Development and External Validation of a Multivariable Prediction Model to Identify Nondiabetic Hyperglycemia and Undiagnosed Type 2 Diabetes: Diabetes Risk Assessment in Dentistry Score (DDS)

The aim of this study was to develop and externally validate a score for use in dental settings to identify those at risk of undiagnosed nondiabetic hyperglycemia (NDH) or type 2 diabetes (T2D). The Studies of Health in Pomerania (SHIP) project comprises 2 representative population-based cohort studies conducted in northeast Germany. SHIP-TREND-0, 2008 to 2012 (the development data set) had 3,339 eligible participants, with 329 having undiagnosed NDH or T2D. Missing data were replaced using multiple imputation. Potential covariates were selected for inclusion in the model using backward elimination. Heuristic shrinkage was used to reduce overfitting, and the final model was adjusted for optimism. We report the full model and a simplified paper-based point-score system. External validation of the model and score employed an independent data set comprising 2,359 participants with 357 events. Predictive performance, discrimination, calibration, and clinical utility were assessed. The final model included age, sex, body mass index, smoking status, first-degree relative with diabetes, presence of a dental prosthesis, presence of mobile teeth, history of periodontal treatment, and probing pocket depths ≥5 mm as well as prespecified interaction terms. In SHIP-TREND-0, the model area under the curve (AUC) was 0.72 (95% confidence interval [CI] 0.69, 0.75), calibration in the large was -0.025. The point score AUC was 0.69 (95% CI 0.65, 0.72), with sensitivity of 77.0 (95% CI 76.8, 77.2), specificity of 51.5 (95% CI 51.4, 51.7), negative predictive value of 94.5 (95% CI 94.5, 94.6), and positive predictive value of 17.0 (95% CI 17.0, 17.1). External validation of the point score gave an AUC of 0.69 (95% CI 0.66, 0.71), sensitivity of 79.2 (95% CI 79.0, 79.4), specificity of 49.9 (95% CI 49.8, 50.00), negative predictive value 91.5 (95% CI 91.5, 91.6), and positive predictive value of 25.9 (95% CI 25.8, 26.0). A validated prediction model involving dental variables can identify NDH or undiagnosed T2DM. Further studies are required to validate the model for different European populations.

Phenotype Harmonization in the GLIDE2 Oral Health Genomics Consortium

Genetic risk factors play important roles in the etiology of oral, dental, and craniofacial diseases. Identifying the relevant risk loci and understanding their molecular biology could highlight new prevention and management avenues. Our current understanding of oral health genomics suggests that dental caries and periodontitis are polygenic diseases, and very large sample sizes and informative phenotypic measures are required to discover signals and adequately map associations across the human genome. In this article, we introduce the second wave of the Gene-Lifestyle Interactions and Dental Endpoints consortium (GLIDE2) and discuss relevant data analytics challenges, opportunities, and applications. In this phase, the consortium comprises a diverse, multiethnic sample of over 700,000 participants from 21 studies contributing clinical data on dental caries experience and periodontitis. We outline the methodological challenges of combining data from heterogeneous populations, as well as the data reduction problem in resolving detailed clinical examination records into tractable phenotypes, and describe a strategy that addresses this. Specifically, we propose a 3-tiered phenotyping approach aimed at leveraging both the large sample size in the consortium and the detailed clinical information available in some studies, wherein binary, severity-encompassing, and "precision," data-driven clinical traits are employed. As an illustration of the use of data-driven traits across multiple cohorts, we present an application of dental caries experience data harmonization in 8 participating studies (N = 55,143) using previously developed permanent dentition tooth surface-level dental caries pattern traits. We demonstrate that these clinical patterns are transferable across multiple cohorts, have similar relative contributions within each study, and thus are prime targets for genetic interrogation in the expanded and diverse multiethnic sample of GLIDE2. We anticipate that results from GLIDE2 will decisively advance the knowledge base of mechanisms at play in oral, dental, and craniofacial health and disease and further catalyze international collaboration and data and resource sharing in genomics research.

Repeated exposure of the oral mucosa over 12 months with cold plasma is not carcinogenic in mice

Peri-implantitis may result in the loss of dental implants. Cold atmospheric pressure plasma (CAP) was suggested to promote re-osseointegration, decrease antimicrobial burden, and support wound healing. However, the long-term risk assessment of CAP treatment in the oral cavity has not been addressed. Treatment with two different CAP devices was compared against UV radiation, carcinogen administration, and untreated conditions over 12 months. Histological analysis of 406 animals revealed that repeated CAP exposure did not foster non-invasive lesions or squamous cell carcinoma (SCCs). Carcinogen administration promoted non-invasive lesions and SCCs. Molecular analysis by a qPCR screening of 144 transcripts revealed distinct inflammatory profiles associated with each treatment regimen. Interestingly, CAP treatment of carcinogen-challenged mucosa did not promote but instead left unchanged or reduced the proportion of non-invasive lesions and SCC formation. In conclusion, repeated CAP exposure of murine oral mucosa was well tolerated, and carcinogenic effects did not occur, motivating CAP applications in patients for dental and implant treatments in the future.

Ten-year trends in DMF-S and DMF-T in a northeast German adult population

OBJECTIVE

The aim of this study was to assess 10-year trends in coronal caries in adults aged 20-83 years using data from the two-representative population-based Studies of Health in Pomerania (SHIP-0/SHIP-Trend-0).

METHODS

Repeated cross-sectional data from 4,286 SHIP-0 and 3,913 SHIP-Trend-0 participants were analysed. Carious, filled and missing teeth/surfaces were recorded in a half-mouth design and the DMF-T/S scores and sound surfaces/teeth were calculated according to WHO criteria. Trends in DMF-T/S scores and its single components were presented stratified by age group and sex.

RESULTS

A statistically significant decline in coronal caries experience (DMF-T and DMF-S) in adults aged 20 to 83 years as well as for D-T/S components was observed. The proportion of edentulous participants was almost halved from 8.7% (SHIP-0) to 5.1% (SHIP-Trend-0), while the number of M-T declined from 4.4 to 3.5 revealing an overall clear shift to a higher retention rate of teeth. In younger adults (25-34 years) 3.8 more sound teeth (17.2 sound surfaces) were found in average in the mouth and in elderly (65-74 years) a clear shift from extracted to filled teeth was observed (M-T reduced by 5.4, while F-T increased by 4). Regarding sex differences, females had consistently on average higher MF-T/S values, but lower D-T/S values than males.

CONCLUSION

A clinically relevant drop in the severity of coronal caries experience in all adult age groups in Northeast Germany shows that not only reductions in caries experience in adolescence translated into adulthood but also later improvements led to long-term oral health.

Is Continuous Eruption Related to Periodontal Changes? A 16-Year Follow-up

The aims of this study were to 1) determine if continuous eruption occurs in the maxillary teeth, 2) assess the magnitude of the continuous eruption, and 3) evaluate the effects of continuous eruption on the different periodontal parameters by using data from the population-based cohort of the Study of Health in Pomerania (SHIP). The jaw casts of 140 participants from the baseline (SHIP-0) and 16-y follow-up (SHIP-3) were digitized as 3-dimensional models. Robust reference points were set to match the tooth eruption stage at SHIP-0 and SHIP-3. Reference points were set on the occlusal surface of the contralateral premolar and molar teeth, the palatal fossa of an incisor, and the rugae of the hard palate. Reference points were combined to represent 3 virtual occlusal planes. Continuous eruption was measured as the mean height difference between the 3 planes and rugae fix points at SHIP-0 and SHIP-3. Probing depth, clinical attachment levels, gingiva above the cementoenamel junction (gingival height), and number of missing teeth were clinically assessed in the maxilla. Changes in periodontal variables were regressed onto changes in continuous eruption after adjustment for age, sex, number of filled teeth, and education or tooth wear. Continuous tooth eruption >1 mm over the 16 y was found in 4 of 140 adults and averaged to 0.33 mm, equaling 0.021 mm/y. In the total sample, an increase in continuous eruption was significantly associated with decreases in mean gingival height (B = -0.34; 95% CI, -0.65 to -0.03). In a subsample of participants without tooth loss, continuous eruption was negatively associated with PD. This study confirmed that continuous eruption is clearly detectable and may contribute to lower gingival heights in the maxilla.

Periodontitis Is Related to Exercise Capacity: Two Cross-sectional Studies

Although a potential link between periodontitis and cardiorespiratory fitness might provide a reasonable explanation for effects of tooth-related alterations seen on cardiometabolic diseases, evidence is currently limited. Thus, we investigated the association between clinically assessed periodontitis and cardiopulmonary exercise testing (CPET). Data from 2 independent cross-sectional population-based studies (5-y follow-up of the Study of Health in Pomerania [SHIP-1; N = 1,639] and SHIP-Trend-0 [N = 2,439]) were analyzed. Participants received a half-mouth periodontal examination, and teeth were counted. CPET was based on symptom limited-exercise tests on a bicycle ergometer. Associations of periodontitis parameters with CPET parameters were analyzed by confounder-adjusted multivariable linear regression. In the total sample, mean pocket probing depth (PPD), mean clinical attachment levels, and number of teeth were consistently associated with peak oxygen uptake (peakVO₂) and exercise duration in both studies, even after restriction to cardiorespiratory healthy participants. Statistically significant associations with oxygen uptake at anaerobic threshold (VO₂@AT), slope of the efficiency of ventilation in removing carbon dioxide, and peak oxygen pulse (VÉ/VCO₂ slope) occurred. Further, interactions with age were identified, such that mainly older individuals with higher levels of periodontal disease severity were associated with lower peakVO₂. Restricted to never smokers, associations with mean clinical attachment levels and the number of teeth mostly diminished, while associations of mean PPD with peakVO₂, VO₂@AT, VÉ/VCO₂ slope, and exercise duration in SHIP-1 and SHIP-Trend-0 were confirmed. In SHIP-1, mean peakVO₂ was 1,895 mL/min in participants with a mean PPD of 1.6 mm and 1,809 mL/min in participants with a mean PPD of 3.7 mm. To conclude, only mean PPD reflecting current disease severity was consistently linked to cardiorespiratory fitness in 2 cross-sectional samples of the general population. If confirmed in well-designed large-scale longitudinal studies, the association between periodontitis and cardiorespiratory fitness might provide a biologically plausible mechanism linking periodontitis with cardiometabolic diseases.

Impact of Powered Toothbrush Use and Interdental Cleaning on Oral Health

The long-term effectiveness of powered toothbrushes (PTBs) and interdental cleaning aids (IDAs) on a population level is unproven. We evaluated to what extent changes in PTB and IDA use may explain changes in periodontitis, caries, and tooth loss over the course of 17 y using data for adults (35 to 44 y) and seniors (65 to 74 y) from 3 independent cross-sectional surveys of the German Oral Health Studies (DMS). Oaxaca decomposition analyses assessed to what extent changes in mean probing depth (PD), number of caries-free surfaces, and number of teeth between 1) DMS III and DMS V and 2) DMS IV and DMS V could be explained by changes in PTB and IDA use. Between DMS III and V, PTB (adults: 33.5%; seniors: 28.5%) and IDA use (adults: 32.5%; seniors: 41.4%) increased along with an increase in mean PD, number of caries-free surfaces, and number of teeth. Among adults, IDA use contributed toward increased number of teeth between DMS III and V as well as DMS IV and V. In general, the estimates for adults were of lower magnitude. Among seniors between DMS III and V, PTB and IDA use explained a significant amount of explained change in the number of caries-free surfaces (1.72 and 5.80 out of 8.44, respectively) and the number of teeth (0.49 and 1.25 out of 2.19, respectively). Between DMS IV and V, PTB and IDA use contributed most of the explained change in caries-free surfaces (0.85 and 1.61 out of 2.72, respectively) and the number of teeth (0.25 and 0.46 out of 0.94, respectively) among seniors. In contrast to reported results from short-term clinical studies, in the long run, both PTB and IDA use contributed to increased number of caries-free healthy surfaces and teeth in both adults and seniors.

Evaluating Modeling and Validation Strategies for Tooth Loss

Prediction models learn patterns from available data (training) and are then validated on new data (testing). Prediction modeling is increasingly common in dental research. We aimed to evaluate how different model development and validation steps affect the predictive performance of tooth loss prediction models of patients with periodontitis. Two independent cohorts (627 patients, 11,651 teeth) were followed over a mean ± SD 18.2 ± 5.6 y (Kiel cohort) and 6.6 ± 2.9 y (Greifswald cohort). Tooth loss and 10 patient- and tooth-level predictors were recorded. The impact of different model development and validation steps was evaluated: 1) model complexity (logistic regression, recursive partitioning, random forest, extreme gradient boosting), 2) sample size (full data set or 10%, 25%, or 75% of cases dropped at random), 3) prediction periods (maximum 10, 15, or 20 y or uncensored), and 4) validation schemes (internal or external by centers/time). Tooth loss was generally a rare event (880 teeth were lost). All models showed limited sensitivity but high specificity. Patients' age and tooth loss at baseline as well as probing pocket depths showed high variable importance. More complex models (random forest, extreme gradient boosting) had no consistent advantages over simpler ones (logistic regression, recursive partitioning). Internal validation (in sample) overestimated the predictive power (area under the curve up to 0.90), while external validation (out of sample) found lower areas under the curve (range 0.62 to 0.82). Reducing the sample size decreased the predictive power, particularly for more complex models. Censoring the prediction period had only limited impact. When the model was trained in one period and tested in another, model outcomes were similar to the base case, indicating temporal validation as a valid option. No model showed higher accuracy than the no-information rate. In conclusion, none of the developed models would be useful in a clinical setting, despite high accuracy. During modeling, rigorous development and external validation should be applied and reported accordingly.

Construction of a Biological Age Score to Predict Tooth Loss over 10 Years

The aim of the present study was to construct a biological age score reflecting one’s physiologic capability and aging condition with respect to tooth loss over 10 y. From the follow-up to the population-based Study of Health in Pomerania (i.e., SHIP-2), 2,049 participants were studied for their baseline biomarker measures 10 y before (i.e., in SHIP-0). Metabolic and periodontal data were regressed onto chronological age to construct a score designated as “biological age.” For either sex separately, the impact of this individualized score was used to predict tooth loss in the follow-up cohort in comparison with each participant’s chronological age. Outcome data after 10 y with respect to tooth loss, periodontitis, obesity, and inflammation were shown to be better for biologically younger subjects than as expected by their chronological age, whereas for the older subjects, data were worse. Especially for tooth loss, a striking increase was observed in subjects whose biological age at baseline appeared to be higher than their chronological age. Biological age produced significantly better tooth loss predictions than chronological age ( P < 0.001). Areas under receiver operating characteristic curves for tooth loss of ≥3 teeth in men during follow-up were 0.811 and 0.745 for biological and chronological age, respectively. For women, these figures were 0.788 and 0.724. For total tooth loss, areas under the curve were 0.890 and 0.749 in men and 0.872 and 0.752 in women. Biological age combines various measures into a single score and allows identifying individuals at increased risk of tooth loss.

The Saliva Metabolome in Association to Oral Health Status

Periodontitis is one of the most prevalent oral diseases worldwide and is caused by multifactorial interactions between host and oral bacteria. Altered cellular metabolism of host and microbes releases a number of intermediary end products known as metabolites. There is an increasing interest in identifying metabolites from oral fluids such as saliva to widen the understanding of the complex pathogenesis of periodontitis. It is believed that some metabolites might serve as indicators toward early detection and screening of periodontitis and perhaps even for monitoring its prognosis in the future. Because contemporary periodontal screening methods are deficient, there is an urgent need for novel approaches in periodontal screening procedures. To this end, we associated oral parameters (clinical attachment level, periodontal probing depth, supragingival plaque, supragingival calculus, number of missing teeth, and removable denture) with a large set of salivary metabolites ( n = 284) obtained by mass spectrometry among a subsample ( n = 909) of nondiabetic participants from the Study of Health in Pomerania (SHIP-Trend-0). Linear regression analyses were performed in age-stratified groups and adjusted for potential confounders. A multifaceted image of associated metabolites ( n = 107) was revealed with considerable differences according to age groups. In the young (20 to 39 y) and middle-aged (40 to 59 y) groups, metabolites were predominantly associated with periodontal variables, whereas among the older subjects (≥60 y), tooth loss was strongly associated with metabolite levels. Metabolites associated with periodontal variables were clearly linked to tissue destruction, host defense mechanisms, and bacterial metabolism. Across all age groups, the bacterial metabolite phenylacetate was significantly associated with periodontal variables. Our results revealed alterations of the salivary metabolome in association with age and oral health status. Among our comprehensive panel of metabolites, periodontitis was significantly associated with the bacterial metabolite phenylacetate, a promising substance for further biomarker research.

Effect of Periodontal Treatment on HbA1c among Patients with Prediabetes

Evidence is limited regarding whether periodontal treatment improves hemoglobin A1c (HbA1c) among people with prediabetes and periodontal disease, and it is unknown whether improvement of metabolic status persists >3 mo. In an exploratory post hoc analysis of the multicenter randomized controlled trial “Antibiotika und Parodontitis” (Antibiotics and Periodontitis)—a prospective, stratified, double-blind study—we assessed whether nonsurgical periodontal treatment with or without an adjunctive systemic antibiotic treatment affects HbA1c and high-sensitivity C-reactive protein (hsCRP) levels among periodontitis patients with normal HbA1c (≤5.7%, n = 218), prediabetes (5.7% < HbA1c < 6.5%, n = 101), or unknown diabetes (HbA1c ≥ 6.5%, n = 8) over a period of 27.5 mo. Nonsurgical periodontal treatment reduced mean pocket probing depth by >1 mm in both groups. In the normal HbA1c group, HbA1c values remained unchanged at 5.0% (95% CI, 4.9% to 6.1%) during the observation period. Among periodontitis patients with prediabetes, HbA1c decreased from 5.9% (95% CI, 5.9% to 6.0%) to 5.4% (95% CI, 5.3% to 5.5%) at 15.5 mo and increased to 5.6% (95% CI, 5.4% to 5.7%) after 27.5 mo. At 27.5 mo, 46% of periodontitis patients with prediabetes had normal HbA1c levels, whereas 47.9% remained unchanged and 6.3% progressed to diabetes. Median hsCRP values were reduced in the normal HbA1c and prediabetes groups from 1.2 and 1.4 mg/L to 0.7 and 0.7 mg/L, respectively. Nonsurgical periodontal treatment may improve blood glucose values among periodontitis patients with prediabetes (ClinicalTrials.gov NCT00707369).

An ex vivo RNA trans-splicing strategy to correct human generalized severe epidermolysis bullosa simplex

Background

Generalized severe epidermolysis bullosa simplex (EBS‐gen sev) is a genetic blistering skin disease in which autosomal dominant mutations in either the keratin KRT5 or KRT14 genes lead to impaired function of the intermediate filament cytoskeleton in the basal epidermis. Here we present an ex vivo RNA trans‐splicing‐based therapeutic approach to correct the phenotype.

Objectives

To correct a mutation within exon 1 of the KRT14 gene, using a 5′‐trans‐splicing approach, where any mutation within the first seven exons could be replaced by a single therapeutic molecule.

Methods

A therapeutic RNA trans‐splicing molecule containing wild‐type exons 1–7 was stably transduced into an EBS patient‐derived keratinocyte line. Trans‐splicing was confirmed via reverse‐transcriptase polymerase chain reaction, Western blotting and immunofluorescence microscopy. Skin equivalents generated from corrected keratinocytes were grafted onto nude mice and analysed about 8 weeks post‐transplantation for regular epidermal stratification, trans‐splicing‐induced green fluorescent protein expression and blistering.

Results

Transplanted skin equivalents generated from trans‐splicing‐corrected patient keratinocytes showed a stable and blister‐free epidermis. KRT14 correction disrupted EBS‐gen sev‐associated proinflammatory signalling, as shown at the mRNA and protein levels. Disruption of the pathogenic feedback loop in addition to overall downregulation of KRT14 expression highlighted the effect of KRT14 correction on the EBS pathomechanism.

Conclusions

Our data demonstrate that trans‐splicing‐mediated mRNA therapy is an effective method for the correction of dominantly inherited KRT14 mutations at the transcriptional level. This results in the rescue of the EBS‐gen sev phenotype and stabilization of the epidermis in a xenograft mouse model.

What's already known about this topic?

RTM163, described in this study, was previously used in a transient in vitro transfection system, where the ability to correct KRT14 at the mRNA level was demonstrated.

What does this study add?

In this study, we stably transduced RTM163 in a second patient‐derived keratinocyte line.

Successful trans‐splicing was confirmed in this cell line.

The expression of disease‐related marker genes, which are characteristically deregulated in epidermolysis bullosa simplex, were analysed.

For the first time this study showed that RNA trans‐splicing molecule‐transduced patient keratinocytes can differentiate into a phenotypically normal and blister‐free epidermis in a xenograft mouse model.

What is the translational message?

This study shows the feasibility of using spliceosome‐mediated RNA trans‐splicing to generate a stable and blister‐free epidermis in vivo.

Combined with pre‐existing ex vivo gene therapeutic methods, this might be a valid option for future treatments of dominantly inherited genodermatoses.

Linked Comment: Bremer and van den Akker. Br J Dermatol 2019; 180:17–19.

Integration of Murine and Human Studies for Mapping Periodontitis Susceptibility

Periodontitis is one of the most common inflammatory human diseases with a strong genetic component. Due to the limited sample size of available periodontitis cohorts and the underlying trait heterogeneity, genome-wide association studies (GWASs) of chronic periodontitis (CP) have largely been unsuccessful in identifying common susceptibility factors. A combination of quantitative trait loci (QTL) mapping in mice with association studies in humans has the potential to discover novel risk loci. To this end, we assessed alveolar bone loss in response to experimental periodontal infection in 25 lines (286 mice) from the Collaborative Cross (CC) mouse population using micro-computed tomography (µCT) analysis. The orthologous human chromosomal regions of the significant QTL were analyzed for association using imputed genotype data (OmniExpress BeadChip arrays) derived from case-control samples of aggressive periodontitis (AgP; 896 cases, 7,104 controls) and chronic periodontitis (CP; 2,746 cases, 1,864 controls) of northwest European and European American descent, respectively. In the mouse genome, QTL mapping revealed 2 significant loci (-log P = 5.3; false discovery rate = 0.06) on chromosomes 1 ( Perio3) and 14 ( Perio4). The mapping resolution ranged from ~1.5 to 3 Mb. Perio3 overlaps with a previously reported QTL associated with residual bone volume in F2 cross and includes the murine gene Ccdc121. Its human orthologue showed previously a nominal significant association with CP in humans. Use of variation data from the genomes of the CC founder strains further refined the QTL and suggested 7 candidate genes ( CAPN8, DUSP23, PCDH17, SNORA17, PCDH9, LECT1, and LECT2). We found no evidence of association of these candidates with the human orthologues. In conclusion, the CC populations enabled mapping of confined QTL that confer susceptibility to alveolar bone loss in mice and larger human phenotype-genotype samples and additional expression data from gingival tissues are likely required to identify true positive signals.

Influence of Age and Tooth Loss on Masticatory Muscles Characteristics: A Population Based MR Imaging Study

BACKGROUND

Aging is associated with a decline in masticatory muscles mass and performance. The present study aims to examine the differences in the cross-sectional areas of the masseter, medial and lateral pterygoid muscles in relation to age and the present dental status in a population-based magnetic resonance imaging study.

METHODS

This cross sectional study involved 747 subjects aged between 30-89 years (344 male, 403 female) who underwent both a whole body MRI and a full oral examination. The cross-sectional areas of the masseter, medial and lateral pterygoid muscles were measured from MRI images using the software Osirix. Dental and prosthetic status data from the oral examination were classified according to Eichner index. The method of generalized least squares, also called growth curve model, was used to examine the associations between the cross-sectional areas, age and tooth status.

RESULTS

The cross-sectional area of the lateral pterygoid muscle decreased substantially with age in women but did not depend on age in men. The medial pterygoid muscle depended on age but an effect modification by gender was uncertain. Masseter muscle was weakly associated with age but strongly associated with the number of teeth in both genders.

CONCLUSIONS

Our findings suggest that age has a heterogeneous effect on masticatory muscles. This indicates that age related changes to the masticatory muscles are muscle specific and are not consistent between the different muscles.

Do Genetic Markers of Inflammation Modify the Relationship between Periodontitis and Nonalcoholic Fatty Liver Disease? Findings from the SHIP Study

An association between periodontitis and nonalcoholic fatty liver disease (NAFLD) has been reported by experimental animal and epidemiologic studies. This study investigated whether circulating levels of serum C-reactive protein (CRP) and a weighted genetic CRP score representing markers of inflammatory burden modify the association between periodontitis and NAFLD. Data came from 2,481 participants of the Study of Health in Pomerania who attended baseline examination that occurred between 1997 and 2001. Periodontitis was defined as the percentage of sites (0%, <30%, ≥30%) with probing pocket depth (PD) ≥4 mm, and NAFLD status was determined using liver ultrasound assessment. Serum CRP levels were assayed at a central laboratory, and single-nucleotide polymorphisms previously identified through genome-wide association studies as robustly associated with serum CRP were combined into a weighted genetic CRP score (wGS_CRP). Logistic regression models estimated the association between periodontitis and NAFLD within strata of serum CRP and separately within strata of the wGS_CRP. The prevalence of NAFLD was 26.4% (95% confidence interval [CI], 24.6, 28.1) while 17.8% (95% CI, 16.0-19.6) had ≥30% of sites with PD ≥4 mm. Whereas the wGS_CRP was not a modifier ( P_interaction = 0.8) on the multiplicative scale, serum CRP modified the relationship between periodontitis and NAFLD ( P_interaction = 0.01). The covariate-adjusted prevalence odds ratio of NAFLD comparing participants with ≥30% of sites with PD ≥4 mm to those with no site affected was 2.39 (95% CI, 1.32-4.31) among participants with serum CRP <1 mg/L. The corresponding estimate was 0.97 (95% CI, 0.57-1.66) for participants with serum CRP levels of 1 to 3 mg/L and 1.12 (95% CI, 0.65-1.93) for participants with serum CRP >3 mg/L. Periodontitis was positively associated with higher prevalence odds of NAFLD, and this relationship was modified by serum CRP levels.

The PF4/PPBP/CXCL5 Gene Cluster Is Associated with Periodontitis

Periodontitis is a common dysbiotic inflammatory disease with an estimated heritability of 50%. Due to the limited sample size of available periodontitis cohorts and the underlying trait heterogeneity, genome-wide association studies (GWAS) of chronic periodontitis (CP) have been unsuccessful in discovering susceptibility factors. A strategy that combines agnostic GWAS with a well-powered candidate-gene approach has the potential to discover novel loci. We combined RNA-seq data from gingival tissues with quantitative trait loci (QTLs) that were identified in a F₂-cross of mice resistant and susceptible to infection with oral bacterial pathogens. Four genes, which were located within the mapped QTLs, showed differential expression. The chromosomal regions across the human orthologous were interrogated for putative periodontitis-associated variants using existing GWAS data from a German case-control sample of aggressive periodontitis (AgP; 651 cases, 4,001 controls), the most severe and early onset form of periodontitis. Two haplotype blocks, one upstream to the coding region of UGT2A1 (rs146712414, P = 9.1 × 10^-5; odds ratio [OR], 1.34; 95% confidence interval [CI], 1.16-1.56) and one downstream of the genes PF4/PPBP/CXCL5 (rs1595009, P = 1.3 × 10^-4; OR, 1.32; 95% CI, 1.15-1.52), were associated with AgP. The association of rs1595009 was validated in an independent cohort of CP of European Americans (1,961 cases and 1,864 controls; P = 0.03; OR, 1.45; 95% CI, 1.01-1.29). This association was further replicated in another sample of 399 German CP cases (disease onset <60 y of age) and 1,633 controls ( P = 0.03; OR, 1.75; 95% CI, 1.06-2.90). The combined estimates of association from all samples were P = 2.9 × 10^-5 (OR, 1.2; 95% CI, 1.1-1.3). This study shows the strength of combining QTL mapping and RNA-Seq data from a mouse model with association studies in human case-control samples to identify genetic risk variants of periodontitis.

GWAS Identifies New Loci for Painful Temporomandibular Disorder: Hispanic Community Health Study/Study of Latinos

Temporomandibular disorder (TMD) is a musculoskeletal condition characterized by pain and reduced function in the temporomandibular joint and/or associated masticatory musculature. Prevalence in the United States is 5% and twice as high among women as men. We conducted a discovery genome-wide association study (GWAS) of TMD in 10,153 participants (769 cases, 9,384 controls) of the US Hispanic Community Health Study/Study of Latinos (HCHS/SOL). The most promising single-nucleotide polymorphisms (SNPs) were tested in meta-analysis of 4 independent cohorts. One replication cohort was from the United States, and the others were from Germany, Finland, and Brazil, totaling 1,911 TMD cases and 6,903 controls. A locus near the sarcoglycan alpha ( SGCA), rs4794106, was suggestive in the discovery analysis ( P = 2.6 × 10⁶) and replicated (i.e., 1-tailed P = 0.016) in the Brazilian cohort. In the discovery cohort, sex-stratified analysis identified 2 additional genome-wide significant loci in females. One lying upstream of the relaxin/insulin-like family peptide receptor 2 ( RXP2) (chromosome 13, rs60249166, odds ratio [OR] = 0.65, P = 3.6 × 10^-8) was replicated among females in the meta-analysis (1-tailed P = 0.052). The other (chromosome 17, rs1531554, OR = 0.68, P = 2.9 × 10^-8) was replicated among females (1-tailed P = 0.002), as well as replicated in meta-analysis of both sexes (1-tailed P = 0.021). A novel locus at genome-wide level of significance (rs73460075, OR = 0.56, P = 3.8 × 10^-8) in the intron of the dystrophin gene DMD (X chromosome), and a suggestive locus on chromosome 7 (rs73271865, P = 2.9 × 10^-7) upstream of the Sp4 Transcription Factor ( SP4) gene were identified in the discovery cohort, but neither of these was replicated. The SGCA gene encodes SGCA, which is involved in the cellular structure of muscle fibers and, along with DMD, forms part of the dystrophin-glycoprotein complex. Functional annotation suggested that several of these variants reside in loci that regulate processes relevant to TMD pathobiologic processes.

Magnesium Deficiency is Associated with Periodontal Disease

In the multifactorial pathogenesis of periodontitis, there are still unknown factors influencing the outcome of the disease. An association between magnesium and periodontitis has been suggested by preliminary studies. However, relevant clinical data are lacking. We investigated the association between magnesium status and periodontal health in a population-based analysis. We conducted a cross-sectional epidemiological investigation involving 4290 subjects aged 20–80 yrs. We recorded periodontal risk factors and determined concentrations of serum magnesium and calcium, relating them to periodontal parameters. In a matched-pair study, 60 subjects using oral magnesium-containing drugs and 120 without were compared. In subjects aged 40 yrs and older, increased serum Mg/Ca was significantly associated with reduced probing depth (p < 0.001), less attachment loss (p = 0.006), and a higher number of remaining teeth (p = 0.005). Subjects taking Mg drugs showed less attachment loss (p < 0.01) and more remaining teeth than did their matched counterparts. These results suggest that nutritional magnesium supplementation may improve periodontal health.

Reduced Bone Stiffness in Women Is Associated with Clinical Attachment and Tooth Loss

The authors evaluated the association of reduced bone stiffness of the calcaneus with clinical attachment loss (CAL) and tooth loss. The authors analyzed data from 4,678 subjects (2,384 women), aged 20 to 88 y, from the second follow-up of the population-based Study of Health in Pomerania (SHIP-2) and the baseline examination of the SHIP-Trend cohort. Bone stiffness, characterized by the stiffness index (SI) and the osteoporotic fracture risk (OFR), was assessed by quantitative ultrasound of the heel. SI and OFR were significantly associated with the mean CAL in women. While 1) the SI showed a significant association with the mean CAL and 2) the OFR with the median number of teeth in just the postmenopausal women, the OFR showed a significant association with mean CAL for both pre- and postmenopausal women. In postmenopausal women, a 10-unit increase in the SI was associated with a decrease in the mean CAL of 0.05 mm (95% confidence interval [CI]: –0.10 to 0.00; P = 0.046). Moreover, the adjusted median number of teeth was 21.4 (95% CI: 20.9 to 21.9) among the postmenopausal women with a low OFR, while it was 19.1 (95% CI: 17.8 to 20.3; P = 0.001) among the postmenopausal women with a high OFR. For the premenopausal women with a low OFR, the mean CAL was 1.60 mm (95% CI: 1.53 to 1.66), while for the premenopausal women with a high OFR, it was 2.24 mm (95% CI: 1.78 to 2.69; P = 0.006). Reduced bone stiffness was associated with clinical attachment and tooth loss in women but not in men.

Exome Variant Analysis of Chronic Periodontitis in 2 Large Cohort Studies

Periodontitis is characterized by inflammation of the gingival tissue. The main risk factors are socioeconomic factors, sex, age, smoking, and diabetes, but periodontal disease has also a genetic background. Previous genome-wide association studies failed to reveal genome-wide significant associations of single common single-nucleotide polymorphisms with chronic periodontitis. Using the Illumina ExomeChip data of 6,576 participants of the German population-based cohort studies Study of Health in Pomerania (SHIP) and SHIP-Trend, the authors performed single variant and also gene-based association studies of rare and common exonic variations on different periodontal case definitions. Although our study comprised the largest sample size to date to assess genetic predisposition for chronic periodontitis, the authors found no significant association. This study emphasizes that for chronic periodontitis, large sample sizes will be necessary to find genetic associations, even when examining rare genetic variants.

Magnesium/Calcium Ratio in Serum Predicts Periodontitis and Tooth Loss in a 5-Year Follow-up

In the cross-sectional Study of Health in Pomerania (SHIP-0), subjects with an adequate magnesium supply had a lower risk of periodontal disease and more teeth than those with low magnesium levels. The authors analyzed 5-y follow-up data (SHIP-1) to determine whether the baseline magnesium levels had a long-term effect on attachment level and number of teeth lost. Of the participants examined dentally in the baseline study, 3,300 (75%) were examined for progression or recession of periodontal attachment level after 5 y. For 2,432 subjects, the authors related the outcome variables of periodontal attachment level and tooth loss to baseline characteristics, especially serum magnesium and calcium concentrations, as well as systemic markers of inflammation. The progression of periodontitis was associated with the magnesium/calcium (Mg/Ca) ratio at baseline in a dose-dependent manner. Progression of mean attachment loss was prevented in the upper quartile of the Mg/Ca ratio ( P < 0.001) with antagonistic effects of magnesium and calcium irrespective of inflammatory state. With respect to tooth loss, Mg/Ca exerted dimorphic effects. In inflammatory states as indicated by high C-reactive protein (>3 mg/L), tooth loss was prevented in subjects with high Mg/Ca ratio (incidence rate ratio = 0.60, 95% confidence interval: 0.45 to 0.80, P = 0.001), but the contrary was observed in subjects with low C-reactive protein levels (incidence rate ratio = 1.14, 95% confidence interval: 0.97 to 1.34, NS). Similar results were observed with stratifying the regression on tooth loss by interleukin 6 or fibrinogen threshold. An adequate magnesium serum level and Mg/Ca balance may prevent progression of attachment level and tooth loss, especially in inflammatory states. Knowledge Transfer Statement: The results of this study present evidence that an adequate magnesium supply may be important in the prevention of periodontal diseases and future tooth loss. A diet high in magnesium could improve periodontal health, notwithstanding its beneficial effects on systemic disease. In populations with a high prevalence of hypomagnesemia, additional intake of supplements is advisable.

Gene transcripts associated with muscle strength: a CHARGE meta-analysis of 7,781 persons

Lower muscle strength in midlife predicts disability and mortality in later life. Blood-borne factors, including growth differentiation factor 11 (GDF11), have been linked to muscle regeneration in animal models. We aimed to identify gene transcripts associated with muscle strength in adults. Meta-analysis of whole blood gene expression (overall 17,534 unique genes measured by microarray) and hand-grip strength in four independent cohorts (n = 7,781, ages: 20-104 yr, weighted mean = 56), adjusted for age, sex, height, weight, and leukocyte subtypes. Separate analyses were performed in subsets (older/younger than 60, men/women). Expression levels of 221 genes were associated with strength after adjustment for cofactors and for multiple statistical testing, including ALAS2 (rate-limiting enzyme in heme synthesis), PRF1 (perforin, a cytotoxic protein associated with inflammation), IGF1R, and IGF2BP2 (both insulin like growth factor related). We identified statistical enrichment for hemoglobin biosynthesis, innate immune activation, and the stress response. Ten genes were associated only in younger individuals, four in men only and one in women only. For example, PIK3R2 (a negative regulator of PI3K/AKT growth pathway) was negatively associated with muscle strength in younger (<60 yr) individuals but not older (≥ 60 yr). We also show that 115 genes (52%) have not previously been linked to muscle in NCBI PubMed abstracts. This first large-scale transcriptome study of muscle strength in human adults confirmed associations with known pathways and provides new evidence for over half of the genes identified. There may be age- and sex-specific gene expression signatures in blood for muscle strength.

Sex Differences of Tooth Loss and Obesity on Systemic Markers of Inflammation

Sex-specific differences in the incidence of periodontitis and tooth loss may be related to different phenotypes of obesity and their associations with low-grade inflammation. The aim of this study was to evaluate associations of adiposity and low-grade inflammation with tooth loss in men and women. Follow-up data of 2,714 participants from the cohort of Study of Health in Pomerania were analyzed for anthropometric measures, periodontitis, tooth loss, C-reactive protein (CRP), and interleukin 6. Regression analyses were used to estimate the effect of obesity on tooth loss within sex strata. During the follow-up period, men lost more teeth in relation to their obesity status than did women. In contrast, there was a steeper increase in CRP levels across obesity levels in women as compared to men. Incidence rate ratio (IRR) of tooth loss associated with elevated CRP, however, was higher in men (IRR = 1.50; 95% confidence interval [CI]: 1.27, 1.77) than women (IRR = 1.18; 95% CI: 1.02, 1.37). Negative binomial regression with number of lost teeth as outcome revealed dose-response dependencies on body mass index and waist-to-hip ratio. Adjusted for covariates, the IRR of tooth loss associated with the third tertile of waist-to-hip ratio was 1.37 (95% CI: 1.04, 1.80) and 1.53 (95% CI: 1.14, 2.05) in men and women, respectively. Tooth loss related to CRP cutoff of 2 mg/L was significant in men (IRR = 1.33; 95% CI: 1.07, 1.66; p = .006) but not in women (IRR = 0.92; 95% CI: 0.73, 1.17; p = .689). This study suggests that both adiposity and subclinical inflammation affect tooth loss, with distinct differences between men and women. Obesity as a risk factor of tooth loss is particularly related to CRP in men but not in women.

Prospective Study of Serum 25-hydroxy Vitamin D and Tooth Loss

Vitamin D deficiency and oral diseases (periodontitis, caries, and tooth loss) are highly prevalent in Germany. Previous studies suggested that vitamin D might be a modifiable and protective factor for periodontitis, caries, and tooth loss. However, prospective studies investigating such associations are limited. We explored the association between the concentration of serum 25-hydroxy vitamin D (25OHD) and incidence of tooth loss, progression of clinical attachment loss (CAL) ≥ 3 mm, and progression of restorative and caries status in a population-based longitudinal study. We analyzed data from 1,904 participants from the Study of Health in Pomerania with a five-year follow-up. Generalized estimating equation models were applied to evaluate tooth-specific associations between serum 25OHD and incidence of tooth loss, progression of CAL ≥ 3 mm, and progression of restorative and caries status. Age, sex, education, smoking status, alcohol drinking, waist circumference, dental visit frequency, reasons of dental visit, vitamin D or calcium supplements, and season of blood draw were considered as confounders. Serum 25OHD was inversely associated with incidence of tooth loss. A significant dose-response relationship (p = .0022) was observed across the quintiles of serum 25OHD. After adjusting for multiple confounders, each 10-µg/L increase of serum 25OHD was associated with a 13% decreased risk of tooth loss (risk ratio: 0.87; 95% confidence interval: 0.79, 0.96). The association was attenuated for changes of CAL ≥ 3 mm when adjusting for multiple confounders. No significant association was found between serum 25OHD and caries progression. Vitamin D might be a protective factor for tooth loss. The effect might partially be mediated by its effect on periodontitis.

Perforated sigmoid diverticulitis in the presence of toxic epidermal necrolysis

Even though the incidence of toxic epidermal necrolysis (TEN) is low, it is also associated with a high mortality rate. The condition predominantly affects the skin, but may also affect the gastrointestinal tract, dramatically increasing mortality. We present a case of perforated sigmoid diverticulitis in the presence of TEN. The patient was taking medication, known to be a risk factor, and presented an affected total body surface area and temporal development similar to previously reported cases of TEN. Characteristic abdominal symptoms, however, were missing. Gastrointestinal involvement in TEN appears to be a poor prognostic factor; medical staff must therefore be alert to patients with TEN who complain of abdominal discomfort. The exact pathogenesis, however, remains unclear.

Efficacy of different carrier gases for barrier discharge plasma generation compared to chlorhexidine on the survival of Pseudomonas aeruginosa embedded in biofilm in vitro

Because of its antimicrobial properties, nonthermal plasma could serve as an alternative to chemical antisepsis in wound treatment. Therefore, this study investigated the inactivation of biofilm-embedded Pseudomonas aeruginosa SG81 by a surface barrier-discharged (SBD) plasma for 30, 60, 150 and 300 s. In order to optimize the efficacy of the plasma, different carrier gases (argon, argon admixed with 1% oxygen, and argon with increased humidity up to approx. 80%) were tested and compared against 0.1% chlorhexidine digluconate (CHG) exposure for 600 s. The antimicrobial efficacy was determined by calculating the difference between the numbers of colony-forming units (CFU) of treated and untreated biofilms. Living bacteria were distinguished from dead by fluorescent staining and confocal laser scanning microscopy. Both SBD plasmas and CHG showed significant antimicrobial effects compared to the untreated control. However, plasma treatment led to a higher antimicrobial reduction (argon plasma 4.9 log10 CFU/cm(2), argon with admixed oxygen 3 log10 CFU/cm(2), and with increased gas humidity 2.7 log10 CFU/cm(2) after 300 s) compared to CHG. In conclusion, SBD plasma is suitable as an alternative to CHG for inactivation of Pseudomonas aeruginosa embedded in biofilm. Further development of SBD plasma sources and research on the role of carrier gases and humidity may allow their clinical application for wound management in the future.

Association of heat shock proteins with all-cause mortality

Experimental mild heat shock is widely known as an intervention that results in extended longevity in various models along the evolutionary lineage. Heat shock proteins (HSPs) are highly upregulated immediately after a heat shock. The elevation in HSP levels was shown to inhibit stress-mediated cell death, and recent experiments indicate a highly versatile role for these proteins as inhibitors of programmed cell death. In this study, we examined common genetic variations in 31 genes encoding all members of the HSP70, small HSP, and heat shock factor (HSF) families for their association with all-cause mortality. Our discovery cohort was the Rotterdam study (RS1) containing 5,974 participants aged 55 years and older (3,174 deaths). We assessed 4,430 single nucleotide polymorphisms (SNPs) using the HumanHap550K Genotyping BeadChip from Illumina. After adjusting for multiple testing by permutation analysis, three SNPs showed evidence for association with all-cause mortality in RS1. These findings were followed in eight independent population-based cohorts, leading to a total of 25,007 participants (8,444 deaths). In the replication phase, only HSF2 (rs1416733) remained significantly associated with all-cause mortality. Rs1416733 is a known cis-eQTL for HSF2. Our findings suggest a role of HSF2 in all-cause mortality.

Quantitative analysis of the intra- and inter-subject variability of the whole salivary proteome

BACKGROUND AND OBJECTIVE

Interest in human saliva is increasing for disease-specific biomarker discovery studies. However, protein composition of whole saliva can grossly vary with physiological and environmental factors over time and it comprises human as well as bacterial proteins.

MATERIAL AND METHODS

We compared intra- and inter-subject variabilities using complementary gel-based (two-dimensional difference gel electrophoresis, 2-D DIGE) and gel-free (liquid chromatography tandem mass spectrometry, LC-MS/MS) proteomics profiling of saliva. Unstimulated whole saliva of four subjects was examined at three different time-points (08.00 h, 12.00 h and 17.00 h) and variability of the saliva proteome was analyzed on two successive days by LC-MS/MS.

RESULTS

In the 2-D DIGE experiment, the median coefficient of variation (CV) for intra-subject variability was significantly lower (CV of 0.39) than that for inter-subject variability (CV of 0.57; CV of technical replicates 0.17). LC-MS/MS data confirmed the significantly lower variation within subjects over time (CV of 0.37) than the inter-subject variability (CV of 0.53; CV of technical replicates 0.11), and that the inter-subject variability was not time-dependent.

CONCLUSION

Both techniques revealed similar trends of variations on technical, intra- and inter-subject level but provided peptide and protein focused information and should thus be used as complementary approaches. The data presented indicate that 2-D DIGE as well as LC-MS/MS approaches are suitable for biomarker screening in saliva.

The effect of catechol-O-methyltransferase polymorphisms on pain is modified by depressive symptoms

BACKGROUND

Variations within the catechol-O-methyltransferase (COMT) gene have been associated with pain severity in temporomandibular disorders (TMDs). Psychological factors such as personal conflicts, life stress and depression, are well known to be associated with onset, severity and chronicity of pain disorders.

AIM

We hypothesized that the relationship between the COMT gene and TMD pain is modified by depressive symptoms.

METHODS

Cross-sectional data from the population-based Study of Health in Pomerania (SHIP) in Germany were used to estimate additive interactions between depressive symptoms and 22 single-nucleotide polymorphisms (SNPs) of the COMT gene and the neighbouring thioredoxin reductase 2 (TXNRD2) gene on TMD pain. All participants were Caucasian subjects from a rural area in Northeast Germany. After exclusion of 79 subjects with antidepressant medication, 29.9% of the remaining 3904 subjects reported lifetime depressive symptoms. TMD pain was assessed by a standardized clinical examination. Among various TMD signs, only those that assessed muscle or joint pain on palpation were used as recommended.

RESULTS

Six SNPs from the first of three COMT/TXNRD2 haploblocks interacted with depressive symptoms on TMD pain (smallest p-value: 2.7 × 10(-10) ). In subjects without depressive symptoms, rs5993882 was identified as the SNP most likely to be related to TMD pain. In subjects with symptoms of depression, rs1544325 was the corresponding top COMT SNP.

CONCLUSIONS

Our results indicate that variants within the COMT gene are associated with pain perception. However, this association is highly moderated by the absence or presence of lifetime depressive symptoms.

[Diabetes mellitus and periodontitis. Bidirectional relationship and clinical implications. A consensus document]

Diabetes and periodontitis are chronic diseases with an increasing prevalence in the German population. There is a bi-directional relationship between both diseases. Diabetes promotes the occurrence, the progression and the severity of periodontitis. Periodontitis complicates the glycemic control of diabetes, increases the risk of diabetes-associated complications and possibly even of its onset. In view of the existing evidence, that is still not sufficiently communicated within the medical community, an expert panel consisting of four diabetologists and four periodontists has addressed the following questions: What is the effect of diabetes mellitus on periodontitis and on periodontal therapy? What is the effect of periodontitis on diabetes mellitus? What are the practical consequences, that result for interdisciplinary treatment strategies? The treatment of periodontal infections should become an integral part of the management of diabetes, whereas glycemic control is a prerequisite for successful periodontal therapy.

Development of CLL in the TCL1 transgenic mouse model is associated with severe skewing of the T-cell compartment homologous to human CLL

Chronic lymphocytic leukemia (CLL) cells require complex microenvironmental and immunologic interactions to survive and proliferate. Such interactions might be best recreated in animal models; however, this needs extensive verification. We therefore investigated the composition of the T-cell compartment in the Eμ-TCL1 transgenic mouse, currently the most widely used murine model for CLL. Immunophenotyping and transplant approaches were used to define T-cell subsets at various stages of CLL. Analogous to human CLL, we observed a skewing of T-cell subsets from naive to antigen-experienced memory T cells that was more pronounced in lymph nodes than in blood. Transplantation of CLL into non-transgenic recipients was feasible without immunosuppression in a pure C57BL/6 background and resulted in the prominent skewing of the T cells of the recipient mice. Both in spontaneously developed CLL and in the transplantation setting, a loss in T-cell receptor diversity was observed, with a relevant number of clonal T-cell populations arising. This suggests that antigen-dependent differentiation toward the T memory pool is initiated by murine CLL cells. In summary, we validate the TCL1 transgenic mouse model for analysis of T-cell phenotypes and suggest a CLL-dependent antigen-driven skewing of T cells in these mice.

Signs and symptoms of temporomandibular disorders and the incidence of tinnitus

In a cross-sectional analysis of data from the Study of Health in Pomerania (SHIP 0), temporomandibular disorders (TMD) were the strongest predictors for tinnitus beside headache. The aim of this study was to investigate whether signs and symptoms of TMD can be identified as risk factors for developing tinnitus. The SHIP 1 is a population-based 5-year longitudinal study intended to systematically describe the prevalence of and risk factors for diseases common in the population of Pomerania in northern Germany. A total of 3300 subjects (76% response) were reevaluated after 5 years for tinnitus and signs and symptoms of TMD using the same questionnaires and examination tools as baseline. To estimate the relative risk (RR) appropriately, a modified Poisson regression was used. After exclusion of prevalent cases with diagnosed tinnitus, 3134 subjects were analysed. Among the 191 exposed subjects with palpation pain in the temporomandibular joint (TMJ), 24 subjects (12·6%) received diagnosed tinnitus after 5 years, whereas among the 2643 unexposed subjects 142 subjects (5·8%) received tinnitus yielding a risk difference of 7·7% (95% confidence interval [CI]: 3·0%-12·5%) and a risk ratio of 2·60 (95% CI: 1·7-3·9). The risk ratio was 2·4 (95% CI: 1·6-3·7) after adjustment for gender, age, school education and frequent headache. Pain on palpation of the TMJ, however, did not worsen the prognosis for tinnitus in prevalent tinnitus cases (RR = 0·8, P = 0·288). Signs of TMD are a risk factor for the development of tinnitus.

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.

The factors associated with body mass index in adults from the study of health in Pomerania (SHIP-0), Germany

OBJECTIVE

To investigate the relation between dental status, BMI and systemic diseases and to evaluate the risk factors for having a higher BMI.

MATERIALS AND METHODS

Apopulation based cross sectional study of 6248 subjects aged 18-80 years (response of 68.8%, n=4310) was conducted in the Study of Health in Pomerania (SHIP-0). Socio-demographic, medical and oral health information was recorded by 5 dentists at two similarly equipped medical/dental services in the cities of Greifswald and Stralsund. Bivariate statistics, multivariate statistics, linear and logistic regression models were performed to assess the relationship between following covariates: gender, educational level, family status, social activities, income, quality of life (SF-12), smoking, alcohol abuse, diabetes, renal disease, high blood pressure, dental status and high physical activity.

RESULTS

Significant risk factors for subjects having a higher BMI were: high blood pressure (OR=2.28), diabetes (OR=2.10), educational level (low: OR=1.49; medium OR=1.27), male (OR=1.32) and former smoker (OR=1.20). whereas young age, being single and being dentate (natural teeth, replaced teeth or fixed teeth) was shown to be protective for having a "high" BMI.

CONCLUSION

The most important predictors of BMI were shown to be social and medical factors. Dental factors are most significantly influenced by social factors and also exhibit an important impact on BMI.