Epidemiological associations between periodontitis and cancer

There is a postulated association of periodontitis with a number of human cancers. This narrative review provides current epidemiological evidence on the association between periodontitis and cancer. A PubMed search with the relevant keywords (periodontal disease, periodontitis, cancer, and malignancy) was completed to identify relevent articles. We present a narrative review on the association between periodontal disease and a range of cancers, including oral cancer, stomach and esophageal cancer, colorectal cancer, lung cancer, pancreatic cancer, prostate cancer, hematological malignancies, liver cancer, breast cancer, and ovarian cancer. While there is a considerable body of epidemiological evidence that supports the association between periodontal disease and cancer, this is largely from cohort and case-control studies and the association may therefore be circumstantial as little evidence exists in the form of treatment trials that would validate the role of periodontal disease in the process of cancer initiation and development.

The Role of Interleukin-8 in the Estimation of Responsiveness to Steps 1 and 2 of Periodontal Therapy

OBJECTIVE

To investigate the association between interleukin-8 (IL-8) levels in gingival crevicular fluid (GCF) and total oral fluid (TOF) and the responsiveness to steps 1 and 2 of periodontal therapy.

MATERIALS AND METHODS

One-hundred and fifty-nine patients affected by periodontitis received steps 1 and 2 of periodontal therapy. At baseline, TOF and GCF samples were collected and analysed for IL-8 (Il-8TOF/IL-8GCF) using flow cytometry. Therapy outcomes were relative proportions of residual periodontal pockets (PPD%), pocket closure (PC) rates and pocket probing depth (PPD) reductions; these were associated with IL-8TOF/IL-8GCF.

RESULTS

High IL-8TOF was significantly associated with higher residual PPD% (p = 0.044) and lower PPD reduction compared to low IL-8TOF (high 0.79 ± 1.20 mm vs. low 1.20 ± 1.20 mm, p < 0.001) in non-smokers, while in smokers high IL-8GCF was related to lower PPD reduction (high 0.62 ± 1.22 mm vs. low 0.84 ± 1.12 mm, p = 0.009). Furthermore, high baseline IL-8TOF was significantly associated with poorer PC rates compared to medium and low concentrations in both non-smokers (high 41% vs. medium 55% vs. low 58%, p < 0.001) and smokers (high 34% vs. medium 44% vs. low 46%, p < 0.001).

CONCLUSION

High IL-8 concentrations at baseline had a significant impact on residual PPD%, PC rates and PPD reduction. The findings suggest that, especially in non-smokers, baseline IL-8 levels collected from the TOF could serve as a component in the estimation of responsiveness to steps 1 and 2 of periodontal therapy.

Association of the Life's Essential 8 cardiovascular health score with periodontitis among US adults

AIM

To investigate whether cardiovascular health (CVH) is associated with periodontitis.

MATERIALS AND METHODS

We used data from the 2009 to 2014 National Health and Nutrition Examination Survey. We quantified CVH using Life's Essential 8, which includes four health behaviours (diet, smoking, physical activity and sleep) and four health factors (body mass index, blood cholesterol, glucose and pressure). We categorized scores as low (0-49), moderate (50-79) and high (80-100). We calculated subscores of health behaviours and factors and categorized them as low, moderate and high. We used logistic regression to assess the association of CVH with periodontitis, adjusting for age, gender, race/ethnicity, education, poverty index, marital status and health insurance. We computed odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

This study included 9296 adults ≥30 years old. Multivariable-adjusted models showed that subjects with moderate (OR, 0.62; 95% CI: 0.52-0.74) or high (OR, 0.43; 95% CI: 0.33-0.57) CVH had significantly lower odds of periodontitis compared to those with low CVH. These results were consistent in the health behaviours model, but the estimates in the health factors model were not significant.

CONCLUSIONS

Improving CVH may help prevent periodontitis. Longitudinal studies are needed to confirm our findings.

Serum vitamin D, hemoglobin A1c and vitamin B12 levels in patients with gingivitis and periodontitis stages

Aim: To compare the serum vitamin D, hemoglobin A1c (HbA1c) and vitamin B12 levels in patients with gingivitis and four different periodontitis stages diagnosed according to the 2017 Periodontal Disease Classification. Materials & methods: A total of 606 patients were included in the study who were diagnosed with gingivitis and stage I-IV periodontitis. Patients were divided into groups based on disease stage, and the HbA1c, vitamin D and B12 levels of the patients were compared and analyzed. Result: The highest HbA1c level and the lowest vitamin D level were seen in stage III-IV periodontitis. The highest vitamin D and B12 levels were seen in the gingivitis group. Conclusion: Serum HbA1c, vitamin D and B12 levels might vary depending on the presence or severity of periodontitis.Clinical Trial Registration: NCT05745779 (This study was registered and approved by www.clinicaltrials.gov).

No genetic causal associations between periodontitis and brain atrophy or cognitive impairment: evidence from a comprehensive bidirectional Mendelian randomization study

BACKGROUND

Observational studies have explored the relationships of periodontitis with brain atrophy and cognitive impairment, but these findings are limited by reverse causation, confounders and have reported conflicting results. Our study aimed to investigate the causal associations of periodontitis with brain atrophy and cognitive impairment through a comprehensive bidirectional Mendelian randomization (MR) research.

METHODS

We incorporated two distinct genome-wide association study (GWAS) summary datasets as an exploration cohort and a replication cohort for periodontitis. Four and eight metrics were selected for the insightful evaluation of brain atrophy and cognitive impairment, respectively. The former involved cortical thickness and surface area, left and right hippocampal volumes, with the latter covering assessments of cognitive performance, fluid intelligence scores, prospective memory, and reaction time for mild cognitive impairment to Alzheimer's disease (AD), Lewy body dementia, vascular dementia and frontotemporal dementia for severe situations. Furthermore, supplementary analyses were conducted to examine the associations between the longitudinal rates of change in brain atrophy and cognitive function metrics with periodontitis. The main analysis utilized the inverse variance weighting (IVW) method and evaluated the robustness of the results through a series of sensitivity analyses. For multiple tests, associations with p-values < 0.0021 were considered statistically significant, while p-values ≥ 0.0021 and < 0.05 were regarded as suggestive of significance.

RESULTS

In the exploration cohort, forward and reverse MR results revealed no causal associations between periodontitis and brain atrophy or cognitive impairment, and only a potential causal association was found between AD and periodontitis (IVW: OR = 0.917, 95% CI from 0.845 to 0.995, P = 0.038). Results from the replication cohort similarly corroborated the absence of a causal relationship. In the supplementary analyses, the longitudinal rates of change in brain atrophy and cognitive function were also not found to have causal relationships with periodontitis.

CONCLUSIONS

The MR analyses indicated a lack of substantial evidence for a causal connection between periodontitis and both brain atrophy and cognitive impairment.

Clinical applications and mechanism insights of natural flavonoids against type 2 diabetes mellitus

Diabetes is a complex disease that affects a large percentage of the world's population, and it is associated with several risk factors. Self-management poses a significant challenge, but natural sources have shown great potential in providing effective glucose reducing solutions. Flavonoids, a class of bioactive substances found in different natural sources including medicinal plants, have emerged as promising candidates in this regard. Indeed, several flavonoids, including apigenin, arbutin, catechins, and cyanidin, have demonstrated remarkable anti-diabetic properties. The clinical effectiveness of these flavonoids is linked to their potential to decrease blood glucose concentration and increase insulin concentration. Thus, the regulation of certain metabolic pathways such as glycolysis and neoglycogenesis has also been demonstrated. In vitro and in vivo investigations revealed different mechanisms of action related to flavonoid compounds at subcellular, cellular, and molecular levels. The main actions reside in the activation of glycolytic signaling pathways and the inhibition of signaling that promotes glucose synthesis and storage. In this review, we highlight the clinical efficiency of natural flavonoids as well as the molecular mechanisms underlying this effectiveness.

Hormone replacement therapy and periodontitis progression in postmenopausal women: A prospective cohort study

OBJECTIVE

This study aimed to investigate the responses of periodontal environment to hormone replacement therapy (HRT) in postmenopausal women with or without periodontitis.

BACKGROUND

HRT is a common and effective strategy for controlling menopausal symptoms, while the changes of periodontal environment under it, particularly in postmenopausal women with periodontitis, remain unclear.

METHODS

As a prospective cohort study, a total of 97 postmenopausal women receiving HRT were screened, including 47 with and 50 without periodontitis. Correspondingly, 97 women did not receiving HRT were screened as controls during the same period. The full-mouth sulcus bleeding index (SBI), bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL) were measured using periodontal probes. The levels of interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) in the gingival crevicular fluid were measured using enzyme-linked immunosorbent assay. In addition, cone beam computed tomography was performed to measure the alveolar bone height (ABH) and bone mineral density (BMD).

RESULTS

In postmenopausal women without periodontitis, no significantly changes on periodontal parameters were observed after HRT. In women with stage II periodontitis, SBI, BOP, IL-6, and TNF-α were significant decreased after one year and two years of HRT. Compared to the controls, women with stage II periodontitis who underwent HRT had significantly lower CAL and ABH and higher BMD in the second year. The incidence of at least one site with CAL increase ≥1 mm between baseline and 2 years was significantly lower in the HRT group than in the control group in women with stage II periodontitis. In addition, HRT was significantly associated with a decrease in SBI, BOP, IL-6, and TNF-α in the first year and with a decrease in CAL, SBI, BOP, IL-6, and ABH and an increase in BMD in the second year.

CONCLUSIONS

In postmenopausal women with stage II periodontitis, HRT is associated with the alleviation of inflammation within two years and the remission of alveolar bone loss in the second year. HRT appears to decrease the incidence of CAL increase ≥1 mm within 2 years in women with periodontitis by inhibiting inflammation and alveolar bone loss.

Association between blood ethylene oxide levels and periodontitis risk: a population-based study

Background

The etiopathogenesis of periodontitis is closely associated with environmental conditions. However, the relationship between ethylene oxide exposure and periodontitis risk remains unclear.

Methods

We selected qualified participants from National Health and Nutrition Examination Survey (NHANES) 2013-2014. Periodontitis was identified according to the criteria of the Community Periodontal Index (CPI), Centers for Disease Control and Prevention (CDC)/American Academy of Periodontology (AAP) definition. Ethylene oxide exposure was quantified by hemoglobin adducts of ethylene oxide (HbEO) levels. Log2-transformation was used to normalize HbEO levels. We designed three logistic regression models to explore potential relationship between HbEO and periodontitis. Restricted cubic spline (RCS) and subgroup analysis were also conducted with all covariates adjusted. We performed multivariable linear regression to appraise the association between the risk of periodontitis and different indicators of inflammation, including white blood cells, neutrophils, lymphocytes, and monocytes. Mediation analysis was subsequently performed to examine whether ethylene oxide exposure contributed to periodontitis development through systemic body inflammation.

Results

A total of 1,065 participants aged more than 30 were incorporated in this study. We identified that participants with higher HbEO levels showed increased risk of periodontitis after adjusting for all covariates (OR = 1.49, 95% CI: 1.14, 1.95, p = 0.0014). The results of subgroup analysis remained stable. The restricted cubic spline (RCS) curve also revealed a non-linear correlation between log2-transformed HbEO levels with the risk of periodontitis (p for nonlinear < 0.001). Mediation analysis indicated that HbEO level was significantly associated with four inflammatory mediators, with the mediated proportions of 14.44% (p < 0.001) for white blood cell, 9.62% (p < 0.001) for neutrophil, 6.17% (p = 0.006) for lymphocyte, and 6.72% (p < 0.001) for monocyte.

Conclusion

Participants with higher ethylene oxide exposure showed higher risk of periodontitis, which was partially mediated by systemic body inflammation. More well-designed longitudinal studies should be carried out to validate this relationship.

Clinical, immunological, and microbiological analysis of the association between periodontitis and COVID-19: a case-control study

PURPOSE

Periodontitis and coronavirus disease (COVID-19) share risk factors and activate similar immunopathological pathways, intensifying systemic inflammation. This study investigated the clinical, immunological and microbiological parameters in individuals with COVID-19 and controls, exploring whether periodontitis-driven inflammation contributes to worsening COVID-19 endpoints.

METHODS

Case (positive RT-PCR for SARS-CoV-2) and control (negative RT-PCR) individuals underwent clinical and periodontal assessments. Salivary levels of TNF-α, IL-6, IL-1β, IL-10, OPG, RANKL, neutrophil extracellular traps, and subgingival biofilm were analyzed at two timepoints. Data on COVID-19-related outcomes and comorbidity information were evaluated from medical records.

RESULTS

Ninety-nine cases of COVID-19 and 182 controls were included for analysis. Periodontitis was associated with more hospitalization (p = 0.009), more days in the intensive care unit (ICU) (p = 0.042), admission to the semi-ICU (p = 0.047), and greater need for oxygen therapy (p = 0.042). After adjustment for confounders, periodontitis resulted in a 1.13-fold increase in the chance of hospitalization. Salivary IL-6 levels (p = 0.010) were increased in individuals with COVID-19 and periodontitis. Periodontitis was associated with increased RANKL and IL-1β after COVID-19. No significant changes were observed in the bacterial loads of the periodontopathogens Porphyromona gingivalis, Aggregatibacter actinomycetemcomitans, Tanerella forsythia, and Treponema denticola.

CONCLUSIONS

Periodontitis was associated with worse COVID-19 outcomes, suggesting the relevance of periodontal care to reduce the burden of overall inflammation. Understanding the crosstalk between SARS-CoV-2 infection and chronic conditions such as periodontitis that can influence disease outcome is important to potentially prevent complications of COVID-19.

Periodontitis-resistant and -susceptible matriline regulation of gingival transcriptome in nonhuman primates

OBJECTIVE

This report identified if gingival gene expression transcriptomes demonstrated unique profiles that discriminated periodontitis-susceptible (PDS) and periodontitis-resistant (PDR) animals in health and disease.

BACKGROUND

Nonhuman primates generally organize their social groups based upon matriline origin. We have used a multi-generational colony of rhesus macaques to identify matrilines presenting with significant differences in periodontitis (e.g., earlier age onset, greater prevalence, and severity).

METHODS

Animals from 12 to 23 years of age (n = 17; 8 - PDR, 9 - PDS) were entered into a ligature-induced periodontitis trial. Gingival biopsies were taken at baseline and 0.5, 1, 3, and 5 months post-ligation, and microarray analysis was used to quantify gene expression in samples at each time point.

RESULTS

Over 1000 genes showed significant (p < .01) differences in the PDR versus PDS animals at baseline. The frequency of differences generally decreased during the disease process, and increased with resolution (i.e., 5 months). A nearly 2:1 ratio of elevated gene levels was noted in baseline PDR samples that included up-regulated MMPs, Fc receptors, chemokines, interleukins, and innate immune receptors, and down-regulated genes particularly related to epithelial biology. Most dramatically, there was a skewed differential expression of adaptive immune response genes in the PDR and epithelial cell structure/function genes in PDS samples.

CONCLUSIONS

The results demonstrate substantive differences in gingival tissue response capacity/programming in PDR and PDS samples that may contribute to the differences in clinical outcomes related to the heritability of disease risk through matrilines.

Comparison of immunoexpression of dendritic cells, mast cells and blood vessels in periodontal disease between adults and elderly

OBJECTIVE

The aim of this study was to compare, in adults and elderly individuals, the immunoexpression of immature and mature dendritic cells (DCs), mast cells, and blood vessels in healthy and diseased gingival tissues.

MATERIALS AND METHODS

The expressions of immunohistochemical markers, including CD1a (immature dendritic cells), CD83 (mature dendritic cells), tryptase (mast cells) and CD34 (blood vessels), were analyzed in gingival biopsies from elderly (n = 27) and adult (n = 127) patients presenting health, gingivitis and periodontitis. Positive cells for each specimen and marker were counted.

RESULTS

There were no differences in the immunostaining of DCs, mast cells and the amount of blood vessels among gingival biopsies with health, gingivitis and periodontitis in adult and elderly subjects (p > 0.05). Immature DCs were more frequent in tissues with gingivitis and periodontitis in elderly patients, when compared to adults (p < 0.05). Furthermore, degranulated mast cell counts were higher, whereas the number of microvessels was lower in gingivitis in the elderly, when compared to adults (p < 0.05).

CONCLUSIONS

Diseased periodontal sites in the elderly present an overall significant overexpression of immature DCs and degranulated mast cells, in relation to those of adults. Furthermore, gingivitis in elderly is associated with decreased microvessel growth. These immunoinflammatory differences between elderly and adults may have implications in periodontal tissue breakdown in the late adulthood. Further studies should be performed to elucidate this hypothesis.

CLINICAL RELEVANCE

Understading the relationship between aging and changes in immune cells during periodontal inflammation may lead to therapeutic targets for the future management of periodontal diseases.

Unraveling the Link between Periodontitis and Coronavirus Disease 2019: Exploring Pathogenic Pathways and Clinical Implications

Periodontitis involves the inflammation of the periodontal tissue, leading to tissue loss, while coronavirus disease 2019 (COVID-19) is a highly transmissible respiratory disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is amplified by poor systemic health. Key facilitators of SARS-CoV-2's entry into host cells are angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2). This review reveals that periodontal pockets can serve as a hotspot for virus accumulation, rendering surrounding epithelia more susceptible to infection. Given that ACE2 is expressed in oral mucosa, it is reasonable to suggest that poor periodontal health could increase the risk of COVID-19 infection. However, recent studies have not provided sufficient evidence to imply a significant effect of COVID-19 on periodontal health, necessitating further and more long-term investigations. Nevertheless, there are hypotheses linking the mechanisms of the two diseases, such as the involvement of interleukin-17 (IL-17). Elevated IL-17 levels are observed in both COVID-19 and periodontitis, leading to increased osteoclast activity and bone resorption. Lastly, bidirectional relationships between periodontitis and systemic diseases like diabetes are acknowledged. Given that COVID-19 symptoms may worsen with these conditions, maintaining good oral health and managing systemic diseases are suggested as potential ways to protect against COVID-19.

Periodontitis in individuals with few remaining teeth and a high gingival bleeding index increases the probability of dyslipidemia

BACKGROUND

Dyslipidemia, a silent multifactorial condition, is characterized by changes in blood lipid levels, affecting all socioeconomic strata, increasing the risk for atherosclerotic diseases. This study investigated whether there is an association between dyslipidemia and the combined exposure of periodontitis plus the number of remaining teeth, gingival bleeding, or caries.

METHODS

A two-center cross-sectional study was conducted involving 1270 individuals, with a minimum age of 18 years. Socioeconomic and demographic data, health conditions, lifestyle parameters, and anthropometric, biochemical, and oral clinical examinations were performed. The exposures considered were the presence of periodontitis, dental caries, number of remaining teeth, and gingival bleeding. The outcome was dyslipidemia as defined by the Brazilian Guidelines on Dyslipidemia and Prevention of Atherosclerosis. The combined associations between periodontitis plus other oral health conditions and dyslipidemia were estimated using confounder-adjusted prevalence ratios (PRsingle , PRmultiple , for single and multiple covariable adjustments) with 95% confidence intervals (95% CIs), in a Poisson regression model with robust variance.

RESULTS

The occurrence of dyslipidemia was 70.1% and periodontitis was 84.1%. A positive association between periodontitis and dyslipidemia existed: PRsingle  = 1.13; 95% CI: 1.01-1.26. Combined exposure of periodontitis plus <11 remaining teeth (PRmultiple  = 1.23; 95% CI: 1.05-1.43), as well as combined exposure of periodontitis plus ≥10% gingival bleeding and <11 remaining teeth (PRmultiple  = 1.22; 95% CI: 1.03-1.44), represented greater probabilities of 23% and 22% of individuals having a diagnosis of dyslipidemia.

CONCLUSION

Periodontitis combined with fewer than 11 teeth doubled the likelihood of being diagnosed with dyslipidemia.

Coffee consumption and periodontitis: a Mendelian Randomization study

BACKGROUND

Coffee is one of the most consumed beverages in the world, coffee consumption has been growing in the United States over the past 20 years. Periodontitis is defined by the pathologic loss of the periodontal ligament and destruction of the connective tissue attachment and alveolar bone loss and is related to different systemic diseases and conditions. However, the causality has remained unclarified, thus we regarded discovering the causal relationship between coffee consumption and the liability to periodontitis as the objective of the study.

METHODS

Coffee consumption was subdivided into binary coffee consumption and continuous coffee consumption to refine the study design. Genetic instruments were stretched from the MRC-IEU's (MRC Integrative Epidemiology Unit) output from the GWAS pipeline using phesant-derived variables based on the UK Biobank, the Gene-Lifestyle Interactions in Dental Endpoints (GLIDE) project, and the joint meta-analysis of a recent GWAS. The IVW (Inverse Variance Weighted) was regarded as the primary method to estimate the causality, a scatter plot revealed the intuitive result, and tests for stability were also carried out.

RESULTS

An effect of continuous coffee consumption on the risk of periodontitis was found, with per SD of coffee consumed increases, the risk of periodontitis rises by 1.04% (Odds Ratio of IVW is 1.0104), while the effect of binary coffee consumption on periodontitis did not meet the requirement of indicating a strong causal association, neither were the reverse causality analyses.

CONCLUSIONS

The study indicated the causality of continuous coffee consumption to the risk of periodontitis with a relatively small scale of effect estimate and no strong evidence for an effect of binary coffee-consuming behavior on periodontitis. There was also no intensive evidence suggesting reverse causality.

Sex effects on gingival transcriptomic patterns during initiation, progression, and resolution of periodontitis

BACKGROUND

The prevalence and severity of periodontitis demonstrates altered population distribution with age, sex, and race and ethnicity. While males exhibit greater frequency of disease, particularly with aging, the underlying basis for this observation remains obscure.

OBJECTIVE

This study used a nonhuman primate (Macaca mulatta) model of experimental ligature-induced periodontitis in adult animals to evaluate gingival transcriptomic differences stratified based upon sex of the animal.

METHODS

The 18 animals represented humans ages 40-80 years, with gingival tissue samples obtained at baseline, 0.5 months (initiation), 1 and 3 months (progression), and at 5 months that were 60 days after ligature removal for clinical disease resolution. Microarray analysis was used to quantify gene expression profiles in the gingival tissues.

RESULTS

The results demonstrated clear gene expression differences in healthy (baseline) tissues between the sexes, with elevations in females associated with immune responses and elevation in males related to tissue structural genes. With disease initiation, fewer genes differed between the sexes, while these differences were significantly increased in progressing disease and resolution, particularly in male animals. Overexpressed biological processes showed tissue structural/functional genes at initiation, with host response pathways altered during disease progression. Resolution samples generally demonstrated biological processes of cellular metabolism that differed from baseline healthy samples.

CONCLUSION

The transcriptomic findings support sex as a biological variable in periodontitis using a nonhuman primate model of experimental periodontitis.

Causal relationship between circulating lipid traits and periodontitis: univariable and multivariable Mendelian randomization

Introduction

The correlation between dyslipidemia and periodontitis is revealed through epidemiological studies. However, the results are affected by several confounding factors. This study aims to elucidate the genetic causal association between circulating lipid traits and periodontitis by two-sample Mendelian randomization (MR) analysis.

Methods

After the different screening processes, two cohorts of circulating lipid traits from the UK Biobank were used as exposure data, including five circulating lipid traits. The Periodontitis cohort was selected from the GeneLifestyle Interactions in Dental Endpoints (GLIDE) consortium as outcome data. In univariable MR, the inverse variance weighted (IVW) was used in conjunction with six additional analytical methods to assess causality. The Cochran Q test, IGX 2 statistic, MR-PRESSO, and MR-Egger intercept were used to quantify heterogeneity and pleiotropy. The multivariable MR-IVW (MVMR-IVW) and MVMR-robust were mainly used as analytical methods in the multiple MR analyses.

Results

The IVW estimates showed that genetically predicted Apolipoprotein A1 (apo A1) [odds ratio (OR)=1.158, 95% confidence interval (CI)=1.007-1.331, P-value=0.040] was potentially associated with the risk of periodontitis, but the statistical power of the results was low. Multivariable MR analysis did not reveal any significant causal relationship between apo A1 and periodontitis (OR=0.72, 95% CI=0.36-1.41, P-value=0.34). In the validation cohort, there was also no significant causal relationship between apo A1 and periodontitis (OR=1.079, 95% CI=0.903-1.290, P-value=0.401). Meanwhile, genetically predicted Apolipoprotein B (apo B), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) (all P-values>0.05) were not significantly associated with the risk of periodontitis causal inference.

Conclusion

This MR analysis was unable to provide genetic evidence for the influence of these five circulating lipid traits on periodontitis. However, a more extensive study with a more comprehensive circulating lipid profile and periodontitis data is needed due to study limitations.

CREB5 hypermethylation involved in the ganglioside GM1 therapy of Parkinson's disease

Introduction

The treatment with monosialotetrahexosylganglioside (GM1) improves the symptoms of Parkinson's disease (PD). The alteration of DNA methylation in the blood was examined to investigate epigenetic modification by GM1 treatment.

Methods

After a 28-day continuous intravenous infusion of GM1 (100mg), the motor and non-motor symptoms were evaluated by UPDRS III, Mini-mental state examination (MMSE) scores, FS-14, SCOPA-AUT, and PDQ-8. Moreover, blood samples were collected and PBMC was isolated. Genome-wide DNA methylation was performed by an 850K BeadChip. RNA levels and apoptosis were examined by RT-PCR and flow cytometry in rotenone-based cell models. The CREB5 plasmid was transfected by electroporation into SH-SY5Y cells. We also identified 235 methylation variable positions achieving genome-wide significance in 717558 differentially methylated positions (DMPs) (P = 0.0003) in comparison of pre-treatment with post-treatment measurements (statistical analysis paired-samples t-test).

Results

By searching the Gene Expression Omnibus (GEO) dataset and GWAS, 23 methylation variable positions were screened. Moreover, there are 7 hypomethylated methylation variable positions correlated with the scores of motor symptoms (UPDRS III scale). According to KEGG pathways enrichment analysis, the methylated genes CACNA1B (hypomethylated), CREB5 (hypermethylated), GNB4 (hypomethylated), and PPP2R5A (hypomethylated) were enriched in the dopaminergic synapse pathway. Pretreated with GM1 (80 μM) for 1 h, cell apoptosis and impaired neurite outgrowth were inhibited in rotenone-induced PD cell models. The RNA expression of CREB5 was increased in rotenone-treated SH-SY5Y cells. GM1 treatment decreased rotenone-induced CREB5 gene expression. The enhancement of CREB5 gene expression suppressed the protective role of GM1 in rotenone-induced cell apoptosis.

Discussion

The application of GM1 improves the motor and non-motor symptoms of PD associated with the decreased CREB5 expression and the hypermethylation of CREB5.

Clinical trial registration

https://www.chictr.org.cn/showproj.html?proj=120582t, identifier ChiCTR2100042537.

Effects of metformin on human gingival fibroblasts: an in vitro study

OBJECTIVE

To investigate the effects of metformin (MF) treatment on the matrix metalloproteinases (MMPs) and proinflammatory cytokines production from lipopolysaccharide (LPS) - stimulated human gingival fibroblasts (HGFs).

METHODS

HGFs were obtained from subcultures of biopsies from clinically healthy gingival tissues of patients undergoing oral surgeries. Cell cytotoxicity assay was used to determine the effect of different concentrations of MF on viability of HGFs. HGFs were then incubated and treated with different concentrations of MF and Porphyromonas gingivais (Pg) LPS. MMP-1, MMP-2, MMP-8, MMP-9, IL-1β, and IL-8 expression analysis was performed using xMAP technology (Luminex 200, Luminex, Austin, TX, USA). Student's t-test for a single sample was used to compare the mean values of the study groups with the control value. A p-value of <0.05 and 95% confidence intervals were used to report the statistical significance and precision of mean values.

RESULTS

Concentrations of 0.5, 1- and 2-mM MF had a minimal non-significant cytotoxic effect on the HGFs and caused statistically significant reduction of MMP-1, MMP-2, MMP-8 and IL-8 expressed by the LPS-stimulated HGFs.

CONCLUSION

The results of the present study confirm that MF suppresses MMP-1, MMP-2, MMP-8 and IL-8 in LPS-stimulated HGFs suggesting an anti-inflammatory effect of MF and potential adjunct therapeutic role in the treatment of periodontal diseases.

Salivary leukocyte esterase activity by SillHa is a risk indicator of periodontal disease

BACKGROUND

There is increasing evidence that diagnostic salivary tests measuring inflammatory biomarkers are being developed to assess inflammatory status for early detection, prevention, and progression of periodontal disease. Therefore, the aim of the present study was to investigate and identify the salivary biomarker that can predict the inflammatory status of periodontal disease.

METHODS

A total of 36 patients (28 women and 8 men) with an average age of 57 years were investigated. Unstimulated saliva was collected from the recruited subjects and analyzed using SillHa, a saliva-testing device that measures bacteria count, saliva buffer capacity, acidity, leukocyte esterase, protein, and ammonia. Periodontal parameters were then obtained by clinical examination and initial periodontal therapy was performed. Data obtained with SillHa were compared with clinical periodontal parameters at baseline, re-examination (three months from baseline), and final examination (six months from re-examination).

RESULTS

Leukocyte esterase activity in saliva measured by SillHa; BOP and PCR measured by clinical examination showed a significant difference between baseline and final examination and between re-examination and final examination. Patients in the lower median group (group 1) had a significant difference in leukocyte esterase activity between baseline and final examination and re-examination and final examination. In addition, patients in Group 1 had significantly lower BOP between baseline and final examination. While patients in the higher median group (group 2) showed a modest decrease in leukocyte esterase activity, which was significant only between baseline and final examination, no significant changes were observed concerning BOP. Furthermore, the associated systemic disease was observed in 30% and 81.2% of group 1 and 2 patients, respectively.

CONCLUSION

The results suggest that leukocyte esterase activity in saliva measured by SillHa could serve as a reliable diagnostic marker for monitoring inflammatory status in periodontal disease.

The need for integrated research autopsies in the era of precision oral medicine

BACKGROUND

Autopsy has benefited the practice of medicine for centuries; however, its use to advance the practice of oral health care is relatively limited. In the era of precision oral medicine, the research autopsy is poised to play an important role in understanding oral-systemic health, including infectious disease, autoimmunity, craniofacial genetics, and cancer.

TYPES OF STUDIES REVIEWED

The authors reviewed relevant articles that used medical and dental research autopsies to summarize the advantages of minimally invasive autopsies of dental, oral, and craniofacial tissues and to outline practices for supporting research autopsies of the oral and craniofacial complex.

RESULTS

The authors provide a historical summary of research autopsy in dentistry and provide a perspective on the value of autopsies for high-resolution multiomic studies to benefit precision oral medicine. As the promise of high-resolution multiomics is being realized, there is a need to integrate the oral and craniofacial complex into the practice of autopsy in medicine. Furthermore, the collaboration of autopsy centers with researchers will accelerate the understanding of dental, oral, and craniofacial tissues as part of the whole body.

CONCLUSIONS

Autopsies must integrate oral and craniofacial tissues as part of biobanking procedures. As new technologies allow for high-resolution, multimodal phenotyping of human samples, using optimized sampling procedures will allow for unprecedented understanding of common and rare dental, oral, and craniofacial diseases in the future.

PRACTICAL IMPLICATIONS

The COVID-19 pandemic highlighted the oral cavity as a site for viral infection and transmission potential; this was only discovered via clinical autopsies. The realization of the integrated autopsy's value in full body health initiatives will benefit patients across the globe.

Cellular senescence with SASP in periodontal ligament cells triggers inflammation in aging periodontal tissue

The direct cause of periodontitis is periodontopathic bacteria, while various environmental factors affect the severity of periodontitis. Previous epidemiological studies have shown positive correlations between aging and periodontitis. However, whether and how aging is linked to periodontal health and disease in biological processes is poorly understood. Aging induces pathological alterations in organs, which promotes systemic senescence associated with age-related disease. Recently, it has become evident that senescence at the cellular level, cellular senescence, is a cause of chronic diseases through production of various secretory factors including proinflammatory cytokines, chemokines, and matrix metalloproteinases (MMPs), which is referred to the senescence-associated secretory phenotype (SASP). In this study, we examined the pathological roles of cellular senescence in periodontitis. We found localization of senescent cells in periodontal tissue, particularly the periodontal ligament (PDL), in aged mice. Senescent human PDL (HPDL) cells showed irreversible cell cycle arrest and SASP-like phenotypes in vitro. Additionally, we observed age-dependent upregulation of microRNA (miR)-34a in HPDL cells. These results suggest that chronic periodontitis is mediated by senescent PDL cells that exacerbate inflammation and destruction of periodontal tissues through production of SASP proteins. Thus, miR-34a and senescent PDL cells might be promising therapeutic targets for periodontitis in elderly people.

Salivary irisin level is higher and related with interleukin-6 in generalized periodontitis

OBJECTIVES

Irisin plays an important role in energy homeostasis, inflammation, glucose, and lipid metabolism, and it is shown to have relations with many inflammatory diseases. The aim of the study was to determine saliva and serum irisin and IL-6 levels in patients with stage III/grade B periodontitis compared with individuals with healthy periodontium.

MATERIALS AND METHODS

Twenty patients with stage III grade B periodontitis (P) and 20 periodontally healthy subjects (control; C) were included in this study. Clinical periodontal measurements were recorded. Saliva and serum levels of irisin and interleukin-6 (IL-6) were analyzed by enzyme-linked immunosorbent assay.

RESULTS

Salivary irisin and IL-6 levels were significantly higher in the periodontitis group (p < 0.001, p = 0.002, respectively). Furthermore, serum IL-6 levels were found significantly higher in the periodontitis group compared with controls (p = 0.011). There was no significant difference between the periodontitis and control for serum irisin levels (p > 0.05). Significant positive correlations were found between all periodontal parameters and salivary irisin and IL-6 (p < 0.05) and also between BMI and saliva and serum IL-6 (respectively; r = 0.530, r = 0.329, p < 0.05). There was a positive correlation between salivary irisin and IL-6 (r = 0.369, p < 0.05).

CONCLUSIONS

Monitoring of salivary irisin and IL-6 might be potential biomarker for predicting the susceptibility to periodontitis.

CLINICAL RELEVANCE

Scientific rationale for the study: Irisin is a novel adipomyokine that has played an important role in energy homeostasis, glucose and lipid metabolism, angiogenesis, immunity, and inflammation. Irisin is involved in the pathogenesis of diseases affecting many body systems. IL-6, another adipomyokine, is a major inflammatory mediator and homeostatic regulator of glucose and lipid metabolism and is associated with periodontitis. No studies investigated the relationship between advanced periodontal disease, irisin, and IL-6 together.

PRINCIPAL FINDINGS

The salivary irisin and IL-6 levels were significantly higher and positively correlated in patients with periodontitis relative to healthy controls. Furthermore, serum IL-6 levels were significantly increased in patients with periodontitis.

PRACTICAL IMPLICATIONS

The study shows that irisin and IL-6 can be candidate salivary biomarkers for periodontitis and predict to periodontal status.

Quantifying red complex bacteria, oral hygiene condition, and inflammation status in elderly: A pilot study

Introduction

Periodontitis is an inflammation of the periodontal apparatus leads to destruction of connective tissue attachment and tooth loss. Red complex bacteria may contribute to disease initiation. Bacterial infection in periodontitis leads to a low-grade chronic infection and inflammation in distant organs. Notably, aging can affect the immune response.

Objectives

The aim of this study was to analyze the effect of aging on oral hygiene and inflammation condition. Moreover, to evaluate the correlation between the oral hygiene condition and red complex bacterial load in subgingival plaque.

Materials and methods

In this cross-sectional study, we examined 20 adult and 20 elderly subjects with periodontitis. Clinical parameters included Oral Hygiene Index Simplified (OHI-S) and Papillary Bleeding Index (PBI) were recorded. Subgingival plaque was collected from the tooth with a probing depth of 5-7 mm and analyzed with a reverse transcription polymerase chain reaction (RT-PCR) for red complex bacteria quantification. Statistical analysis was performed, respectively.

Results

Both groups had poor oral hygiene conditions, reflected by high OHI-S and PBI. The quantity of red complex bacteria (P. gingivalis, T. denticola, T. forsythia) in the elderly group was significantly higher in comparison to the adult group. There was significant strong linear relationship between OHI-S and red complex bacteria (r < 1, p < 0.05). Only P. gingivalis bacteria with PBI values had a strong linear relationship and statistically significant. (r < 1, p < 0.05). P. gingivalis load was significantly higher than T. denticola and T. forsythia load, and it correlated with poor oral hygiene in the adult and elderly groups and with PBI in the elderly group.

Conclusions

Aging affects to the red complex bacterial load and oral hygiene condition, but not the inflammation. These findings contribute to the development of novel treatment strategies focusing on bacterial aspect for periodontitis in the elderly.

Reverse causal relationship between periodontitis and shortened telomere length: Bidirectional two-sample Mendelian random analysis

Background

Observational studies have demonstrated a link between shortened telomere lengths(TL) and chronic periodontitis. However, whether the shortened TL is the cause or the result of periodontitis is unknown.Therefore, our objective was to investigate a bidirectional causal relationship between periodontitis and TL using a two-sample Mendel randomized (MR) study.

Methods

A two-sample bidirectional MR analysis using publicly available genome-wide association study (GWAS) data was used. As the primary analysis, inverse variance weighting (IVW) was employed. To identify pleiotropy, we used leave-one-out analysis, MR-Egger, Weighted median, Simple mode, Weighted mode, and MR pleiotropy residual sum and outlier (MR-PRESSO).

Results

In reverse MR results, a genetic prediction of short TL was causally associated with a higher risk of periodontitis (IVW: odds ratio [OR]: 1.0601, 95% confidence interval [CI]: 1.0213 to 1.1002; P =0.0021) and other complementary MR methods. In the forward MR analysis, periodontitis was shown to have no significant effect on TL (IVW: p = 0.7242), with consistent results for the remaining complementary MR. No pleiotropy was detected in sensitivity analysis (all P>0.05).

Conclusion

Our MR studies showed a reverse causal relationship, with shorten TL being linked to a higher risk of periodontitis, rather than periodontitis shorten that TL. Future research is needed to investigate the relationship between cell senescence and the disease.

Identification and validation of a classifier based on hub aging-related genes and aging subtypes correlation with immune microenvironment for periodontitis

BACKGROUND

Periodontitis (PD), an age-related disease, is characterized by inflammatory periodontal tissue loss, and with the general aging of the global population, the burden of PD is becoming a major health concern. Nevertheless, the mechanism underlying this phenomenon remains indistinct. We aimed to develop a classification model for PD and explore the relationship between aging subtypes and the immune microenvironment for PD based on bioinformatics analysis.

MATERIALS AND METHODS

The PD-related datasets were acquired from the Gene Expression Omnibus (GEO) database, and aging-related genes (ARGs) were obtained from the Human Aging Genomic Resources (HAGR). Four machine learning algorithms were applied to screen out the hub ARGs. Then, an artificial neural network (ANN) model was constructed and the accuracy of the model was validated by receiver operating characteristic (ROC) curve analysis. The clinical effect of the model was evaluated by decision curve analysis (DCA). Consensus clustering was employed to determine the aging expression subtypes. A series of bioinformatics analyses were performed to explore the PD immune microenvironment and its subtypes. The hub aging-related modules were defined using weighted correlation network analysis (WGCNA).

RESULTS

Twenty-seven differentially expressed ARGs were dysregulated and a classifier based on four hub ARGs (BLM, FOS, IGFBP3, and PDGFRB) was constructed to diagnose PD with excellent accuracy. Subsequently, the mRNA levels of the hub ARGs were validated by quantitative real-time PCR (qRT-PCR). Based on differentially expressed ARGs, two aging-related subtypes were identified. Distinct biological functions and immune characteristics including infiltrating immunocytes, immunological reaction gene sets, the human leukocyte antigen (HLA) gene, and immune checkpoints were revealed between the subtypes. Additionally, the black module correlated with subtype-1 was manifested as the hub aging-related module and its latent functions were identified.

CONCLUSION

Our findings highlight the critical implications of aging-related genes in modulating the immune microenvironment. Four hub ARGs (BLM, FOS, IGFBP3, and PDGFRB) formed a classification model, and accompanied findings revealed the essential role of aging in the immune microenvironment for PD, providing fresh inspiration for PD etiopathogenesis and potential immunotherapy.

Phytochemical Variability, In Vitro and In Vivo Biological Investigations, and In Silico Antibacterial Mechanisms of Mentha piperita Essential Oils Collected from Two Different Regions in Morocco

The objective of this work is to explore the phytochemical profile of Mentha piperita essential oils (MPEO) collected from two different Moroccan regions using gas chromatography-mass spectrophotometer (GC-MS) and to investigate their antioxidant, anti-inflammatory, antidiabetic and, antimicrobial effects using in vivo and in vitro assays. The chemical constituent of MPEO from the Azrou zone is dominated by carvone (70.25%), while MPEO from the Ouazzane zone is rich in Menthol (43.32%) and Menthone (29.4%). MPEO from Ouezzane showed higher antioxidant activity than EO from Azrou. Nevertheless, EO from Ouezzane considerably inhibited 5-Lipoxygenase (IC50 = 11.64 ± 0.02 µg/mL) compared to EO from Azro (IC50 = 23.84 ± 0.03 µg/mL). Both EOs from Azrou and Ouazzane inhibited the α-amylase activity in vitro, with IC50 values of 131.62 ± 0.01 µg/mL and 91.64 ± 0.03 µg/mL, respectively. The EOs were also tested for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The discdiffusion test revealed that MPEOs from both regions have significant antibacterial efficacy, and MPEOs from the north region showed the highest effect. The gram-positive bacteria were the most susceptible organisms. The MIC concentrations were in the range of 0.05 to 6.25 mg/mL, and the MBC concentrations were within 0.05-25.0 mg/mL. The MBC/MIC index indicated that MPEO has strong bactericidal effects.

Prevalence of Periodontal Disease among Patients at the Outpatient Clinic of Internal Medicine in an Academic Hospital in The Netherlands: A Cross-Sectional Pilot Study

There is a worldwide increase in individuals suffering ≥2 chronic diseases (multimorbidity), and the cause of combinations of conditions remains largely unclear. This pilot study analysed the prevalence of periodontal disease (PD) among (multi)-morbid patients at the outpatient clinic of internal medicine. PD is an inflammatory disease of the tooth supporting tissues and has a negative impact on the overall health. Data were obtained from 345 patients, on demographics, systemic conditions and presence of PD. The possible differences in the distribution of PD status among patients with/without multimorbidity and Medical Subject Headings (MeSH) disease chapters were explored. In total, 180 (52.2%) patients suffered from multimorbidity. The prevalence of severe PD was 16.2%, while the prevalence of mild and severe PD combined (Total PD) was 53.6%. Patients with disease chapter cardiovascular diseases (CVD) had a significantly higher prevalence of severe PD (odds ratio (OR) 2.33; 95% confidence interval (CI) 1.25, 4.33) and Total PD (OR 1.61; 95% CI 1.04, 2.50) than patients without CVD. After subsequent analyses, myocardial infarction was significantly associated with severe PD (OR: 4.68 (95% CI; 1.27 to 17.25)). Those suffering from multimorbidity showed to have a non-significant increased risk for severe (OR 1.27; 95% CI 0.69, 2.34) or Total PD (OR 1.23; 95% CI 0.81, 1.88). In conclusion, PD is highly prevalent in multimorbidity patients. Furthermore, PD was significantly prevalent in patients with CVD. However, larger epidemiological studies are necessary to confirm that the prevalence of PD is significantly increased among multimorbid patients.

Evidence from the Hamburg City Health Study - association between education and periodontitis

OBJECTIVE

Large-scale population-based studies regarding the role of education in periodontitis are lacking. Thus, the aim of the current study was to analyze the potential association between education and periodontitis with state of the art measured clinical phenotypes within a large population-based sample from northern Germany.

MATERIAL & METHODS

The Hamburg City Health Study (HCHS) is a population-based cohort study registered at ClinicalTrial.gov (NCT03934957). Oral health was assessed via plaque-index, probing depth, gingival recession and gingival bleeding. Periodontitis was classified according to Eke & Page. Education level was determined using the International Standard Classification of Education (ISCED-97) further categorized in "low, medium or high" education. Analyses for descriptive models were stratified by periodontitis severity. Ordinal logistic regression models were stepwise constructed to test for hypotheses.

RESULTS

Within the first cohort of 10,000 participants, we identified 1,453 with none/mild, 3,580 with moderate, and 1,176 with severe periodontitis. Ordinal regression analyses adjusted for co-variables (age, sex, smoking, diabetes, hypertension and migration) showed that the education level (low vs. high) was significantly associated with periodontitis (OR: 1.33, 95% CI: 1.18;1.47).

CONCLUSION

In conclusion, the current study revealed a significant association between the education level and periodontitis after adjustments for a set of confounders. Further research is needed to develop strategies to overcome education related deficits in oral and periodontal health.

Periodontitis in Italian patients with established rheumatoid arthritis: A cross-sectional study

OBJECTIVE

To assess the prevalence and severity of periodontitis (P) among Italian patients affected by rheumatoid arthritis (RA).

MATERIALS AND METHODS

A full-mouth periodontal examination and a rheumatologic examination were performed. RA disease activity was scored using the DAS28. Serum analyses investigated levels of rheumatoid factor, anti-citrullinated protein antibodies (ACPAs), C-reactive protein, erythrocyte sedimentation rate and fibrinogen. Information concerning smoking, body mass index and RA medical therapy was collected. Data were analysed by Student's t test, chi-square test, binary logistic regression and Spearman's rank.

RESULTS

This cross-sectional study included 120 subjects, 77 had both diseases while 43 only had RA. The number of teeth present was statistically lower in the RA-P compared to the RA group (p < .05). There were statistically more subjects seropositive for ACPAs in the RA-P group (62.3% vs. 32.6%, p < .05). RA-P patients had an adjusted OR = 2.9 of presenting a moderate-severe DAS28 score (DAS28 ≥ 3.2).

CONCLUSIONS

Higher prevalence of severe P was noted among RA subjects. The clinical severity of RA was strongly correlated with the clinical periodontal parameters, and RA subjects also affected by P had an OR of 2.9 for presenting with a moderate-severe RA (DAS28 score ≥ 3.2).

Host Response Modulation Therapy in the Diabetes Mellitus—Periodontitis Conjuncture: A Narrative Review

The inflammatory response of the host in periodontitis is the phenomenon that underlies the onset and evolution of periodontal destructive phenomena. A number of systemic factors, such as diabetes mellitus (DM), can negatively affect the patient with periodontitis, just as the periodontal disease can aggravate the status of the DM patient. Host response modulation therapy involves the use of anti-inflammatory and anti-oxidant products aimed at resolving inflammation, stopping destructive processes, and promoting periodontal healing, all important aspects in patients with high tissue loss rates, such as diabetic patients. This paper reviews the data available in the literature on the relationship between DM and periodontitis, the main substances modulating the inflammatory response (nonsteroidal anti-inflammatory drugs, sub-antimicrobial doses of doxycycline, or omega-3 fatty acids and their products, specialized pro-resolving mediators), as well as their application in diabetic patients.

Matrix metalloproteinase-9-1562 C/T promoter gene polymorphism in chronic periodontitis: A cross-sectional observational study

Background:

Matrix metalloproteinases (MMPs) are a major group of enzymes, released in inflamed periodontal tissues in large quantities, resulting in connective tissue matrix breakdown. One of the most predominant MMPs is MMP-9. Association between chronic periodontitis (CP) and MMP-9 gene polymorphism (GP) in some ethnic populations has been already established. The aim of the current study was to assess the association of single-nucleotide polymorphism in the promoter region of MMP-9 gene with CP in Kolkata population, if any.

Materials and Methods:

Forty eligible individuals were recruited for the study and grouped as A and B: Group A (twenty periodontally healthy individuals) and Group B (twenty CP patients). Venous blood samples collected from all the forty individuals were used to isolate the genomic DNA. GP for MMP-9 gene was detected using polymerase chain reaction and sequencing method. The data obtained were then analyzed statistically.

Results:

A significantly different genotypic and allelic variation was observed in the control and test groups, with C/T genotype and T allele present in only CP group.

Conclusion:

Within the limitations of this study, we can conclude that there was no significant association between patients with periodontitis and MMP-9-1562 C/T promoter GP.

Can motivational interviewing for dental settings be taught online? Results of an uncontrolled interventional trial

BACKGROUND

Motivational interviewing (MI) is an evidence-based method of promoting oral healthcare behaviour. Conventional training of MI is a time-consuming and costly aspect in the dental curriculum. Therefore, the aim of this study was to evaluate the effectiveness and acceptance of a MI-blended learning programme for dental students.

MATERIALS AND METHODS

Dental students had to perform an interdisciplinary created "ecourse Motivational Interviewing in medical settings" (eMI-med). After completion, patient-student interviews were recorded and evaluated using the Motivational Interviewing Treatment Integrity Code (MITI-d). Furthermore, the students' self-efficacy regarding smoking cessation and oral hygiene motivation was examined and the acceptance of the tool was enquired.

RESULTS

Forty interviews with 25 different students were analysed with the MITI-d. Students showed high levels of MI-adherent behaviour (15.45 ± 6.98), open-ended questions (9.95 ± 6.90) and reflections (10.43 ± 8.85), which were comparable to previous classroom trainings. In addition, 90% of the students preferred e-learning over classroom teaching. Furthermore, the students' therapeutical self-efficacies were significantly increased by the programme.

CONCLUSION

Within the limitations of this study, the created e-learning programme was able to equip dental students with basic knowledge and MI skills. Furthermore, learning MI through e-learning may heighten the self-efficacy of dental students regarding smoking cessation and oral hygiene promotion. Students showed a high acceptance of e-learning, preferring it over traditional learning.

mTOR Signaling in the Regulation of CD4+ T Cell Subsets in Periodontal Diseases

Periodontal disease results from the inflammatory infiltration by the microbial community which is marked through tooth mobility and alveolar bone resorption. The inflammation in periodontal disease is mediated by CD4⁺ T cells through cytokine secretion and osteoclastogenetic activity. Historically, the inflammatory model in periodontal disease is described through disruption of the balance between two subsets of T helper cells which are T-helper type 1 (Th1) and T-helper type 2 (Th2). However, more and more studies have found that apart from subsets of helper T cells, regulatory T-cells and Th17 cells are also involved in the pathogenesis of periodontal diseases. Growing evidence proves that helper T cells differentiation, activation, and subset determination are under the strong impact of mTOR signaling. mTOR signaling could promote Th1 and Th17 cell differentiation and inhibit Treg commitment through different mTOR complexes, therefore we anticipate a regulation effect of mTOR signaling on periodontal diseases by regulating CD4⁺ T cell subsets. This review aims to integrate the topical researches about the role of different types of Th cells in the pathogenesis of periodontal diseases, as well as the regulation of mTOR signaling in the specification and selection of Th cell commitment.

Adherence to mediterranean diet, physical activity level and severity of periodontitis. Results from a University-based cross-sectional study

AIM

to evaluate the association between adherence to Mediterranean Diet (MD) and Physical Activity (PA) level with the periodontal status of a University-based cohort of individuals.

MATERIALS AND METHODS

235 individuals were included in the study. MD adherence and PA level were registered through validated questionnaires, together with a full periodontal examination. Crude and adjusted Odds ratios (ORs) [95% Confidence Interval] were calculated to evaluate the association between MD adherence, PA level and periodontitis severity. A final logistic multivariate regression model was built to evaluate the impact of the combination between low MD adherence and low PA level on the prevalence of stage III/IV periodontitis.

RESULTS

The adjusted ORs for stage III/IV periodontitis were 1.65[0.84-3.28;p = .42] for low PA and 5.63[3.21-9.84;p = .00] for low MD adherence. The final logistic multivariate regression model resulted in OR = 10.23[4.01,26.09;p = .00] of having stage III/IV periodontitis in individuals with low MD adherence and low PA.

CONCLUSIONS

Individuals conducing a lifestyle characterized by the combination of low MD adherence and lack of regular exercise had 10 times the odds to have severe forms of periodontitis. This article is protected by copyright. All rights reserved.

Systemic Periodontal Risk Score Using an Innovative Machine Learning Strategy: An Observational Study

Early diagnosis is crucial for individuals who are susceptible to tooth-supporting tissue diseases (e.g., periodontitis) that may lead to tooth loss, so as to prevent systemic implications and maintain quality of life. The aim of this study was to propose a personalized explainable machine learning algorithm, solely based on non-invasive predictors that can easily be collected in a clinic, to identify subjects at risk of developing periodontal diseases. To this end, the individual data and periodontal health of 532 subjects was assessed. A machine learning pipeline combining a feature selection step, multilayer perceptron, and SHapley Additive exPlanations (SHAP) explainability, was used to build the algorithm. The prediction scores for healthy periodontium and periodontitis gave final F1-scores of 0.74 and 0.68, respectively, while gingival inflammation was harder to predict (F1-score of 0.32). Age, body mass index, smoking habits, systemic pathologies, diet, alcohol, educational level, and hormonal status were found to be the most contributive variables for periodontal health prediction. The algorithm clearly shows different risk profiles before and after 35 years of age and suggests transition ages in the predisposition to developing gingival inflammation or periodontitis. This innovative approach to systemic periodontal disease risk profiles, combining both ML and up-to-date explainability algorithms, paves the way for new periodontal health prediction strategies.

Masulili SL, Kusdhany LS, Prahasanti C, Soedarsono N. Obesity correlated to a higher risk of acquiring periodontitis: a cross-sectional study

Background: The present study aimed to investigate the correlation between obesity and periodontitis, among other risk factors for periodontitis.  

Methods:  In total, 262 Indonesian male and female subjects were analysed for body mass index (BMI), oral hygiene, plaque index, and clinically evaluated periodontitis. Statistical analysis was performed using Spearman tests and Pearson chi-square tests to estimate the correlation between BMI and periodontitis. Multivariate binary logistic analysis was conducted between covariate and periodontitis. P<0.05 was considered as statistically significant.  

Results: The prevalence of obesity was 48.47%. There were positive correlations between BMI and periodontal status for healthy-mild periodontitis, moderate, and severe periodontitis respectively. BMI and periodontitis crude odds ratio (OR) = 2.31 (95% CI 1.41-3.78); p < 0.05, adjusted OR of BMI among other variables, was 1.88 (95%CI 1.05-3.37); p < 0.05. Exploration of the ROC curve found a BMI cut off point of 24.785 kg/m2. 

Conclusion: Obesity by BMI measurement of ≥ 25kg/m2 correlated to a higher risk of acquiring periodontitis compared to normal-weight individuals.

Periodontitis in Ischemic Stroke Patients: Case Definition Challenges of the New Classification Scheme (2018)

The identification of the associative relationships between ischemic stroke (IS) and risk factors such as advanced age and periodontitis is essential to design real screening protocols and to address them using primary and secondary preventive policies. This study primarily aimed to evaluate the diagnostic performance of the 2018 European Federation of Periodontology/American Academy of Periodontology (EFP/AAP) case definition in detecting periodontitis against the 2012 Centers for Disease Control and Prevention/American Academy of Periodontology (CDC/AAP) case definition in a group of IS patients. Secondarily, we report the periodontal status of IS patients and the associative relationship with respect to some risk factors. Patients with their first IS were assessed based on demographic data, medical, oral risk factors and periodontal parameters. The two case definitions were applied to identify the periodontitis burden. The agreement between the two case definition systems, as well as the misclassification ratio, were calculated. A total of 141 patients were included. According to the 2012 CDC/AAP and the 2018 EFP/AAP case definitions, a frequency of periodontitis of 98.5% and 97.8% based on two modalities of inclusion of cases in the severity groups, sensitivity values of 98.54% or 100%, and specificity values of 25% or 14.7% were calculated. Thus, the new case definition system has a higher capacity to detect periodontitis, especially the well-established forms.

Metformin and risk of gingival/periodontal diseases in diabetes patients: A retrospective cohort study

AIM

To compare the risk of gingival and periodontal diseases (GPD) between ever users and never users of metformin in patients with type 2 diabetes mellitus.

METHODS

The Taiwan's National Health Insurance database was used to enroll 423,949 patients with new onset diabetes mellitus from 1999 to 2005. After excluding ineligible patients, 60,309 ever users and 5578 never users were followed up for the incidence of GPD from January 1, 2006 until December 31, 2011. Propensity score-weighted hazard ratios were estimated by Cox regression.

RESULTS

GPD was newly diagnosed in 18,528 ever users (incidence: 7746.51 per 100,000 person-years) and 2283 never users (incidence: 12158.59 per 100,000 person-years). The hazard ratio that compared ever users to never users was 0.627 (95% confidence interval: 0.600-0.655). When metformin use was categorized by tertiles of cumulative duration and cumulative dose, the risk significantly reduced in a dose-response pattern when the cumulative duration reached approximately 2 years or the cumulative dose reached 670 grams. Analyses on the tertiles of defined daily dose of metformin showed that the reduction of GPD risk could be seen in all three subgroups but the benefit would be greater when the daily dose increased.

CONCLUSION

Long-term use of metformin is associated with a significantly reduced risk of GPD.

CHANGES IN IMMUNOLOGICAL INDICATORS UNDER THE INFLUENCE OF TREATMENT OF GENERALIZED PERIODONTITIS IN PATIENTS WITH MANIFESTATIONS OF PSYCHOEMOTIONAL STRESS

OBJECTIVE

The aim: The aim of investigation was to determine the effect of the proposed treatment of patients with generalized periodontitis and psychoemotional stress on changes in the immune system of patients.

PATIENTS AND METHODS

Materials and methods: The clinical and laboratory investigations were conducted to revealed the effectiveness of the proposal complex of adrenoblockers in complex treatment of generalized periodontitis in 40 patients with psychoemotional stress. To assess the effectiveness of the treatment, the level of cortisol in saliva was determined. 40 patients with chronic course of generalized periodontitis I-II grade were divided into two subgroups: main and control. For the treatment of main subgroup patients used a modified enhanced complex of adrenoblockers to suppress the manifestations of psychoemotional stress.

RESULTS

Results: The effectiveness of usage of the proposed complex of adrenoblockers were revealed after treatment of main group patients. The complex of adrenoblockers lead to stabilization of the generalized periodontitis in patients with psychoemotional stress. Such combination of adrenoblockers oppresses main symptoms of psychoemotional stress in with generalized periodontitis as evidenced by the decrease of cortisol levels in the patients saliva.

CONCLUSION

Conclusions: As a result of researches the obtained data testify to achievement of stabilization of pathological process in a periodontium. All this together demonstrates the beneficial effect of the proposed complex of adrenoblockers on the dystrophic-inflammatory process in the periodontium. Decreased levels of cortisol in saliva indicate a decrease in the manifestations of psychoemotional stress in patients with generalized periodontitis.

Oral Colonization by Entamoeba gingivalis and Trichomonas tenax: A PCR-Based Study in Health, Gingivitis, and Periodontitis

Background

The etiology of periodontitis remains unclear, as is the place of gingivitis in its pathophysiology. A few studies linked the colonization by oral parasites (Entamoeba gingivalis and Trichomonas tenax) to periodontal disease and its severity. The aim of the current study was to estimate the prevalence of these oral parasites among healthy individuals, and in patients with gingivitis and periodontitis in Jordan.

Methods

The study was conducted during July 2019–December 2019. Samples were composed of saliva and periodontal material including dental plaque sampled with probes. The detection of oral parasites was done using conventional polymerase chain reaction (PCR).

Results

The total number of study participants was 237: healthy (n=94), gingivitis (n=53) and periodontitis (n=90). The prevalence of E. gingivalis was 88.9% among the periodontitis patients, 84.9% among the gingivitis patients and 47.9% in the healthy group. For T. tenax, the prevalence was 25.6% among the periodontitis patients, 5.7% among the gingivitis patients and 3.2% in the heathy group. Positivity for E. gingivalis was significantly correlated with the presence of periodontal disease compared to the healthy group with odds ratio (OR) of 6.6. Periodontal disease was also correlated with lower monthly income (OR=8.2), lack of dental care (OR=4.8), and history of diabetes mellitus (OR=4.5). Colonization by E. gingivalis was correlated with gingivitis (OR=6.1) compared to the healthy group. Colonization by E. gingivalis and T. tenax were significantly correlated with periodontitis (OR=6.4 for E. gingivalis, and OR=4.7, for T. tenax) compared to the healthy group. T. tenax was only detected among individuals with generalized periodontal disease compared to its total absence among those with localized disease (19.6% vs. 0.0%; p=0.039). The co-infection rate by the two oral parasites was 11.0%.

Conclusions

The higher prevalence of human oral parasites in periodontal disease compared to healthy individuals appears to be more than a mere marker for the disease and might also be associated with disease severity and potential for progression. Thus, the dogmatic view of E. gingivalis and T. tenax as commensals needs to be re-evaluated and their contribution to pathophysiology of periodontal diseases cannot be neglected.

Gut-Bone Axis: A Non-Negligible Contributor to Periodontitis

Periodontitis is a polymicrobial infectious disease characterized by alveolar bone loss. Systemic diseases or local infections, such as diabetes, postmenopausal osteoporosis, obesity, and inflammatory bowel disease, promote the development and progression of periodontitis. Accumulating evidences have revealed the pivotal effects of gut microbiota on bone health via gut-alveolar-bone axis. Gut pathogens or metabolites may translocate to distant alveolar bone via circulation and regulate bone homeostasis. In addition, gut pathogens can induce aberrant gut immune responses and subsequent homing of immunocytes to distant organs, contributing to pathological bone loss. Gut microbial translocation also enhances systemic inflammation and induces trained myelopoiesis in the bone marrow, which potentially aggravates periodontitis. Furthermore, gut microbiota possibly affects bone health via regulating the production of hormone or hormone-like substances. In this review, we discussed the links between gut microbiota and periodontitis, with a particular focus on the underlying mechanisms of gut-bone axis by which systemic diseases or local infections contribute to the pathogenesis of periodontitis.

Evaluation of stress, serum and salivary ghrelin and cortisol levels in smokers and non-smokers with stage iii periodontitis - A cross-sectional study

BACKGROUND

The present study aimed to investigate the serum and salivary ghrelin and cortisol levels in smokers and non-smokers with Stage III Periodontitis.

METHODS

The present study comprised of a total of 90 systemically healthy patients categorized in three groups: Group I- Periodontally healthy patients; Group II- Non-smokers with Stage III Periodontitis and Group III- Smokers with Stage III periodontitis. Clinical parameters of Probing pocket depth (PPD), Clinical attachment levels (CAL), Plaque Index (PI), Gingival Index (GI) and Papillary Bleeding Index (PBI)were recorded and biochemical parameters of serum and salivary ghrelin and cortisol levels were analyzed via Enzyme Linked Immunosorbent Assay (ELISA). Stress levels were assessed using Zung's self-rating depression scale.

RESULTS

Serum and salivary ghrelin values were found to be higher in Group II (620.25 ± 260.86 pg/ml, 892.40 ± 271.65 pg/ml respectively) as compared to Group III. Similarly, salivary as well as serum cortisol levels were higher in Group III (20.78 ± 9.23 pg/ml, 399.37 ±189.21 pg/ml respectively) as compared to Group II (16.36 ± 8.88 pg/ml, 320.68 ± 107.01 pg/ml respectively). In Group III, a direct correlation was observed between stress, serum and salivary cortisol levels while an inverse correlation was found between stress, serum and salivary ghrelin levels. Group III showed a greater number of depressed patients followed by Group II and I.

CONCLUSION

As per the results smokers with Stage III Periodontitis exhibit an elevated stress and cortisol levels, lower serum and salivary ghrelin levels as compared to the non-smokers. This article is protected by copyright. All rights reserved.

Evaluation of the protective effects of non-thermal atmospheric plasma on alveolar bone loss in experimental periodontitis

OBJECTIVES

The inhibition of bone destruction is one of the main goals of periodontitis treatment. The aim of this study was to investigate the protective effects of non-thermal atmospheric plasma (NTAP) on alveolar bone loss radiographically, histomorphometrically, and histologically in experimental periodontitis in rats.

MATERIALS AND METHODS

A total of twenty-eight rats were randomly divided into three groups: control group (CG) (n = 8), periodontitis group (PG) (n = 10), and NTAP group (NTAPG) (n = 10). In PG and NTAPG, experimental periodontitis was created with ligating. The kINPen 11 plasma jet was applied around the ligatured teeth in NTAPG. The samples from each group were radiographically assessed with microcomputed tomography (micro-CT); then, histological (presence of osteoclasts and inflammatory cells) and immunohistochemical (immunoreactive of OCN and ALP) findings were compared.

RESULTS

The results revealed a significant increase in alveolar bone loss in the PG compared with CG and NTAPG (p < 0.05). Inflammation, alveolar resorption, and cement damage were reduced significantly in the group treated with NTAP compared to the PG (p < 0.05). Significantly higher levels of osteoclasts were detected in the PG in comparison with both CG and NTAPG (p < 0.05). The lowest osteocalcin and ALP values were determined in PG, and the differences between PG and both groups were also significant (p < 0.05).

CONCLUSION

Within the limitations of the present study, we can say that NTAP may enhance the bone remodeling process by inhibiting inflammation and preventing alveolar bone destruction.

CLINICAL RELEVANCE

NTAP has clinical potential for accelerating and treating periodontitis with the inflammatory response modulation, osteoblast differentiation, and alveolar bone loss reduction.

Effect of obesity on risk and severity of periodontitis: a cross-sectional study

Background: The present study aimed to investigate the correlation between obesity and periodontitis, among other risk factors for periodontitis.   Methods:  In total, 262 Indonesian male and female subjects were analysed for body mass index (BMI), oral hygiene, plaque index, and clinically evaluated periodontitis. Statistical analysis was performed using Spearman tests and Pearson chi-square tests to estimate the correlation between BMI and periodontitis. Multivariate binary logistic analysis was conducted between covariate and periodontitis. P<0.05 was considered as statistically significant.   Results: The prevalence of obesity was 48.47%. There were positive correlations between BMI and periodontal status for healthy-mild periodontitis, moderate, and severe periodontitis respectively. BMI and periodontitis crude odds ratio (OR) = 2.31 (95% CI 1.41-3.78); p < 0.05, adjusted OR of BMI among other variables, was 1.88 (95%CI 1.05-3.37); p < 0.05. Exploration of the ROC curve found a BMI cut off point of 24.785 kg/m2.  Conclusion: Obesity by BMI measurement of ≥ 25kg/m2 correlated to a higher risk of acquiring periodontitis compared to normal-weight individuals.

Low bone mineral density is associated with severe periodontitis at the end of the second decade of life: A population-based study

AIM

To evaluate the association between low bone mineral density (BMD) and severe periodontitis at the end of the second decade of life.

MATERIALS AND METHODS

This population-based study analysed 2032 youngers (18-19 years old) of the RPS cohort. BMD of lumbar spine (BMD-LS) and of the whole body (BMD-WB) were assessed by dual x-ray emission densitometry. Low BMD-LS (Z-score ≤ -2) and low BMD-WB (Z-score ≤ -1.5) were correlated with severe periodontitis. The extent of periodontal disease was also evaluated as the following outcomes: proportions of teeth affected by clinical attachment loss ≥5 mm and probing depth ≥5 mm. Multivariate models by sex, education, family income, risk of alcohol dependence, smoking, plaque, bleeding index, and body mass index were estimated through logistic regression (binary outcomes) and Poisson regression (continuous outcomes).

RESULTS

The prevalence of severe periodontitis was 10.97%. Low BMD-LS (odds ratio [OR] = 2.08, confidence interval [CI] = 1.12-3.85, p = .01) and low BMD-WB (OR = 1.34, CI = 1.001-1.81, p = .04) were associated with severe periodontitis in the final multivariate models. Low BMD-LS and BMD-WB were also associated with a greater extent of periodontitis (p < .05).

CONCLUSIONS

Low BMD was found to be associated with the severity and extent of periodontitis in adolescents. Adolescents at peak bone mass age presenting low BMD are more likely to be affected by severe periodontitis.

Influence of Materials Properties on Bio-Physical Features and Effectiveness of 3D-Scaffolds for Periodontal Regeneration

Periodontal diseases are multifactorial disorders, mainly due to severe infections and inflammation which affect the tissues (i.e., gum and dental bone) that support and surround the teeth. These pathologies are characterized by bleeding gums, pain, bad breath and, in more severe forms, can lead to the detachment of gum from teeth, causing their loss. To date it is estimated that severe periodontal diseases affect around 10% of the population worldwide thus making necessary the development of effective treatments able to both reduce the infections and inflammation in injured sites and improve the regeneration of damaged tissues. In this scenario, the use of 3D scaffolds can play a pivotal role by providing an effective platform for drugs, nanosystems, growth factors, stem cells, etc., improving the effectiveness of therapies and reducing their systemic side effects. The aim of this review is to describe the recent progress in periodontal regeneration, highlighting the influence of materials' properties used to realize three-dimensional (3D)-scaffolds, their bio-physical characteristics and their ability to provide a biocompatible platform able to embed nanosystems.

Polymicrobial communities in periodontal disease: Their quasi-organismal nature and dialogue with the host

In health, indigenous polymicrobial communities at mucosal surfaces maintain an ecological balance via both inter-microbial and host-microbial interactions that promote their own and the host's fitness, while preventing invasion by exogenous pathogens. However, genetic and acquired destabilizing factors (including immune deficiencies, immunoregulatory defects, smoking, diet, obesity, diabetes and other systemic diseases, and aging) may disrupt this homeostatic balance, leading to selective outgrowth of species with the potential for destructive inflammation. This process, known as dysbiosis, underlies the development of periodontitis in susceptible hosts. The pathogenic process is not linear but involves a positive-feedback loop between dysbiosis and the host inflammatory response. The dysbiotic community is essentially a quasi-organismal entity, where constituent organisms communicate via sophisticated physical and chemical signals and display functional specialization (eg, accessory pathogens, keystone pathogens, pathobionts), which enables polymicrobial synergy and dictates the community's pathogenic potential or nososymbiocity. In this review, we discuss early and recent studies in support of the polymicrobial synergy and dysbiosis model of periodontal disease pathogenesis. According to this concept, disease is not caused by individual "causative pathogens" but rather by reciprocally reinforced interactions between physically and metabolically integrated polymicrobial communities and a dysregulated host inflammatory response.