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Objectives: The objectives were to: (i) assess the accuracy of dental data for adults obtained from the Swedish Quality Register on Caries and Periodontitis (SKaPa); (ii) explore whether Latent Class Analysis (LCA) can identify groups of people based on caries data; and (iii) characterise the dental, medical and behavioural characteristics of people in the LCA-derived classes.

Methods: Caries data from the SKaPa register were compared with clinical data collected by five experienced dentists in a nested subgroup of the Malmö Offspring Study (MOS), namely the Malmö Offspring Dental Study (MODS) (n = 724) for validation. Dental data from SKaPa were then used to classify 61 984 adult participants of the Västerbotten Intervention Programme (VIP) into five classes using LCA and DMFS-based quintile ranking, respectively. Dental status (including caries progression over 5 years), medical, anthropometric and behavioural characteristics were compared between the groups. Analyses were replicated in 2767 adults in the MOS.

Results: DMFS-scores and number of teeth recorded within −2 to +2 years showed excellent agreement between the SKaPa and reference data with intra-class correlations > 0.90. The five LCA classes differed in mean DMFS from 10.0 to 94.4. There were strong associations between LCA class and health, and health and behavioural measures respectively, including some associations that were not detected using DMFS-ranked quintile groups. LCA class was associated with incremental change in DMFS, DFS, and number of teeth. The results in the MOS cohort were consistent with the results in the VIP cohort.

Conclusions: Dental data for adults from the SKaPa registry were considered accurate within 2 years of recording. The LCA approach can classify participants into caries subtypes based on dental charting. These groups differ in health and behavioural characteristics and future caries increment. The LCA approach may capture some information that is missing from DMFS-ranked quintile groups, but is also heavily influenced by total DMFS, meaning that applying LCA in cumulative, highly age-determined diseases, such as caries, is a challenge.

Introduction: Periodontitis is associated with rheumatoid arthritis (RA). One hypothesis posits that this connection arises from the formation of autoantibodies against citrullinated proteins (ACPA) in inflamed gums, possibly triggered by Porphyromonas gingivalis. We previously demonstrated an increased antibody response to P. gingivalis arginine gingipains (anti-Rgp IgG), not only in individuals with severe periodontitis compared to controls, but in RA versus controls, with an association to ACPA. In the present study, we set out to further explore the relationship between anti-Rgp IgG, ACPA and periodontitis, including clinical periodontal parameters, in the large and well-characterized PerioGene North case-control study.

Methods: We measured serum levels of anti-Rgp and ACPA IgG by enzyme-linked immunosorbent assay (ELISA), in 478 patients with periodontitis and 509 periodontally healthy controls within PerioGene North. Subsequently, anti-Rgp IgG levels and ACPA status were analysed in relation to periodontitis and clinical periodontal parameters.

Results: Serum anti-Rgp IgG levels were elevated in cases versus controls (p< 0.001). However, receiver operating characteristic (ROC) curve analysis revealed that anti-Rgp IgG could not efficiently discriminate cases from controls (AUC= 0.63; 95% CI: 0.60 – 0.66). Among cases, increased anti-Rgp IgG levels associated with high periodontal inflammation and advanced alveolar bone loss (p<0.001 for both). An ACPA response was detected in 15 (3.1%) cases and 6 (1.2%) controls (p=0.033), but no association to periodontitis was evident after adjustment for age and smoking and anti-Rgp IgG levels did not differ between ACPA-positive and ACPA-negative individuals.

Conclusion: We show that anti-Rgp IgG identifies a subgroup of periodontitis patients with high degree of periodontal inflammation and advanced alveolar bone loss, but we do not find support for a link between periodontitis or anti-Rgp IgG and ACPA status in PerioGene North. Given the association between anti-Rgp and alveolar bone loss, the mechanistic role of gingipains in bone resorption should be experimentally explored.

Caries is a partially heritable disease, raising the possibility that a polygenic score (PS, a summary of an individual’s genetic propensity for disease) might be a useful tool for risk assessment. To date, PS for some diseases have shown clinical utility, although no PS for caries has been evaluated. The objective of the study was to test whether a PS for caries is associated with disease experience or increment in a cohort of Swedish adults. A genome-wide PS for caries was trained using the results of a published genome-wide association meta-analysis and constructed in an independent cohort of 15,460 Swedish adults. Electronic dental records from the Swedish Quality Registry for Caries and Periodontitis (SKaPa) were used to compute the decayed, missing, and filled tooth surfaces (DMFS) index and the number of remaining teeth. The performance of the PS was evaluated by testing the association between the PS and DMFS at a single dental examination, as well as between the PS and the rate of change in DMFS. Participants in the highest and lowest deciles of PS had a mean DMFS of 63.5 and 46.3, respectively. A regression analysis confirmed this association where a 1 standard deviation increase in PS was associated with approximately 4-unit higher DMFS (P < 2 × 10⁻¹⁶). Participants with the highest decile of PS also had greater change in DMFS during follow-up. Results were robust to sensitivity analysis, which adjusted for age, age squared, sex, and the first 20 genetic principal components. Mediation analysis suggested that tooth loss was a strong mediating factor in the association between PS and DMFS but also supported a direct genetic effect on caries. In this cohort, there are clinically meaningful differences in DMFS between participants with high and low PS for caries. The results highlight the potential role of genomic data in improving caries risk assessment.

Prolonged use of antibacterial mouthwash is linked to an increased risk of systemic disease. We aimed to investigate if disturbing the oral microbiota would impact the lower gut microbiome with functional effects in diet-induced obesity. Mice were exposed to oral chlorhexidine and fed a Western diet (WD). Food intake and weight gain were monitored, and metabolic function, blood pressure, and microbiota were analyzed. Chlorhexidine reduced the number of viable bacteria in the mouth and lowered species richness in the gut but with proportional enrichment of some bacteria linked to metabolic pathways. In mice fed a Western diet, chlorhexidine reduced weight gain, body fat, steatosis, and plasma insulin without changing caloric intake, while increasing colon triglycerides and proteins, suggesting reduced absorption of these nutrients. The mechanisms behind these effects as well as the link between the oral microbiome and small intestinal function need to be pinpointed. While the short-term effects of chlorhexidine in this model appear beneficial, potential long-term disruptions in the oral and gut microbiota and possible malabsorption should be considered.

Dicarbonyl compounds are highly reactive precursors of Advanced Glycation End-products (AGEs), produced endogenously, present in certain foods, and formed during food processing. AGEs contribute to development of adverse metabolic outcomes but health effects of dietary dicarbonyls are largely unexplored. We investigated associations between three dietary dicarbonyl compounds, methylglyoxal (MGO), glyoxal (GO), and 3-deoxyglucosone (3-DG), and body-weight changes in European adults. Dicarbonyl intakes were estimated using food composition database from 263,095 EPIC-PANACEA participants with two body-weight assessments (median follow-up time=5.4y). Associations between dicarbonyls and 5-year body-weight changes were estimated using mixed linear regression models. Stratified analyses by sex, age, and baseline BMI were performed. Risk of becoming overweight/obese was assessed using multivariable-adjusted logistic regression. MGO intake was associated with 5-year body-weight gain of 0.089kg (per 1-SD increase, 95%CI=0.072, 0.107). 3-DG was inversely associated with body-weight change (-0.076kg, -0.094, -0.058). No significant association was observed for GO (0.018kg, -0.002, 0.037). In stratified analyses, GO was associated with body-weight gain among women and older participants (above median of 52.4y). MGO was associated with higher body-weight gain among older participants. 3-DG was inversely associated with body-weight gain among younger and normal-weight participants. MGO was associated with higher risk of becoming overweight/obese, while inverse associations were observed for 3-DG. No associations were observed for GO with overweight/obesity. Dietary dicarbonyls are inconsistently associated with body-weight change among European adults. Further research is needed to clarify the role of these food components in overweight and obesity, their underlying mechanisms, and potential public-health implications.

Background: Childhood caries and obesity are complex chronic diseases with negative health outcomes.

Aim: This study sought a risk profile for childhood caries and overweight.

Design: Children were recruited into a longitudinal prospective cohort study. Caries and overweight characteristics were obtained at baseline, 6, 12, and 18 months. Sequential data modeling steps determined a disease risk profile.

Results: At baseline, 50% of the children (n = 194, 3.0 to 6.9 years) had caries; 24% were overweight, of whom 50% had caries. Correlation analysis separated child characteristics from household circumstances. Principal component modeling separated child snacking from meal-eating patterns, and household smoking from parent education variables. Baseline caries and overweight were not associated, but they grouped together in the modeling of composite features. Forty-five percent of children showed caries progression, 29% overweight progression, and 10% progression of both diseases. The strongest predictors of progression were disease presence, household-based characteristics, and sugary drinks. Children with caries and overweight progression shared multiple child- and household-based features.

Conclusion: Individually, caries and overweight were not associated. Children with progression of both conditions shared a profile and multiple risk characteristics suggesting these findings could be useful in assessing the risk for the most extreme cases of caries and overweight.

Aim: To evaluate the protein profiles in gingival crevicular fluid (GCF) in relation to clinical outcomes after periodontal surgery and examine if any selected proteins affect the mRNA expression of pro-inflammatory cytokines in human gingival fibroblasts.

Materials and Methods: This exploratory study included 21 consecutive patients with periodontitis. GCF was collected, and the protein pattern (n = 92) and clinical parameters were evaluated prior to surgery and 3, 6 and 12 months after surgery. Fibroblastic gene expression was analysed by real-time quantitative polymerase chain reaction.

Results: Surgical treatment reduced periodontal pocket depth (PPD) and changed the GCF protein pattern. Twelve months after surgery, 17% of the pockets showed an increase in PPD. Levels of a number of proteins in the GCF decreased after surgical treatment but increased with early signs of tissue destruction, with LIGHT being one of the proteins that showed the strongest association. Furthermore, LIGHT up-regulated the mRNA expression of pro-inflammatory cytokines interleukin (IL)-6, IL-8 and MMP9 in human gingival fibroblasts.

Conclusions: LIGHT can potentially detect subjects at high risk of periodontitis recurrence after surgical treatment. Moreover, LIGHT induces the expression of inflammatory cytokines and tissue-degrading enzymes in gingival fibroblasts.

Molecular characterization of the oral microbiome is a crucial first step in experiments which aim to understand the complex dynamics of the oral microbiome or the interplay with host health and disease. Third-generation Oxford Nanopore Technology (ONT) offers advanced long-read sequencing capabilities, which hold promise for improved molecular characterization by distinguishing closely related microbial species within oral ecosystems in health and disease states. However, the performance of ONT sequencing of oral samples requires validation, and the consistency of this approach across different analytical and sampling conditions is not well understood. This study evaluates various factors that may influence the ONT sequencing outputs of saliva microbiota and compares results with those from Illumina MiSeq's v3v4 amplicon sequencing. Our analysis includes assessments of various stages in the workflow, including different collection and extraction methods, such as robot-extracted saliva DNA used in population-based biobanks, the effects of limited DNA quantities, different bioinformatics pipelines, and different 16S rRNA gene databases. The results demonstrate that ONT provides superior resolution in identifying oral species and subspecies compared to Illumina MiSeq, though the choice of bioinformatics strategy significantly affects the outcomes. Additionally, we confirm the suitability of biobank saliva DNA for large-scale cohort studies, which facilitates the mapping of oral bacterial phylotypes associated with disease states, including less prevalent conditions. Overall, our findings confirm a markedly improved resolution of oral microbiomes by ONT and offer an evidence base to guide the conduct of experiments using this method.

Background: Knowledge about the variability of gut microbiota within an individual over time is important to allow meaningful investigations of the gut microbiota in relation to diet and health outcomes in observational studies. Plant-based dietary patterns have been associated with a lower risk of morbidity and mortality and may alter gut microbiota in a favorable direction.

Objectives: To assess the gut microbiota variability during one year and investigate the association between adherence to diet indexes and the gut microbiota in a Danish population.

Methods: Four hundred forty-four participants were included in the Diet, Cancer, and Health - Next Generations MAX study (DCH-NG MAX). Stool samples collected up to three times during a year were analyzed by 16S ribosomal ribonucleic acid gene sequencing. Diet was obtained by 24-hour dietary recalls. Intraclass correlation coefficient (ICC) was calculated to assess temporal microbial variability based on 214 individuals. Diet indexes (Nordic, Mediterranean, and plant-based diets) and food groups thereof were associated with gut microbiota using linear regression analyses.

Results: We found that 91 out of 234 genera had an ICC >0.5. We identified three subgroups dominated by Bacteroides, Prevotella 9, and Ruminococcaceae and adherence to diet indexes differed between subgroups. Higher adherence to diet indexes was associated with the relative abundance of 22 genera. Across diet indexes, higher intakes of fruit, vegetables, whole grains/cereals, and nuts were most frequently associated with these genera.

Conclusions: In the DCH-NG MAX study, 39% of the genera had an ICC >0.5 over one year, suggesting that these genera could be studied with health outcomes in prospective analyses with acceptable precision. Adherence to the Nordic, Mediterranean, and plant-based diets differed between bacterial subgroups and was associated with a higher abundance of genera with fiber-degrading properties. Fruits, vegetables, whole grains/cereals, and nuts were frequently associated with these genera.

The sequalae of periodontitis include irreversible degradation of tooth-supporting structures and circulatory spread of inflammatory mediators. However, the serum protein profile in periodontitis is not well described, which is partly attributable to the limited number of studies based on large and well-characterized periodontitis cohorts. This study aims to identify novel, circulating inflammation-related proteins associated with periodontitis within the PerioGene North case-control study, which includes 478 cases with severe periodontitis and 509 periodontally healthy controls. The serum concentrations of high-sensitivity C-reactive protein (hs-CRP) and a panel of 45 inflammation-related proteins were analyzed using targeted proteomics. A distinguishable serum protein profile was evident in periodontitis cases. The protein pattern could separate cases from controls with a sensitivity of 0.81 and specificity of 0.81 (area under the curve = 0.87). Adjusted levels for hs-CRP and 24 of the 45 proteins were different between cases and controls. High levels of hs-CRP and matrix metalloproteinase–12, and low levels of epidermal growth factor (EGF) and oxidized low-density lipoprotein receptor 1 (OLR-1) were detected among the cases. Furthermore, the levels of C-C motif chemokine–19, granulocyte colony-stimulating factor–3 (CSF-3), interleukin-7 (IL-7), and hs-CRP were significantly higher in cases with a high degree of gingival inflammation. The levels of CSF-3 and tumor necrosis factor ligand superfamily member–10 TNFSF-10 were higher in cases with many deep periodontal pockets. The PerioGene North study includes detailed clinical periodontal data and uncovers a distinct serum protein profile in periodontitis. The findings of lower EGF and OLR-1 among the cases are highlighted, as this has not been presented before. The role of EGF and OLR-1 in periodontitis pathogenesis and as possible future biomarkers should be further explored.