epidemiological studies. These principles include the comprehensive reporting of the study design, the recording protocol, and specific subject-related and oral data. Further, a range of periodontal data should be reported in the total population and within specific age groups. Periodontal data include the prevalence and extent of clinical attachment loss (CAL) and probing depth (PD) on site and tooth level according to specific thresholds, mean CAL/PD, the CDC/AAP case definition, and bleeding on probing. Consistent implementation of these standards in future studies will ensure improved reporting quality, permit meaningful comparisons of the prevalence of periodontal diseases across populations, and provide better insights into the determinants of such variation.

Update on Prevalence of Periodontitis in Adults in the United States: NHANES 2009 to 2012

BACKGROUND

This report describes prevalence, severity, and extent of periodontitis in the US adult population using combined data from the 2009 to 2010 and 2011 to 2012 cycles of the National Health and Nutrition Examination Survey (NHANES).

METHODS

Estimates were derived for dentate adults, aged ≥30 years, from the US civilian non-institutionalized population. Periodontitis was defined by combinations of clinical attachment loss (AL) and periodontal probing depth (PD) from six sites per tooth on all teeth, except third molars, using standard surveillance case definitions. For the first time in NHANES history, sufficient numbers of non-Hispanic Asians were sampled in 2011 to 2012 to provide reliable estimates of their periodontitis prevalence.

RESULTS

In 2009 to 2012, 46% of US adults, representing 64.7 million people, had periodontitis, with 8.9% having severe periodontitis. Overall, 3.8% of all periodontal sites (10.6% of all teeth) had PD ≥4 mm, and 19.3% of sites (37.4% teeth) had AL ≥3 mm. Periodontitis prevalence was positively associated with increasing age and was higher among males. Periodontitis prevalence was highest in Hispanics (63.5%) and non-Hispanic blacks (59.1%), followed by non-Hispanic Asian Americans (50.0%), and lowest in non-Hispanic whites (40.8%). Prevalence varied two-fold between the lowest and highest levels of socioeconomic status, whether defined by poverty or education.

CONCLUSIONS

This study confirms a high prevalence of periodontitis in US adults aged ≥30 years, with almost fifty-percent affected. The prevalence was greater in non-Hispanic Asians than non-Hispanic whites, although lower than other minorities. The distribution provides valuable information for population-based action to prevent or manage periodontitis in US adults.

Do you kiss your mother with that mouth? An authentic large-scale undergraduate research experience in mapping the human oral microbiome

Clinical microbiology testing is crucial for the diagnosis and treatment of community and hospital-acquired infections. Laboratory scientists need to utilize technical and problem-solving skills to select from a wide array of microbial identification techniques. The inquiry-driven laboratory training required to prepare microbiology graduates for this professional environment can be difficult to replicate within undergraduate curricula, especially in courses that accommodate large student cohorts. We aimed to improve undergraduate scientific training by engaging hundreds of introductory microbiology students in an Authentic Large-Scale Undergraduate Research Experience (ALURE). The ALURE aimed to characterize the microorganisms that reside in the healthy human oral cavity-the oral microbiome-by analyzing hundreds of samples obtained from student volunteers within the course. Students were able to choose from selective and differential culture media, Gram-staining, microscopy, as well as polymerase chain reaction (PCR) and 16S rRNA gene sequencing techniques, in order to collect, analyze, and interpret novel data to determine the collective oral microbiome of the student cohort. Pre- and postsurvey analysis of student learning gains across two iterations of the course (2012-2013) revealed significantly higher student confidence in laboratory skills following the completion of the ALURE (p < 0.05 using the Mann-Whitney U-test). Learning objectives on effective scientific communication were also met through effective student performance in laboratory reports describing the research outcomes of the project. The integration of undergraduate research in clinical microbiology has the capacity to deliver authentic research experiences and improve scientific training for large cohorts of undergraduate students.

Dysbiosis and alterations in predicted functions of the subgingival microbiome in chronic periodontitis

Chronic periodontitis is an inflammatory disease of the periodontium affecting nearly 65 million adults in the United States. Changes in subgingival microbiota have long been associated with chronic periodontitis. Recent culture-independent molecular studies have revealed the immense richness and complexity of oral microbial communities. However, data sets across studies have not been directly compared, and whether the observed microbial variations are consistent across different studies is not known. Here, we used 16S rRNA sequencing to survey the subgingival microbiota in 25 subjects with chronic periodontal disease and 25 healthy controls and compared our data sets with those of three previously reported microbiome studies. Consistent with data from previous studies, our results demonstrate a significantly altered microbial community structure with decreased heterogeneity in periodontal disease. Comparison with data from three previously reported studies revealed that subgingival microbiota clustered by study. However, differences between periodontal health and disease were larger than the technical variations across studies. Using a prediction score and applying five different distance metrics, we observed two predominant clusters. One cluster was driven by Fusobacterium and Porphyromonas and was associated with clinically apparent periodontitis, and the second cluster was dominated by Rothia and Streptococcus in the majority of healthy sites. The predicted functional capabilities of the periodontitis microbiome were significantly altered. Genes involved in bacterial motility, energy metabolism, and lipopolysaccharide biosynthesis were overrepresented in periodontal disease, whereas genes associated with transporters, the phosphotransferase system, transcription factors, amino acid biosynthesis, and glycolysis/gluconeogenesis were enriched in healthy controls. These results demonstrate significant alterations in microbial composition and function in periodontitis and suggest genes and metabolic pathways associated with periodontal disease.

A 4-year prospective study of the progression of periodontal disease in a rural Chinese population

OBJECTIVES

The natural progression of periodontitis in the Chinese population is not well researched. We investigated the progression of periodontal disease over 4 years in 15-44-year-old Chinese villagers with no access to regular dental care.

METHODS

In 1992, 486 villagers were enrolled, and in 1996, 413 villagers were re-examined. Probing depth (PD) and clinical attachment level (CAL) were examined at six sites per tooth. Sites with ΔCAL ≥3 mm were defined as active sites. Cross-sectional and longitudinal analyses were performed using means and percentile plots.

RESULTS

The mean CAL increased by 0.26 mm over 4 years. The incidence of periodontitis (at least one site with CAL ≥3 mm) was 8%. The incidence of periodontitis among those with no periodontal disease at baseline was 44.9%. Seventy-eight percent of the subjects had at least one active site. In the 15-24-year group, 244 of 401 active sites had gingival recession, while only 51 active sites had both gingival recession and deeper pockets. In the 25-34-year and 35-44-year groups, almost one-third of the active sites (329/1087) and more than one-third of the active sites (580/1312) respectively had a combination of gingival recession and deeper pockets.

CONCLUSIONS

In this study, we demonstrated that in Chinese population without regular dental care, both the initiation of periodontitis and progression of previously existed periodontitis contributed to the natural progression of periodontitis and periodontal pocketing played a greater role with age increasing.

CLINICAL SIGNIFICANCE

This rare study reports the natural progression of periodontal disease in a group of Chinese villagers (15-44 years) with virtually no access to regular dental care.

Effects of periodontal therapy on metabolic control in patients with type 2 diabetes mellitus and periodontal disease: a meta-analysis

Epidemiologic studies have reported increased incidence, prevalence and acuity of periodontitis in adults with diabetes and some have also suggested that treating periodontal disease may improve glycemic control in diabetic patients. This meta-analysis was conducted to evaluate the effects of different periodontal therapies on metabolic control in patients with type 2 diabetes mellitus (T2DM) and periodontal disease. We searched the Medline, EMBASE and Cochrane Library (Central) databases up to January 2014 for relevant studies pertaining to periodontal treatments and glycemic control in adults with T2DM. The search terms were periodontal treatment/periodontal therapy, diabetes/diabetes mellitus, periodontitis/periodontal and glycemic control. The primary outcome measure taken from the included studies was glycated hemoglobin (HbA1c). We compared differences in patients' pre- and post-intervention HbA1c results between a treatment group receiving scaling and root planing (SRP) combined with administration of oral doxycycline (n=71) and controls receiving SRP alone or SRP plus placebo (n=72). Meta-analysis was performed using Comprehensive Meta Analysis software. Nineteen randomized controlled trials (RCTs) were identified. Four trials involving a total of 143 patients with T2DM and periodontal disease were determined to be eligible for analysis. Data of 1 study were not retained for meta-analysis because HbA1c results were recorded as median with IQR. Meta-analysis of the included 3 studies revealed no significant differences in HbA1c results between the periodontal treatment group (n=71) and control group (n=72) (HbA1c SMD=-0.238, 95% CI=-0.616 to 0.140; P=0.217). Systemic doxycycline added to SRP does not significantly improve metabolic control in patients with T2DM and chronic periodontitis. Current evidence is insufficient to support a significant association between periodontal therapy and metabolic control in this patient population. However, evidence suggests that periodontal therapy itself improves metabolic control and reinforces that T2DM is a risk factor for periodontitis.

Polymorphisms in Glutathione S-Transferase M1, T1, and P1 in Patients with Chronic Periodontitis: A Pilot Study

Background. Although the direct cause of chronic periodontitis is bacterial infection, the progression of this disease depends on genetic and environmental factors, and smoking is a known risk factor in the development and severity of the disease. An individual's susceptibility may be influenced by polymorphisms in the glutathione S-transferase genes. These genes encode enzymes that metabolize xenobiotic compounds. The aim of this study was to determine the frequency of GSTM1, GSTT1, and GSTP1 polymorphisms in Mexicans with chronic periodontitis. Methods. 60 Mexicans with chronic periodontitis (30 smokers and 30 nonsmokers) were studied. A peripheral blood sample was taken for subsequent DNA extraction. The genetic material was PCR-amplified followed by restriction fragment length polymorphism with the aim of identifying GST polymorphisms. Results. Polymorphisms in the GSTT1 and GSTP1 genes were not significantly different between the smokers and nonsmokers. However, there were significant differences (P = 0.05) between groups in polymorphisms in the GSTM1 gene. The patients with chronic periodontitis have a higher frequency of null and mutant polymorphisms in GSTM1, GSTT1, and GSTP1 compared with historical data from a healthy Mexican population. Conclusions. The presence of these polymorphisms may be a risk factor for the development of chronic periodontitis.

Cellular composition of long-standing gingivitis and periodontitis lesions

BACKGROUND AND OBJECTIVE

Insufficient information on the cellular composition of long-standing gingivitis lesions without signs of attachment loss makes an understanding of differences in cellular composition between "destructive" and "nondestructive" periodontal lesions difficult. The aim of the current study was to analyze differences in cell characteristics between lesions representing long-standing gingivitis and severe periodontitis.

MATERIAL AND METHODS

Two groups of patients were recruited. One group consisted of 36 patients, 33-67 years of age, with severe generalized periodontitis (periodontitis group). The second group consisted of 28 patients, 41-70 years of age, with overt signs of gingival inflammation but no attachment loss (gingivitis group). From each patient a gingival biopsy was obtained from one selected diseased site and prepared for immunohistochemical analysis.

RESULTS

Periodontitis lesions were twice as large and contained significantly larger proportions, numbers and densities of cells positive for CD138 (plasma cells) and CD68 (macrophages) than did gingivitis lesions. The proportion of B cells that expressed the additional CD5 marker (B-1a cells) was significantly larger in periodontitis lesions than in gingivitis lesions. The densities of T cells and B cells did not differ between periodontitis lesions and gingivitis lesions. T cells were not the dominating cell type in gingivitis lesions, as B cells together with their subset plasma cells comprised a larger number and proportion than T cells.

CONCLUSION

Periodontitis lesions at teeth with advanced attachment and bone loss exhibit quantitative and qualitative differences in relation to gingivitis lesions at teeth with no attachment and bone loss. It is suggested that the large number and high density of plasma cells are the hallmarks of advanced periodontitis lesions and the most conspicuous difference in relation to long-standing gingivitis lesions.

Dental prophylaxis decreases the risk of esophageal cancer in males; a nationwide population-based study in Taiwan

BACKGROUND

Periodontal disease (PD) is one of the most common chronic inflammatory diseases. Esophageal cancer (EC) is also a common cause of death due to cancer among males. Systemic inflammatory processes have been shown to increase the risk of cancer. We conducted a retrospective cohort study to investigate the association between PD and EC.

METHODS

A total of 718,409 subjects were recruited from the Taiwan National Health Insurance Research Database (NHIRD) and followed from January 1, 2000 to December 31, 2010. Of these, 519,831 subjects were diagnosed with PD and were grouped according to the most advanced treatment they received: dental prophylaxis, intensive treatment, or no treatment. The IRs of EC were compared among groups.

RESULTS

A total of 682 patients developed EC, resulting in an overall IR of 0.11 case-number per 1000 person-years (‰/y). The dental prophylaxis group had a significantly lower IR of EC (0.06‰/y) than other groups (p<0.001). Multivariable Cox regression analysis further revealed that male subjects [hazard ratio (HR) = 10.04, 95% confidence interval (CI)  = 7.58-13.30], as well as a history of esophageal ulcers (HR = 7.10, 95% CI = 5.03-10.01), alcohol abuse (HR = 5.46, 95% CI = 2.26-13.18), or esophageal reflux (HR = 1.86, 95% CI = 1.02-3.52), were factors associated with a higher risk of EC. And the dental prophylaxis group showed a significantly lower risk for EC (HR = 0.53, 95% CI = 0.44-0.65). Further subgroup analysis showed that the dental prophylaxis group among males had a significant lower risk (HR = 0.54, 95% CI = 0.44-0.66) for EC, while that of the females did not has statistically significant difference.

CONCLUSION

For this cohort, subjects received dental prophylaxis reduced the risk of EC compared to all PD and no PD groups among males.

A SEMI-PARAMETRIC BAYESIAN MODEL OF INTER- AND INTRA-EXAMINER AGREEMENT FOR PERIODONTAL PROBING DEPTH

Periodontal probing depth is a measure of periodontitis severity. We develop a Bayesian hierarchical model linking true pocket depth to both observed and recorded values of periodontal probing depth, while permitting correlation among measures obtained from the same mouth and between duplicate examiners' measures obtained at the same periodontal site. Periodontal site-specific examiner effects are modeled as arising from a Dirichlet process mixture, facilitating identification of classes of sites that are measured with similar bias. Using simulated data, we demonstrate the model's ability to recover examiner site-specific bias and variance heterogeneity and to provide cluster-adjusted point and interval agreement estimates. We conclude with an analysis of data from a probing depth calibration training exercise.

A spatial augmented beta regression model for periodontal proportion data

Clinical dental research generates large amounts of data with a potentially complex correlation structure from measurements recorded at several sites throughout the mouth. Clinical attachment level (CAL) is one such measure popularly used to assess the periodontal disease (PD) status. We model the proportion of sites for each tooth-type (i.e., incisor, canine, pre-molar and molar) per subject that exhibit moderate to severe PD. Disease free and highly diseased tooth-sites cause these proportion responses to lie in the closed interval [0, 1]. In addition, PD may be spatially referenced, i.e., the disease status of a site is influenced by its neighbours. While beta regression can assess the covariate-response relationship for proportion data, its support in the interval (0, 1) impairs its ability to account for the observed proportions at zero and one. In contrast to ad hoc transformations that confine responses to (0, 1), we develop a framework that augments the beta density with non-zero masses at zero and one while also controlling for spatial referencing. Our approach is Bayesian and is computationally amenable to available software. A simulation study evaluates estimation of regression effects in scenarios of varying sample size, degree of spatial dependence and response transformations. Application to real PD data provide insights into assessing covariate effects on proportion responses.

Periodontal disease and Helicobacter pylori infection: a community-based study using serology and rapid urease test

AIMS

The aims of the present study were to assess the prevalence of periodontal disease and Helicobacter pylori (H. pylori) infection and their associations within a predefined Indian population.

METHODS

A community-based cross-sectional study of 500 selected individuals using a questionnaire, oral examination, rapid urease testing of dental plaque, and serological examination for immunoglobulin G antibody to H. pylori was carried out.

RESULTS

Periodontal disease and H. pylori infection were prevalent in more than 50% of the population. Age, smoking, and diabetic status of the individuals were risk factors for periodontal disease after multivariate analysis, and a lack of proper sewage and waste disposal facilities were found to increase the risk of H. pylori infection. Although there was no association between periodontal disease and H. pylori seropositivity in the community, a highly-significant association was found between periodontal disease and colonization of H. pylori in dental plaque.

CONCLUSIONS

Because periodontal disease is associated with the increased colonization of H. pylori, new treatment modalities, such as plaque control measures, should be employed for the complete management of H. pylori-associated gastric disease.

Acute myocardial infarct size is related to periodontitis extent and severity

Cardiovascular disease has been associated with 40% of deaths in high-income countries and 28% in lower-income countries. The relationship between periodontitis and acute myocardial infarction is well documented, but it has not been established whether the extent and severity of periodontitis influence the infarct size. This cross-sectional and analytic study was designed to investigate the association of chronic periodontitis extent and severity with acute myocardial infarct size as indicated by serum cardiac troponin I and myoglobin levels. Sociodemographic, periodontal, cardiologic, and hematologic variables were gathered in 112 consecutive patients with myocardial infarction. The extent (Arbes Index) and severity (Periodontal Inflammatory Severity Index) of the chronic periodontitis were significantly associated with troponin I levels after controlling for sociodemographic and clinical confounders (change in R (2) = .041, p < .02, and R (2) = .031, p = .04). However, only the extent index accounted for levels of myoglobin (change in R (2) = .030, p < .05), total leukocytes (change in R (2) = .041 p < .02), and neutrophils (change in R (2) = .059, p < .01). Mediated regression analysis showed that leukocytes and neutrophils may underlie these observed relationships of chronic periodontitis with troponin I and myoglobin. To our knowledge, this study contributes the first research data demonstrating that the extent and severity of periodontitis is positively associated with acute myocardial infarct size as measured by serum troponin I and myoglobin levels.

Establishing and managing a periodontal biobank for research: the sharing of experience

Periodontal bio-repositories, which allow banking of clinically validated human data and biological samples, provide an opportunity to derive biomarkers for periodontal diagnosis, prognosis and therapeutic activities which are expected to improve patient management. This article presents the establishing of the Malaysian Periodontal Database and Biobank System (MPDBS) which was initiated in 2011 with the aim to facilitate periodontal research. Partnerships were established with collaborating centres. Policies on specimen access, authorship and acknowledgement policies were agreed upon by all participating centres before the initiation of the periodontal biobank. Ethical approval for the collection of samples and data were obtained from institutional ethics review boards. A broad-based approach for informed consent was used, which covered areas related to quality of life impacts, genetics and molecular aspects of periodontal disease. Sample collection and processing was performed using a standardized protocol. Biobanking resources such as equipment and freezers were shared with the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). In the development of the MPDBS, challenges that were previously faced by the MOCDTBS were considered. Future challenges in terms of ethical and legal issues will be faced when international collaborations necessitate the transportation of specimens across borders.

Sex differences in inflammatory and apoptotic signaling molecules in normal and diseased human gingiva

BACKGROUND

The purpose of this study is to determine whether sex dimorphism exists in the expression of inflammatory and apoptotic mediators in gingiva obtained from normal and diseased sites of periodontal disease.

METHODS

Gingival papillae were obtained from individuals (56 males and 62 females) who required extraction of adjacent teeth. Gingival samples were grouped by adjacent sulcus depth: 1 to 3 mm (normal), 3 mm with bleeding on probing (slight disease), 3 to 6 mm (moderate disease), and >6 mm (severe disease). The tissue concentrations of cysteine-requiring aspartate-directed protease 3 (caspase-3), interleukin-2, tumor necrosis factor-related apoptosis-inducing ligand, Fas ligand, p38α mitogen-activated protein kinase, extracellular signal-related kinase 1/2, and survivin were determined by enzyme-linked immunosorbent assay. These mediator concentrations, age of donor, sex of donor, and gingival sulcular depth were the outcome variables. Data were compared by factorial analysis of variance, post hoc Tukey, and Pearson correlation test. P <0.05 was used to indicate significant differences among the outcome variables.

RESULTS

The mean gingival sulcular depth was significantly greater in male than in female groups (P <0.05). The majority of the tested mediators were significantly correlated with both sex and sulcular depth and with caspase-3 (P <0.05). The concentration of caspase-3 in female gingiva at all diseased sites was significantly greater than in gingiva derived from male sites (P <0.05).

CONCLUSIONS

These data suggest sex dimorphism in the presence of gingival apoptosis at sites of periodontal disease, with females having the highest incidence of apoptosis. Because apoptosis clears inflammatory cells and promotes healing, this phenomenon could provide a mechanism for sex dimorphism for the incidence of periodontal disease.

Accuracy of self-reported periodontal disease in the Women's Health Initiative Observational Study

BACKGROUND

This study examines the accuracy of self-reported periodontal disease in a cohort of older females.

METHODS

The study comprised 972 postmenopausal females aged 53 to 83 years who completed baseline (1997 to 2001) and follow-up (2002 to 2006) whole-mouth oral examinations. Examinations included: 1) probing depth, 2) clinical attachment level, and 3) oral radiographs for alveolar crestal height in a study ancillary to the Women's Health Initiative Observational Study (WHI-OS) conducted in Buffalo, New York, called the OsteoPerio study. Participants also self-reported any history of diagnosis of periodontal/gum disease on a WHI-OS study-wide questionnaire administered during the time interval between the two OsteoPerio examinations.

RESULTS

Participants reporting diagnosis of periodontal/gum disease on the WHI-OS questionnaire (n = 259; 26.6%) had worse oral hygiene habits, periodontal disease risk factors, and clinical periodontal measures compared with those not reporting periodontal/gum disease. Frequency of reported periodontal/gum disease was 13.5%, 24.7%, and 56.2% across OsteoPerio baseline examination categories of none/mild, moderate, and severe periodontal disease, respectively (trend: P <0.001), defined by criteria of the Centers for Disease Control and Prevention/American Academy of Periodontology (CDC/AAP). Sensitivity, specificity, and positive and negative predictive values for reported periodontal disease status were 56.2%, 78.8%, 32.8%, and 90.7%, respectively, when CDC/AAP-defined severe periodontal disease at baseline was the criterion measure (prevalence of 15%) and were 76.0%, 77.4%, 22.0%, and 97.4%, respectively, when tooth loss to periodontitis (prevalence of 7%) was the criterion.

CONCLUSION

A simple question for self-reported periodontal disease characterizes periodontal disease prevalence with moderate accuracy in postmenopausal females who regularly visit their dentist, particularly in those with more severe disease.

Association between harmful alcohol use and periodontal status according to gender and smoking

Background

the aim of this study is to assess the association of harmful alcohol use based on the alcohol use disorders identification test (AUDIT) score with periodontal status according to gender and smoking in a representative sample of Korean adults.

Methods

This study analyzed 5,291 participants older than 19 years whose data of harmful alcohol use and periodontal status were available. Harmful alcohol use was defined by the WHO guidelines for the administration of AUDIT. The periodontal status was assessed by the Community Periodontal Index (CPI). Multivariate logistic regression analysis was performed with adjustment for socio-demographic variables, oral and general health behavior, oral health status and systemic conditions. All analyses considered a complex sampling design, and multivariate analysis was also performed in the subgroups.

Results

Multivariate logistic regression analysis revealed a marginal association between harmful alcohol use and higher CPI in the total sample. The adjusted odds ratio (OR) of harmful alcohol use was 1.16 (0.97 to 1.38) for higher CPI. Higher CPI was significantly associated with harmful alcohol use in men (OR: 1.28; 95% CI: 1.03-1.60) and non-smokers (OR: 1.29; 95% CI: 1.06-1.57).

Conclusion

Periodontal status is significantly associated with harmful alcohol use in men and non-smokers in a representative sample of Korean adults.

Macrophage inflammatory protein-1α shows predictive value as a risk marker for subjects and sites vulnerable to bone loss in a longitudinal model of aggressive periodontitis

Improved diagnostics remains a fundamental goal of biomedical research. This study was designed to assess cytokine biomarkers that could predict bone loss (BL) in localized aggressive periodontitis. 2,058 adolescents were screened. Two groups of 50 periodontally healthy adolescents were enrolled in the longitudinal study. One group had Aggregatibacter actinomycetemcomitans (Aa), the putative pathogen, while the matched cohort did not. Cytokine levels were assessed in saliva and gingival crevicular fluid (GCF). Participants were sampled, examined, and radiographed every 6 months for 2-3 years. Disease was defined as radiographic evidence of BL. Saliva and GCF was collected at each visit, frozen, and then tested retrospectively after detection of BL. Sixteen subjects with Aa developed BL. Saliva from Aa-positive and Aa-negative healthy subjects was compared to subjects who developed BL. GCF was collected from 16 subjects with BL and from another 38 subjects who remained healthy. GCF from BL sites in the 16 subjects was compared to healthy sites in these same subjects and to healthy sites in subjects who remained healthy. Results showed that cytokines in saliva associated with acute inflammation were elevated in subjects who developed BL (i.e., MIP-1α MIP-1β IL-α, IL-1β and IL-8; p<0.01). MIP-1α was elevated 13-fold, 6 months prior to BL. When MIP-1α levels were set at 40 pg/ml, 98% of healthy sites were below that level (Specificity); whereas, 93% of sites with BL were higher (Sensitivity), with comparable Predictive Values of 98%; p<0.0001; 95% C.I. = 42.5-52.7). MIP-1α consistently showed elevated levels as a biomarker for BL in both saliva and GCF, 6 months prior to BL. MIP-1α continues to demonstrate its strong candidacy as a diagnostic biomarker for both subject and site vulnerability to BL.

The periodontal pathogen Porphyromonas gingivalis induces expression of transposases and cell death of Streptococcus mitis in a biofilm model

Oral microbial communities are extremely complex biofilms with high numbers of bacterial species interacting with each other (and the host) to maintain homeostasis of the system. Disturbance in the oral microbiome homeostasis can lead to either caries or periodontitis, two of the most common human diseases. Periodontitis is a polymicrobial disease caused by the coordinated action of a complex microbial community, which results in inflammation of tissues that support the teeth. It is the most common cause of tooth loss among adults in the United States, and recent studies have suggested that it may increase the risk for systemic conditions such as cardiovascular diseases. In a recent series of papers, Hajishengallis and coworkers proposed the idea of the "keystone-pathogen" where low-abundance microbial pathogens (Porphyromonas gingivalis) can orchestrate inflammatory disease by turning a benign microbial community into a dysbiotic one. The exact mechanisms by which these pathogens reorganize the healthy oral microbiome are still unknown. In the present manuscript, we present results demonstrating that P. gingivalis induces S. mitis death and DNA fragmentation in an in vitro biofilm system. Moreover, we report here the induction of expression of multiple transposases in a Streptococcus mitis biofilm when the periodontopathogen P. gingivalis is present. Based on these results, we hypothesize that P. gingivalis induces S. mitis cell death by an unknown mechanism, shaping the oral microbiome to its advantage.

Effects of periodontal treatment on lung function and exacerbation frequency in patients with chronic obstructive pulmonary disease and chronic periodontitis: a 2-year pilot randomized controlled trial

AIM

To evaluate the direct effects of periodontal therapy in Chronic Obstructive Pulmonary Disease (COPD) patients with chronic periodontitis (CP).

MATERIALS AND METHODS

In a pilot randomized controlled trial, 60 COPD patients with CP were randomly assigned to receive scaling and root planing (SRP) treatment, supragingival scaling treatment, or oral hygiene instructions only with no periodontal treatment. We evaluated their periodontal indexes, respiratory function, and COPD exacerbations at baseline, 6 months, 1, and 2 years.

RESULTS

Compared with the control group, measurements of periodontal indexes were significantly improved in patients in two treatment groups at 6-month, 1-year, and 2-year follow-up (all p < 0.05). Overall, the means of forced expiratory volume in the first second/forced vital capacity (FEV1/FVC) and FEV1 were significantly higher in the two therapy groups compared with the control group during the follow-up (p < 0.05). In addition, the frequencies of COPD exacerbation were significantly lower in the two therapy groups than in the control group at 2-year follow-up (p < 0.05).

CONCLUSIONS

Our preliminary results from this pilot trial suggest that periodontal therapy in COPD patients with CP may improve lung function and decrease the frequency of COPD exacerbation.

Lessons learned and unlearned in periodontal microbiology

Periodontal diseases are initiated by bacterial species living in polymicrobial biofilms at or below the gingival margin and progress largely as a result of the inflammation elicited by specific subgingival species. In the past few decades, efforts to understand the periodontal microbiota have led to an exponential increase in information about biofilms associated with periodontal health and disease. In fact, the oral microbiota is one of the best-characterized microbiomes that colonize the human body. Despite this increased knowledge, one has to ask if our fundamental concepts of the etiology and pathogenesis of periodontal diseases have really changed. In this article we will review how our comprehension of the structure and function of the subgingival microbiota has evolved over the years in search of lessons learned and unlearned in periodontal microbiology. More specifically, this review focuses on: (i) how the data obtained through molecular techniques have impacted our knowledge of the etiology of periodontal infections; (ii) the potential role of viruses in the etiopathogenesis of periodontal diseases; (iii) how concepts of microbial ecology have expanded our understanding of host-microbe interactions that might lead to periodontal diseases; (iv) the role of inflammation in the pathogenesis of periodontal diseases; and (v) the impact of these evolving concepts on therapeutic and preventive strategies to periodontal infections. We will conclude by reviewing how novel systems-biology approaches promise to unravel new details of the pathogenesis of periodontal diseases and hopefully lead to a better understanding of their mechanisms.

Periodontitis: a host-mediated disruption of microbial homeostasis. Unlearning learned concepts

New concepts evolve when existing ones fail to address known factors adequately or are invalidated by new evidence. For decades periodontitis has been considered to be caused by specific bacteria or groups of bacteria and, accordingly, treatment protocols have largely been based on anti-infective therapies. However, close inspection of current data leads one to question whether these bacteria are the cause or the result of periodontitis. Good evidence is emerging to suggest that it is indeed the host response to oral bacteria that leads to the tissue changes noted in gingivitis. These changes lead to an altered subgingival environment that favors the emergence of 'periodontal pathogens' and the subsequent development of periodontitis if the genetic and external environmental conditions are favorable for disease development. Thus, it seems that it is indeed the initial early host-inflammatory and immune responses occurring during the development of gingivitis, and not specific bacteria or their so-called virulence factors, which determine whether periodontitis develops and progresses. In this review we consider these concepts and their potential to change the way in which we view and manage the inflammatory periodontal diseases.

Genome-wide association study of periodontal health measured by probing depth in adults ages 18-49 years

The etiology of chronic periodontitis clearly includes a heritable component. Our purpose was to perform a small exploratory genome-wide association study in adults ages 18–49 years to nominate genes associated with periodontal disease−related phenotypes for future consideration. Full-mouth periodontal pocket depth probing was performed on participants (N = 673), with affected status defined as two or more sextants with probing depths of 5.5 mm or greater. Two variations of this phenotype that differed in how missing teeth were treated were used in analysis. More than 1.2 million genetic markers across the genome were genotyped or imputed and tested for genetic association. We identified ten suggestive loci (p-value ≤ 1E-5), including genes/loci that have been previously implicated in chronic periodontitis: LAMA2, HAS2, CDH2, ESR1, and the genomic region on chromosome 14q21-22 between SOS2 and NIN. Moreover, we nominated novel loci not previously implicated in chronic periodontitis or related pathways, including the regions 3p22 near OSBPL10 (a lipid receptor implicated in hyperlipidemia), 4p15 near HSP90AB2P (a heat shock pseudogene), 11p15 near GVINP1 (a GTPase pseudogene), 14q31 near SEL1L (an intracellular transporter), and 18q12 in FHOD3 (an actin cytoskeleton regulator). Replication of these results in additional samples is needed. This is one of the first research efforts to identify genetic polymorphisms associated with chronic periodontitis-related phenotypes by the genome-wide association study approach. Though small, efforts such this are needed in order to nominate novel genes and generate new hypotheses for exploration and testing in future studies.

Moving into a new era of periodontal genetic studies: relevance of large case-control samples using severe phenotypes for genome-wide association studies

Studies to elucidate the role of genetics as a risk factor for periodontal disease have gone through various phases. In the majority of cases, the initial 'hypothesis-dependent' candidate-gene polymorphism studies did not report valid genetic risk loci. Following a large-scale replication study, these initially positive results are believed to be caused by type 1 errors. However, susceptibility genes, such as CDKN2BAS (Cyclin Dependend KiNase 2B AntiSense RNA; alias ANRIL [ANtisense Rna In the Ink locus]), glycosyltransferase 6 domain containing 1 (GLT6D1) and cyclooxygenase 2 (COX2), have been reported as conclusive risk loci of periodontitis. The search for genetic risk factors accelerated with the advent of 'hypothesis-free' genome-wide association studies (GWAS). However, despite many different GWAS being performed for almost all human diseases, only three GWAS on periodontitis have been published - one reported genome-wide association of GLT6D1 with aggressive periodontitis (a severe phenotype of periodontitis), whereas the remaining two, which were performed on patients with chronic periodontitis, were not able to find significant associations. This review discusses the problems faced and the lessons learned from the search for genetic risk variants of periodontitis. Current and future strategies for identifying genetic variance in periodontitis, and the importance of planning a well-designed genetic study with large and sufficiently powered case-control samples of severe phenotypes, are also discussed.

Clinical factors and self-perceived oral health

Self-perceived oral health is affected not only by awareness of the clinical status but also by comparisons with people of a similar age. This study explored the relative contributions of clinical variables assessing caries, periodontal status, and prosthetic status to self-perceived oral health within two age groups. Data of 891 adults (35-44 yr of age) and 760 older people (65-74 yr of age) from the Fourth German Oral Health Study (DMS IV, 2005) were evaluated. Self-perceived oral health was obtained from questionnaires. Numbers of decayed, filled, and unreplaced teeth, mean attachment loss, bleeding on probing (BOP), the presence of a fixed denture, and the presence of a removable denture were assessed. Multinomial logistic regression models were developed for both age groups, separately, using stepwise methods. For adults, unreplaced teeth, filled teeth, decayed teeth, the presence of a removable denture, and mean attachment loss were added to the final model. For older people, the presence of a removable denture, unreplaced teeth, decayed teeth, mean attachment loss, filled teeth, and BOP were included in the final model. Awareness of the relative contributions of clinical variables to self-perceived oral health is important for obtaining a clearer understanding of patients' subjective and objective self-perceptions of oral health.