Periodontitis and risk of immune-mediated systemic conditions: A systematic review and meta-analysis

Quercetin through miR-147-5p/Clip3 axis reducing Th17 cell differentiation to alleviate periodontitis

Background

Quercetin (QU) plays an important role in treating periodontitis; however, the mechanism through which microRNAs regulate Th17 cell differentiation has not been determined.

Methods

QU was administered intragastrically to periodontitis rats once a day for one month. The morphology of alveolar bone was observed by micro-CT, gingival tissue structure was observed by HE staining, IL-6, TNF-α, IL-17A, RORγt, FOXP3 and IL-10 were detected by immunohistochemical staining, and Th17 and Treg cells in the peripheral blood were detected by flow cytometry. CD4+T cells were induced to differentiate into Th17 cells in vitro. Cell viability was determined by CCK8, and IL-17A and RORγt were detected by qPCR. Th17 cells were detected by flow cytometry, microRNA sequencing and bioinformatics analysis were used to screen key microRNAs, the phenotypic changes of Th17 cells were observed after overexpressed microRNAs via mimics. TargetScan database, in situ hybridization, and dual-luciferase reporter experiment were used to predict and prove target genes of microRNAs. The phenotype of Th17 cells was observed after overexpression of microRNA and target gene.

Results

Compared with periodontitis group, the distance from cementoenamel junction(CEJ) to alveolar bone(AB) was decreased, the structure of gingival papilla was improved, IL-6, TNF-α, IL-17, and RORγt were downregulated, FOXP3 and IL-10 were upregulated, the proportion of Th17 decreased and Treg increased in peripheral blood after QU treatment. Compared with Th17 cell group, mRNA levels of IL-17A and RORγt were decreased, and proportion of Th17 cells was significantly lower in the coculture group. MiR-147-5p was low in control group, upregulated in Th17 cell group, and downregulated after QU intervention, it's eight bases were inversely related to 3'UTR of Clip3, miR-147-5p with Clip3 were co-located in cells of periodontal tissue. Compared with those in Th17-mimicsNC + QU cells, the mRNA levels of RORγt and IL-17A upregulated, and proportion of Th17 cells increased in Th17-miR-147-5p + QU cells. The miR-147-5p mimics inhibited the luciferase activity of the WT Clip3 3'UTR but had no effect on the Mut Clip3 3'UTR. Clip3 was significantly downregulated after the overexpression of miR-147-5p. Mimics transfected with miR-147-5p reversed the decrease in the proportion of Th17 cells induced by QU, while the overexpression of Clip3 antagonized the effect of miR-147-5p and further reduced the proportion of Th17 cells. Moreover, the overexpression of miR-147-5p reversed the decreases in the mRNA levels of IL-17 and RORγt induced by QU treatment, while pcDNA3.1 Clip3 treatment further decreased the mRNA levels of IL-17 and RORγt.

Conclusion

QU reducing inflammatory response and promoting alveolar bone injury and repair, which closely relative to inhibit the differentiation of CD4+T cells into Th17 cells by downregulating miR-147-5p to promote the activation of Clip3.

Using SWATH-MS to identify new molecular biomarkers in gingival crevicular fluid for detecting periodontitis and its response to treatment

AIM

To identify new biomarkers to detect untreated and treated periodontitis in gingival crevicular fluid (GCF) using sequential window acquisition of all theoretical mass spectra (SWATH-MS).

MATERIALS AND METHODS

GCF samples were collected from 44 periodontally healthy subjects and 40 with periodontitis (Stages III-IV). In the latter, 25 improved clinically 2 months after treatment. Samples were analysed using SWATH-MS, and proteins were identified by the UniProt human-specific database. The diagnostic capability of the proteins was determined with generalized additive models to distinguish the three clinical conditions.

RESULTS

In the untreated periodontitis vs. periodontal health modelling, five proteins showed excellent or good bias-corrected (bc)-sensitivity/bc-specificity values of >80%. These were GAPDH, ZG16B, carbonic anhydrase 1, plasma protease inhibitor C1 and haemoglobin subunit beta. GAPDH with MMP-9, MMP-8, zinc-α-2-glycoprotein and neutrophil gelatinase-associated lipocalin and ZG16B with cornulin provided increased bc-sensitivity/bc-specificity of >95%. For distinguishing treated periodontitis vs. periodontal health, most of these proteins and their combinations revealed a predictive ability similar to previous modelling. No model obtained relevant results to differentiate between periodontitis conditions.

CONCLUSIONS

New single and dual GCF protein biomarkers showed outstanding results in discriminating untreated and treated periodontitis from periodontal health. Periodontitis conditions were indistinguishable. Future research must validate these findings.

A randomised controlled trial to evaluate the effectiveness of personalised oral hygiene advice delivered via video technology

OBJECTIVES

To determine whether video-technology oral hygiene advice (OHA) improved clinical plaque and bleeding on probing (BOP) scores in individuals diagnosed with gingivitis, compared to conventional OHA after 3-months.

METHODS

This parallel, randomised 2-arm treatment, single-centre study, assessed Turesky Plaque Index (TPI) and BOP at baseline and 3-months in adult participants with mild-moderate gingivitis. Eligible participants with smartphones were randomised at baseline to intervention (tailored video OHA), or control (conventional OHA). Oral hygiene (OH) habits/attitudes were recorded with a questionnaire. All participants used a manual toothbrush with anti-gingivitis toothpaste twice daily.

RESULTS

57 participants completed the study. Both groups had improved gingival health (BOP) after 3-months, change from baseline being significantly greater in the intervention group (12.21% vs 6.80 %, p < 0.05). TPI scores decreased more in the intervention than control group, but the difference did not reach significance (1.15 vs 0.92, p = 0.079). OH habits and attitudes were similar at baseline and few differences between the groups were observed after 3-months, however frequency of interdental brush use was significantly increased, while self-rated oral health was significantly decreased in the intervention as compared to control group at this timepoint (p < 0.05).

CONCLUSIONS

The combination of an individually tailored instructional video with appropriate toothbrushing using anti-gingivitis toothpaste and interdental brush, significantly improved participants' gingival health over 3-months compared to brushing with an anti-gingivitis toothpaste with conventional OHA as delivered in the general dental services. This study demonstrates the benefit of changing OH behaviour and delivering OHA using an individually tailored approach with contemporary methodology.

CLINICAL SIGNIFICANCE

OHA is usually verbally delivered over short time periods. This study demonstrates video technology with individualised OHA improves OH adherence and empowers individuals, the recipient receiving personal visual cues with ability to replay advice and technique reiteration. This real-world technology could be better utilised in general dental practice.

The Molecular Comorbidity Network of Periodontal Disease

Periodontal disease, a multifactorial inflammatory condition affecting the supporting structures of the teeth, has been increasingly recognized for its association with various systemic diseases. Understanding the molecular comorbidities of periodontal disease is crucial for elucidating shared pathogenic mechanisms and potential therapeutic targets. In this study, we conducted comprehensive literature and biological database mining by utilizing DisGeNET2R for extracting gene-disease associations, Romin for integrating and modeling molecular interaction networks, and Rentrez R libraries for accessing and retrieving relevant information from NCBI databases. This integrative bioinformatics approach enabled us to systematically identify diseases sharing associated genes, proteins, or molecular pathways with periodontitis. Our analysis revealed significant molecular overlaps between periodontal disease and several systemic conditions, including cardiovascular diseases, diabetes mellitus, rheumatoid arthritis, and inflammatory bowel diseases. Shared molecular mechanisms implicated in the pathogenesis of these diseases and periodontitis encompassed dysregulation of inflammatory mediators, immune response pathways, oxidative stress pathways, and alterations in the extracellular matrix. Furthermore, network analysis unveiled the key hub genes and proteins (such as TNF, IL6, PTGS2, IL10, NOS3, IL1B, VEGFA, BCL2, STAT3, LEP and TP53) that play pivotal roles in the crosstalk between periodontal disease and its comorbidities, offering potential targets for therapeutic intervention. Insights gained from this integrative approach shed light on the intricate interplay between periodontal health and systemic well-being, emphasizing the importance of interdisciplinary collaboration in developing personalized treatment strategies for patients with periodontal disease and associated comorbidities.

Exploring the Bidirectional Relationship Between Periodontitis and Rheumatoid Arthritis in a Large Danish Cohort

OBJECTIVE

We investigated the bidirectional relationship between rheumatoid arthritis (RA) and periodontitis and their cross-sectional association using national administrative health care data.

METHODS

The sample included 3,308,903 individuals aged 20 to 79 years who resided in Denmark in 2000 and had remained free of RA and periodontitis in the previous 10 years. RA and periodontitis were defined using diagnosis and treatment codes. Marginal structural survival models were employed to estimate the effects of RA on periodontitis incidence and vice versa from 2000 to 2017. Using a cross-sectional sample of 2,574,536 individuals from 2017, the association of periodontitis with RA was investigated using regression analyses and probabilistic quantitative bias analyses, simulating RA and periodontitis misclassification and unmeasured confounding of smoking.

RESULTS

Between 2000 and 2017, 20,348 individuals developed RA and 740,799 developed periodontitis. The estimated hazard ratio (HR) for the effect of periodontitis on incident RA was 1.05 (95% confidence interval [CI] 0.88-1.25), resulting in a restricted mean survival time difference of one day. The HR for the effect of RA on incident periodontitis was 0.84 (95% CI 0.80-0.88), corresponding to a restricted mean survival time difference of 151 days. Cross-sectionally, the unadjusted prevalence ratio for the association was 1.15 (95% CI 1.11-1.19), whereas the estimate adjusted for measured and simulated confounding was practically null (0.99, 95% simulation interval 0.93-1.04).

CONCLUSION

These findings challenge previously reported bidirectional relationships between periodontitis and RA, pointing to potential residual confounding as an important link and prompting reconsideration of the biologic plausibility and clinical significance of these associations.

All-cause and cause-specific mortality in US adults with periodontal diseases: A prospective cohort study

AIM

This prospective cohort study investigated the association between periodontal diseases (PDs) and all-cause and cause-specific mortality.

MATERIALS AND METHODS

We utilized adult participants recruited from six National Health and Nutrition Examination Survey cycles (1999-2014) and linked mortality data from the National Death Index up to December 2019. Baseline clinical periodontal examinations were performed by trained and calibrated examiners. All-cause and cause-specific mortality was modelled through multivariable Cox proportional hazards and Fine-Gray models to account for competing risks. All models were adjusted for demographic and lifestyle variables, clinical measurements and comorbidities.

RESULTS

Overall, 15,030 participants were included, with a median length of follow-up of 9 years. Risk of all-cause mortality was 22% greater in people with PD than the control group (adjusted hazard ratio [HR]: 1.22, 95% confidence interval [CI]: 1.12-1.31). Risks of mortality by cardiovascular diseases (CVD), respiratory disease and diabetes were highest in participants with severe PD (CVD-sub-distribution HR [SHR]: 1.38, 95% CI: 1.16-1.64; respiratory-SHR: 1.62, 95% CI: 1.07-2.45; diabetes-SHR: 1.68, 95% CI: 1.12-2.53).

CONCLUSIONS

Severe PD is associated with all-cause and cause-specific mortality among US adults after multivariable adjustment.

Oral diseases are associated with cognitive function in adults over 60 years old

OBJECTIVE

To investigate the bidirectional association between oral diseases and cognitive function comprehensively.

SUBJECTS AND METHODS

This cross sectional study utilized data from the National Health and Nutrition Examination Survey. Oral diseases include periodontitis, dental caries, and tooth loss (end point of oral disease resulting in tooth extraction). Cognitive function included three domains: memory, processing speed, and executive function. A global cognitive score was then derived from sum of the three cognitive domains. Oral cognition associations were examined using various statistical models: (1) Regress oral disease on cognitive function; (2) Regress cognitive function on oral disease; and (3) Structural equation modelling treating cognition and oral disease as latent variables.

RESULTS

There were 2508 participants aged 60+ who had both oral and cognitive information. Associations between various oral disease and global cognitive score were observed (Odds ratio ORcog->periodontitis 0.95, 95% Confidence Interval [0.92, 0.99]; βcog->caries -0.13, [-0.23, -0.04]; βcog->tooth loss -0.03 [-0.04, -0.01]; βtooth loss->cog -0.04 [-0.06, -0.02]; βcaries->cog -0.03 [-0.06, -0.01]; βperiodontitis->cog -0.39 [-0.69, -0.10]). Significant correlation was also found between these oral disease and cognitive function using structural equation model (r -0.22, [-0.34, -0.10]).

CONCLUSIONS

This study found robust bidirectional associations between oral disease and cognitive function using various modelling approaches among the aging population.

Impact of Non-Surgical Periodontal Treatment on the Concentration and Level of MRP-8/14 (Calprotectin) as an Inflammatory Biomarker in Women with Periodontitis and Rheumatoid Arthritis: A Quasi-Experimental Study

The aim of this study was to evaluate the impact of non-surgical periodontal treatment (NS-PT) on periodontal parameters and inflammatory biomarkers in the concentration and level of calprotectin (CLP) in women with periodontitis and rheumatoid arthritis (RA). In this quasi-experimental study, we evaluated 30 women (mean age: 52.0 ± 5.8 years) with periodontitis and RA who had been diagnosed and treated for RA for more than 3 years and whose activity markers remained at similar values without significant reduction over three consecutive months. Patients underwent NS-PT, which included plaque control, scaling, and root planing. Serum and saliva samples, periodontal indices, RA activity markers, Disease Activity Score-28 (DAS28), the erythrocyte sedimentation rate (ESR), and the C-reactive protein (CRP) and CLP contents were measured at the beginning of the study and 6 and 12 weeks after NS-PT. Parametric and nonparametric tests were used in the analysis. The mean age was 52.0 ± 5.8 years. Compared to the baseline results, all periodontal indices were significantly reduced 6 and 12 weeks after NS-PT (p < 0.001). DAS28 was also significantly reduced after 12 weeks (p < 0.0001). Similarly, the serum CLP concentration decreased 6 and 12 weeks after NS-PT (p < 0.0001). Of the patients, 100% presented lower levels of CRP and ESR (p < 0.0001). Overall, NS-PT reduced inflammation and disease activity, highlighting the importance of oral health in the control and treatment of systemic diseases such as RA and confirming that NS-PT effectively reduces periodontitis activity and plays a key role in modulating RA activity. Therefore, NS-PT should be considered as an adjunct treatment for RA.

Ligneous periodontitis exacerbated by Behçet's disease in a patient with plasminogen deficiency and a stop-gained variant PLG c.1468C > T: a case report

BACKGROUND

Plasminogen serves as the precursor to plasmin, an essential element in the fibrinolytic process, and is synthesized primarily in the liver. Plasminogen activation occurs through the action of plasminogen activator, converting it into plasmin. This conversion greatly enhances the fibrinolytic system within tissues and blood vessels, facilitating the dissolution of fibrin clots. Consequently, congenital deficiency of plasminogen results in impaired fibrin degradation. Patients with plasminogen deficiency typically exhibit fibrin deposits in various mucosal sites throughout the body, including the oral cavity, eyes, vagina, and digestive organs. Behcet's disease is a chronic recurrent systemic inflammatory disease with four main symptoms: aphthous ulcers of the oral mucosa, vulvar ulcers, skin symptoms, and eye symptoms, and has been reported worldwide. This disease is highly prevalent around the Silk Road from the Mediterranean to East Asia. We report a case of periodontitis in a patient with these two rare diseases that worsened quickly, leading to alveolar bone destruction. Genetic testing revealed a novel variant characterized by a stop-gain mutation, which may be a previously unidentified etiologic gene associated with decreased plasminogen activity.

CASE PRESENTATION

This case report depicts a patient diagnosed with ligneous gingivitis during childhood, originating from plasminogen deficiency and progressing to periodontitis. Genetic testing revealed a suspected association with the PLG c.1468C > T (p.Arg490*) stop-gain mutation. The patient's periodontal condition remained stable with brief intervals of supportive periodontal therapy. However, the emergence of Behçet's disease induced acute systemic inflammation, necessitating hospitalization and treatment with steroids. During hospitalization, the dental approach focused on maintaining oral hygiene and alleviating contact-related pain. The patient's overall health improved with inpatient care and the periodontal tissues deteriorated.

CONCLUSIONS

Collaborative efforts between medical and dental professionals are paramount in comprehensively evaluating and treating patients with intricate complications from rare diseases. Furthermore, the PLG c.1468C > T (p.Arg490*) stop-gain mutation could contribute to the association between plasminogen deficiency and related conditions.

Potential Clinical Application of Organs-on-a-Chip in Periodontal Diseases: A Systematic Review of In Vitro Studies

The periodontium is a unique organ from the standpoint of building an organ-on-a-chip (OoC) since it is a system that is continually threatened by microorganisms, their noxious compounds, and antigenic components. At the same time, periodontal health depends on a balanced connection between the host and the bacteria in the oral cavity, which is a complex micro-ecological environment. The objective of this systematic review of in vitro studies is to revise the potential clinical application of OoC in periodontal diseases. PRISMA was used to guide this analysis. The review framework made use of several databases, including SCOPUS, PubMed/MEDLINE, SCIELO, and LILACS as well as the gray literature. This systematic review comprised seven studies. The clinical efficacy of OoC in periodontal diseases was observed in models of the gingival crevice for the research of periodontitis, periodontal medication analysis, the interaction of multiple microbial species, pH measurements in in situ-grown biofilm, testing antimicrobial reagents, evaluation of mucosal interactions with microorganisms, and a device for quantitative exploration of microorganisms. OoC has the potential to advance our understanding of periodontal diseases by providing a more accurate representation of the oral microenvironment and enabling the development of new treatments.

Oral-Gut Microbiota, Periodontal Diseases, and Arthritis: Literature Overview on the Role of Probiotics

Periodontal diseases are oral inflammatory diseases affecting the tissues supporting and surrounding the teeth and include gingivitis and periodontitis. Oral pathogens may lead to microbial products spreading into the systemic circulation and reaching distant organs, while periodontal diseases have been related to low-grade systemic inflammation. Gut and oral microbiota alterations might play a role in the pathogenesis of several autoimmune and inflammatory diseases including arthritis, considering the role of the gut-joint axis in the regulation of molecular pathways involved in the pathogenesis of these conditions. In this scenario, it is hypothesized that probiotics might contribute to the oral and intestinal micro-ecological balance and could reduce low-grade inflammation typical of periodontal diseases and arthritis. This literature overview aims to summarize state-of-the-art ideas about linkages among oral-gut microbiota, periodontal diseases, and arthritis, while investigating the role of probiotics as a potential therapeutic intervention for the management of both oral diseases and musculoskeletal disorders.

Identification of Nutritional Factors to Evaluate Periodontal Clinical Parameters in Patients with Systemic Diseases

Nutritional factors reflect the periodontal parameters accompanying periodontal status. In this study, the associations between nutritional factors, blood biochemical items, and clinical parameters were examined in patients with systemic diseases. The study participants were 94 patients with heart disease, dyslipidemia, kidney disease, or diabetes mellitus. Weak negative correlation coefficients were found between nine clinical parameters and ten nutritional factors. Stage, grade, mean probing depth (PD), rate of PD 4−5 mm, rate of PD ≥ 6 mm, mean clinical attachment level (CAL), and the bleeding on probing (BOP) rate were weakly correlated with various nutritional factors. The clinical parameters with coefficients of determinations (R2) > 0.1 were grade, number of teeth, PD, rate of PD 4−5 mm, CAL, and BOP rate. PD was explained by yogurt and cabbage with statistically significant standardized partial regression coefficients (yogurt: −0.2143; cabbage and napa cabbage: −0.2724). The mean CAL was explained by pork, beef, mutton, and dark green vegetables with statistically significant standardized partial regression coefficients (−0.2237 for pork, beef, and mutton; −0.2667 for dark green vegetables). These results raise the possibility that the frequency of intake of various vegetables can be used to evaluate periodontal stabilization in patients with systemic diseases.

The effect of the "Oral-Gut" axis on periodontitis in inflammatory bowel disease: A review of microbe and immune mechanism associations

Periodontitis and inflammatory bowel diseases (IBD) are inflammatory diseases of the gastrointestinal tract that share common features of microbial-induced ecological dysregulation and host immune inflammatory response. The close relationship between periodontitis and IBD is characterized by a higher prevalence of IBD in patients with periodontitis and a higher prevalence and severity of periodontitis in patients with IBD, indicating that periodontitis and IBD are different from the traditional independent diseases and form an "Oral-Gut" axis between the two, which affect each other and thus form a vicious circle. However, the specific mechanisms leading to the association between the two are not fully understood. In this article, we describe the interconnection between periodontitis and IBD in terms of microbial pathogenesis and immune dysregulation, including the ectopic colonization of the gut by pathogenic bacteria associated with periodontitis that promotes inflammation in the gut by activating the host immune response, and the alteration of the oral microbiota due to IBD that affects the periodontal inflammatory response. Among the microbial factors, pathogenic bacteria such as Klebsiella, Porphyromonas gingivalis and Fusobacterium nucleatum may act as the microbial bridge between periodontitis and IBD, while among the immune mechanisms, Th17 cell responses and the secreted pro-inflammatory factors IL-1β, IL-6 and TNF-α play a key role in the development of both diseases. This suggests that in future studies, we can look for targets in the "Oral-Gut" axis to control and intervene in periodontal inflammation by regulating periodontal or intestinal flora through immunological methods.