Bidirectional association between periodontal disease and diabetes mellitus: a systematic review and meta-analysis of cohort studies

Relationship Between Diabetes Mellitus and Periodontal/Peri-Implant Disease: A Contemporaneous Review

The prevalence of diabetes mellitus (DM), a major chronic disease and a leading cause of death and disability around the world, is rising. According to the latest data, the global prevalence of DM has increased to 463 million (9.3% of adults) in 2019 and is estimated to reach 700 million by 2045. Periodontal disease, result of periodontium inflammation, is a common, chronic disease and has long been considered one of the complications of DM. Moreover, literature reflects a spectrum of conflicting viewpoints on the effect of diabetic conditions on the implant treatment strategies. The current review aims to update the recent epidemiologic evidence regarding the relationship between DM and periodontal/peri-implant disease, emphasising the effects of glycaemic control on the severity of these diseases and describing the pathobiological mechanisms underlying this association. This review's findings indicate a bidirectional relationship between DM and periodontal/peri-implant disease and that this relationship seems causal, implying that controlling these two diseases might help prevent each other's incidence. Additionally, the severity of periodontal/peri-implant disease is directly related to metabolic control. Although patients with diabetes can obtain implant success similar to those in systemically healthy individuals, an increased risk of peri-implantitis has been reported in DM patients. Therefore, the importance of glycaemic control and maintaining proper oral hygiene cannot be overstated.

Point-of-care diabetes testing in the dental setting: A national scope of practice survey

OBJECTIVES

The aim of this study was to assess the knowledge of state dental directors regarding their state's professional practice act, specifically scope of practice laws regarding point-of-care chairside screening for diabetes.

METHODS

A cross-sectional study design was used to examine the 50 state dental directors' knowledge of policy around point-of-care diabetes testing in their state. A five-item survey instrument was designed in a web-based platform and electronically distributed in 2022.

RESULTS

Thirty-seven states (74%) responded to the survey. Regarding whether it was within the scope of practice for dentists to provide chairside point-of-care HbA1c screening, 17 states (46.0%) responded "yes," 5 states (13.5%) responded "no," and 15 states (40.5%) responded "don't know." Of the 17 states who provide diabetes testing, four states (23.5%) reported that dentists were reimbursed, nine states (53.0%) reported they were not reimbursed, and four states (23.5%) reported they did not know regarding reimbursement.

CONCLUSIONS

There is significant state heterogeneity with regard to laws, regulations, and reimbursement for chairside diabetes testing in the United States. This is accompanied by vagueness and lack of specificity in the state education laws. For more widespread promotion and adoption of this evidence-based screening, the entire dental community including clinicians, educators, policymakers, payers, and professional organizations at all levels are encouraged to work together to advocate for clarification and specificity in the language of state education laws as well as reimbursement for this vital service.

Associations between periodontitis and serum anti-malondialdehyde-acetaldehyde antibody concentrations in rheumatoid arthritis: A case-control study

BACKGROUND

Malondialdehyde-acetaldehyde (MAA) adducts lead to generation of anti-MAA autoantibodies and have been independently identified in inflamed periodontal and rheumatoid arthritis (RA) tissues. This study evaluates serum samples from RA cases and osteoarthritis (OA) controls to quantify associations between periodontal clinical measures, alveolar bone loss (ABL), and anti-Porphyromonas gingivalis, anti-Prevotella intermedia, and anti-Fusobacterium nucleatum antibody concentrations with anti-MAA antibody concentrations.

METHODS

Participants (n = 284 RA cases, n = 330 OA controls) underwent periodontal clinical assessments and ABL measurements. Serum immunoglobulin (Ig) A, IgG, and IgM anti-MAA and serum IgG antibacterial antibody concentrations were quantified by enzyme-linked immunosorbent assay (ELISA). Analyses utilized simple linear regression and multivariable adjusted models.

RESULTS

No significant associations of periodontal clinical measures with serum anti-MAA were found. Moderate (p = 0.038 and p = 0.036, respectively) and high ABL (p = 0.012 and p = 0.014, respectively) in RA cases (but not in OA) were positively associated with IgG and IgM anti-MAA. Anti-P. gingivalis and anti-P. intermedia antibody concentrations were positively associated with IgA (p = 0.001 for both), IgG (p = 0.007 and p = 0.034, respectively), and IgM anti-MAA antibody concentrations (p < 0.001 and p = 0.020, respectively), while anti-F. nucleatum was positively associated with IgG anti-MAA (p = 0.042), findings that were similar across groups.

CONCLUSIONS

A positive association was demonstrated between ABL and serum IgG and IgM anti-MAA antibody concentrations that was unique to RA and not observed in OA. Serum anti-P. gingivalis, anti-P. intermedia, and anti-F. nucleatum antibody concentrations displayed significant associations with anti-MAA antibody in both groups. These findings suggest MAA may play a role in the interrelationship between the periodontium and RA.

The impact of systemic administration of polyphenols on periodontitis associated with diabetes mellitus: a systematic review

OBJECTIVE

The aim of this work was to explore the potential of polyphenol supplement consumption in enhancing the treatment of periodontitis and diabetes mellitus in both diabetic animals and humans.

MATERIALS AND METHODS

A comprehensive search across eight databases (MEDLINE, EBSCO, Taylor & Francis, PRIMO, Web of Science, Wiley Online Library, ScienceDirect, and SAGE Journals) and two registers (ClinicalTrials.gov and Cochrane Library Trials) was conducted. Methodological quality assessment employed the Cochrane Collaboration Risk of Bias Assessment Tool for randomised controlled trials and the Systematic Review Centre for Laboratory Animal Experimentation Risk of Bias Tool for experimental animal studies.

RESULTS

Ten articles meeting inclusion criteria were identified. Three clinical studies demonstrated significant reductions in probing depth (PD) and clinical attachment loss (CAL). Ginger supplementation showed a decrease in CAL (-0.57 ± 0.50 vs. -0.14 ± 0.35, p = 0.003) and PD (-0.52 ± 0.51 vs. -0.19 ± 0.51, p = 0.04), while resveratrol supplementation exhibited a reduction in PD (-1.1 ± 0.58 vs. -0.6 ± 0.47, p < 0.001). Additionally, cranberry juice supplementation led to a decrease in PD (-0.56 ± 0.03, p < 0.001). However, there was no significant improvement in inflammation status. Although polyphenol supplementation did not impact fasting blood glucose levels, it did result in improved insulin resistance (3.66 ± 0.97 vs. 4.49 ± 1.56, p = 0.045). In diabetic animals, six studies reported a significant reduction (p < 0.05) in bone loss along with marked improvements in inflammation status.

CONCLUSIONS

Despite the promising results observed in the included studies, the overall evidence supporting the positive effects of polyphenols on periodontal and diabetes mellitus status, along with their anti-inflammatory properties, remains inadequate.

Clinical attachment loss is cross-sectionally associated with elevated glucose among adults without diabetes

AIM

We investigated whether periodontal measures are cross-sectionally associated with prediabetes and cardiometabolic biomarkers among non-diabetic younger adults.

MATERIALS AND METHODS

One thousand seventy-one participants (mean age = 32.2 years [SE = 0.3]; 73% female) from the Oral Infections, Glucose Intolerance and Insulin Resistance Study were enrolled. Full-mouth clinical attachment loss (fm-CAL), probing depth (fm-PD) and bleeding on probing were ascertained. Interproximal CAL (i-CAL) and probing depths (i-PD) served as our primary exposures. Glucose, HbA1c, insulin and insulin resistance (HOMA-IR) outcomes were assessed from fasting blood. Prediabetes was defined per American Diabetes Association guidelines. Prediabetes prevalence ratios (PR [95% CI]) and mean [SE] cardiometabolic biomarkers were regressed on periodontal variables via multivariable robust variance Poisson regression or multivariable linear regression.

RESULTS

Prevalence of prediabetes was 12.5%. Fully adjusted prediabetes PR in Tertiles 3 versus 1 of mean i-CAL was 2.42 (1.77, 3.08). Fully adjusted fasting glucose estimates across i-CAL tertiles were 83.29 [0.43], 84.31 [0.37], 86.48 [0.46]; p for trend <.01. Greater percent of sites with i-PD ≥3 mm showed elevated natural-log-HOMA-IR after adjustment (0%-12% of sites = 0.33 [0.03], 13%-26% of sites = 0.39 [0.03], ≥27% of sites = 0.42 [0.03]; p for trend = .04).

CONCLUSIONS

i-CAL (vs. fm-CAL) was associated with elevated fasting glucose and prediabetes, whereas i-PD (vs. fm-PD) was associated with insulin resistance. Future studies are needed to examine periodontal disease and incident prediabetes.

Identifying MS4A6A+ macrophages as potential contributors to the pathogenesis of nonalcoholic fatty liver disease, periodontitis, and type 2 diabetes mellitus

Purpose

Concrete epidemiological evidence has suggested the mutually-contributing effect respectively between nonalcoholic fatty liver disease (NAFLD), type 2 diabetes mellitus (T2DM), and periodontitis (PD); however, their shared crosstalk mechanism remains an open issue.

Method

The NAFLD, PD, and T2DM-related datasets were obtained from the NCBI GEO repository. Their common differentially expressed genes (DEGs) were identified and the functional enrichment analysis performed by the DAVID platform determined relevant biological processes and pathways. Then, the STRING database established a PPI network of such DEGs and topological analysis through Cytoscape 3.7.1 software along with the machine-learning analysis by the least absolute shrinkage and selection operator (LASSO) algorithm screened out hub characteristic genes. Their efficacy was validated by external datasets using the receiver operating characteristic (ROC) curve, and gene expression and location of the most robust one was determined using single-cell sequencing and immunohistochemical staining. Finally, the promising drugs were predicted through the CTD database, and the CB-DOCK 2 and Pymol platform mimicked molecular docking.

Result

Intersection of differentially expressed genes from three datasets identified 25 shared DEGs of the three diseases, which were enriched in MHC II-mediated antigen presenting process. PPI network and LASSO machine-learning analysis determined 4 feature genes, of which the MS4A6A gene mainly expressed by macrophages was the hub gene and key immune cell type. Molecular docking simulation chosen fenretinide as the most promising medicant for MS4A6A+ macrophages.

Conclusion

MS4A6A+ macrophages were suggested to be important immune-related mediators in the progression of NAFLD, PD, and T2DM pathologies.

Association between life's essential 8 and periodontitis: a study based on NHANES 2009-2014

Background

This research aims to investigate the relationship between Life's Essentials 8 (LE8), the American Heart Association's latest indicator, and periodontitis. The purpose is to provide guidance on preventative measures.

Methods

Data for our investigation were obtained from the National Health and Nutrition Examination Survey (NHANES) 2009-2014, with a total of 8,784 participants eligible. LE8 scores were compiled from 8 index scores (the score for each component of diet, physical activity, nicotine exposure, sleep duration, body mass index, blood lipids, blood glucose, and blood pressure). Periodontitis was classified by the Centers for Disease Control and Prevention and American Academy of Periodontology (CDC/AAP). The study utilized multivariable logistic analyses to investigate the potential correlation.

Results

After controlling for all covariates, LE8 was discovered to have a significant negative correlation with periodontitis prevalence [0.91 (0.88, 0.94)]. This trend continued to hold statistical significance even after converting LE8 into a categorical variable. Furthermore, a noteworthy adverse correlation was discovered across both genders, specifically males [0.35 (0.22, 0.55)] and females [0.39 (0.25, 0.60)], as well as for the majority of categorical classifications, namely ethnicity, age, education level, and marital status. However, only the age subgroups displayed some degree of significant difference from each other.

Conclusion

Life's essential 8 was negatively associated with periodontitis, but more prospective trails are needed to confirm our findings.

Periodontal Disease, Tooth Loss, and Systemic Conditions: An Exploratory Study

BACKGROUND

Although systemic medical conditions are associated with periodontitis and tooth loss, large-scale studies that include less prevalent systemic conditions are needed. The purpose of the study was to investigate the link between periodontal disease and tooth loss with systemic medical conditions in a large and diverse population.

METHODS

Dental charts of adult patients who had attended the dental clinics seeking dental therapy of the universities contributing data to the BigMouth network and accepted the protocol of the study were included. Dental Procedure Codes and Current Procedural Terminology procedures were utilised to identify patients with and without periodontitis. Data were extracted from patients' electronic health records including demographic characteristics, dental procedural codes, and self-reported medical conditions as well as the number of missing teeth.

RESULTS

A total of 108,307 records were ultimately included in the analysis; 42,377 of them included a diagnosis of periodontitis. The median age of the included population was 47.0 years, and 55.2% were female. Older and male individuals were significantly more likely to be in the periodontitis group and have higher number of missing teeth. A number of systemic conditions are associated with periodontitis and a higher number of missing teeth. High blood pressure, smoking, drug use, and diabetes were all found to be significant. Other significant conditions were anaemia, lymphoma, glaucoma, dialysis, bronchitis, sinusitis hepatitis, and asthma.

CONCLUSIONS

Within the limitations of this retrospective study that utilised the BigMouth dental data repository, the association of a number of systemic conditions such as smoking, diabetes, and hypertension with periodontitis and tooth loss has been confirmed. Additional connections have been highlighted for conditions that are not commonly reported in the literature.

Hemophore-like proteins of the HmuY family in the oral and gut microbiome: unraveling the mystery of their evolution

SUMMARY

Heme (iron protoporphyrin IX, FePPIX) is the main source of iron and PPIX for host-associated pathogenic bacteria, including members of the Bacteroidota (formerly Bacteroidetes) phylum. Porphyromonas gingivalis, a keystone oral pathogen, uses a unique heme uptake (Hmu) system, comprising a hemophore-like protein, designated as the first member of the novel HmuY family. Compared to classical, secreted hemophores utilized by Gram-negative bacteria or near-iron transporter domain-based hemophores utilized by Gram-positive bacteria, the HmuY family comprises structurally similar proteins that have undergone diversification during evolution. The best characterized are P. gingivalis HmuY and its homologs from Tannerella forsythia (Tfo), Prevotella intermedia (PinO and PinA), Bacteroides vulgatus (Bvu), and Bacteroides fragilis (BfrA, BfrB, and BfrC). In contrast to the two histidine residues coordinating heme iron in P. gingivalis HmuY, Tfo, PinO, PinA, Bvu, and BfrA preferentially use two methionine residues. Interestingly, BfrB, despite conserved methionine residue, binds the PPIX ring without iron coordination. BfrC binds neither heme nor PPIX in keeping with the lack of conserved histidine or methionine residues used by other members of the HmuY family. HmuY competes for heme binding and heme sequestration from host hemoproteins with other members of the HmuY family to increase P. gingivalis competitiveness. The participation of HmuY in the host immune response confirms its relevance in relation to the survival of P. gingivalis and its ability to induce dysbiosis not only in the oral microbiome but also in the gut microbiome or other host niches, leading to local injuries and involvement in comorbidities.

Shared genetic architecture between periodontal disease and type 2 diabetes: a large scale genome-wide cross-trait analysis

PURPOSE

To investigate the relationship between abnormal glucose metabolism, type 2 diabetes (T2D), and periodontal disease (PER) independent of Body Mass Index (BMI), we employed a genome-wide cross-trait approach to clarify the association.

METHODS

Our study utilized the most extensive genome-wide association studies conducted for populations of European ancestry, including PER, T2D, fasting glucose, fasting insulin, 2-hour glucose after an oral glucose challenge, HOMA-β, HOMA-IR (unadjusted or adjusted for BMI) and HbA1c.

RESULTS

With this approach, we were able to identify pleiotropic loci, establish expression-trait associations, and quantify global and local genetic correlations. There was a significant positive global genetic correlation between T2D (rg = 0.261, p = 2.65 × 10-13), HbA1c (rg = 0.182, p = 4.14 × 10-6) and PER, as well as for T2D independent of BMI (rg = 0.158, p = 2.34 × 10-6). A significant local genetic correlation was also observed between PER and glycemic traits or T2D. We also identified 62 independent pleiotropic loci that impact both PER and glycemic traits, including T2D. Nine significant pathways were identified between the shared genes between T2D, glycemic traits and PER. Genetically liability of HOMA-βadjBMI was causally associated with the risk of PER.

CONCLUSION

Our research has revealed a genetic link between T2D, glycemic traits, and PER that is influenced by biological pleiotropy. Notably, some of these links are not related to BMI. Our research highlights an underlying link between patients with T2D and PER, regardless of their BMI.

Effect of conventional and self-ligating brackets on periodontal health. Systematic review and meta-analysis

Background

To compare the effect of conventional brackets and self-ligating brackets on periodontal health.

Material and Methods

A search of information up to October 2022 was carried out in the following electronic databases: PubMed/MEDLINE, Cochrane Library, Scopus, Web of Science (WoS), EMBASE, SciELO and Google Scholar. We included studies that were randomised clinical trials, dealing with conventional brackets and self-ligating brackets and their effect on periodontal health, with no language restriction and no time limit. The Risk of Bias 2 (Rob 2.0) tool was used to determine the risk of bias of the included studies. The information selected from the studies was entered and analysed with RevMan 5.3, using the mean and standard deviation with a 95% confidence interval as a measure. Finally, an analysis was performed using the GRADE system to classify the quality of the evidence and grade the strength of the recommendation.

Results

The preliminary search yielded a total of 399 articles, discarding those that did not meet the selection criteria, leaving only 13 articles. The effect of conventional and self-ligating brackets on periodontal health was determined using periodontal probing depth (PPD), plaque index (PI), gingival index (GI) and bleeding index (BI), showing advantages of self-ligating brackets in PI and BI, and no differences compared to self-ligating brackets in PPD and GI.

Conclusions

Self-ligating brackets probably better preserve periodontal health compared to conventional brackets regarding plaque accumulation and bleeding on probing. Key words:Conventional brackets, self-ligating brackets, periodontal health, orthodontic treatment, systematic review, meta-analysis.

Causal Association Analysis of Periodontitis and Inflammatory Bowel Disease: A Bidirectional Mendelian Randomization Study

BACKGROUND

Periodontitis has been reported to be associated with inflammatory bowel disease (IBD), including ulcerative colitis (UC), and Crohn's disease (CD). However, the causality of these 2 diseases remains unclear. We conducted bidirectional Mendelian randomization (MR) to investigate the causal relationship between periodontitis and IBD.

METHODS

We obtained the genome-wide association study (GWAS) summary data of European populations from FinnGen database (for IBD) and a published article (for periodontitis), from which independent single nucleotide polymorphisms were selected as instrumental variables. Inverse variance-weighted (IVW), MR-Egger, and weighted median (WM) methods were utilized for MR analysis. Heterogeneity or pleiotropy was detected through Cochran's Q test and MR-Egger intercept, respectively. Outlier was identified with MR-PRESSO (Mendelian Randomization Pleiotropy RESidual Sum and Outlier) and leave-one-out analysis. All statistical analyses were performed with R 4.2.1 and the packages of TwoSampleMR version 0.5.6.

RESULTS

Genetic prediction showed that periodontitis was the risk factor of UC (odds ratio [OR], 1.13; 95% confidence interval [CI], 1.01-1.26; P = .027), rather than of CD (OR, 0.92; 95% CI, 0.74-1.15; P = .456) and IBD (OR, 0.96; 95% CI, 0.81-1.13; P = .619). To the contrary, CD, not UC or IBD, resulted in exacerbating periodontitis in terms of the results of the IVW (OR, 1.09; 95% CI, 1.01-1.17; P = .021) and WM (OR, 1.10; 95% CI, 1.01-1.20; P = .030) methods. Heterogeneity or pleiotropy was acceptable.

CONCLUSIONS

Our results indicated that CD was the risk factor for periodontitis; conversely, periodontitis was responsible for the exacerbation of UC, enhancing the existence of mouth-gut axis. Patients with UC should pay more attention to periodontal health, while patients with periodontitis should actively pay close heed to intestinal health.

Tooth loss is associated with prevalent diabetes and incident diabetes in a longitudinal study of adults in Ireland

AIM

The aim of this study was to explore the relationship between periodontal status, tooth loss and diabetes among community-dwelling adults aged 50 years and over in Ireland.

METHODS

From respondents who attended a health assessment in Wave 3 of the Irish Longitudinal Study on Ageing (TILDA), an opportunistic sample was selected for an oral health examination. The oral health examination criteria were used in previous Irish surveys and WHO recommendations. For diabetes, the self-reported and objectively measured data on diabetes for the same cohort from Wave 3 to Wave 5 of TILDA was used. Multinomial regression analysis was used to evaluate the relationship between diabetes and tooth loss and tooth loss and incident diabetes, controlling for other covariates.

RESULTS

Out of the 3111 people who were offered an oral health assessment 2539 were examined. For the purposes of analysis, the adults below 50 years of age (n = 31) and those with an incomplete oral health assessment (n = 4) were omitted from the sample. The final sample consisted of 2504 people, giving a response rate of 80.5%. Among the study sample, 9.9% (n = 249) were edentate; 35.7% (n = 895) had 1-19 teeth and 54.4% (n = 1360) had ≥20 teeth. From the sample of 2504 adults, 2358 had HbA1c results and 8.4% (n = 198) of these had diabetes according to the TILDA criteria. Multinomial regression analysis showed that diabetes was associated with tooth loss. Diabetes at Wave 3 was associated with a higher rate of being edentate (PR 2.12, 95% CI 1.27-3.52) relative to having ≥20 teeth while controlling for the effect of age, gender, education level, area of residence, body mass index (BMI) and smoking. Furthermore, having 1-19 teeth at Wave 3 was associated with incident diabetes over a 4-year follow-up (OR 1.94, 1.00-3.75). There was no evidence of an association between diabetes and periodontal status as measured in this sample.

CONCLUSION

The results suggested that diabetes was associated with tooth loss and that this relationship may be bi-directional among community-dwelling adults aged 50 years and over in Ireland, but they do not support a relationship between diabetes and periodontal status in this sample.

Genetic causal association between rheumatoid arthritis and periodontitis: a bidirectional two-sample Mendelian randomization analysis

BACKGROUND

A link between rheumatoid arthritis (RA) and periodontitis (PD) has been established. However, their causal relationship remains unclear and the effect of different serotypes of RA on the PD development has not been investigated. This study aims to elucidate the causal association between PD and different serotypes of RA using Mendelian randomization (MR).

METHODS

A bidirectional two-sample MR analysis was performed using available large-scale genome-wide association studies statistics. The inverse-variance weighted (IVW) or multiplicative random-effects IVW was used to determine causality, depending on the heterogeneity of instrumental variables. Additional sensitivity analyses were also performed.

RESULTS

The forward MR analysis identified that seropositive RA (odds ratio (OR), 1.26; 95% confidence interval (CI), 1.07-1.44; p = 0.0018), but not seronegative RA (OR, 1.01; 95% CI, 0.95-1.06; p = 0.9098), was associated with an increased risk of PD. The reverse MR analysis did not show any significant causal effect of PD on RA, independent of the serotypes. The sensitivity tests (p > 0.05) confirmed the robustness and accuracy of these findings.

CONCLUSION

This study revealed that there was a genetic causal effect of seropositive RA on PD, suggesting that this subtype of RA patients may require specific clinical attention to prevent the development of PD.

Prevalence and Severity of Periodontal Disease and its Association with Type-II Diabetes Mellitus and Smoking by Using Periodontal Screening and Recording: A Retrospective Study

Background

Periodontal screening recording (PSR) is considered a quick, reliable, reproducible valuable screening tool for periodontal disease. This study aims to find the prevalence and severity of periodontal disease and its association with self-reported diabetic status and smoking history of the patients by using PSR codes over a period of 2 years.

Material and Methods

This was a cross-sectional retrospective study in a dental hospital in Chandigarh. Data of 10,882 patients comprising self-reported history of smoking (893) and diabetes (725) patients were assessed for the prevalence of periodontal disease by using PSR codes. Pearson Chi-Square test was used for statistical evaluation of PSR codes data.

Results

Out of a total of 65,292 sextants assessed, the maximum and minimum reported PSR codes were 2 and 4, respectively. Gingivitis was found to be the most prevalent, followed by periodontitis and periodontal health in the total assessed population (P < 0.001). Mucogingival problems and complete edentulism were found to be more prevalent in posterior sextants in comparison to anterior sextants. Both self-reported smokers and type-II diabetes mellitus patients presented gingivitis as the most common clinical presentation, with the highest prevalence seen in the 55-74-year age group, which also comprised the group with maximum mucogingival problems and edentulism.

Conclusion

This study gives an overview of patients' general oral health status and reflects the burden of periodontal disease in the Chandigarh region, thus contributing to the national oral health data.

Periodontitis and the incidence of metabolic syndrome: An 8-year longitudinal study of an adult Japanese cohort

AIM

To examine the effect of periodontitis on the development of metabolic syndrome (MetS) and MetS components.

MATERIALS AND METHODS

This study included 4761 participants aged 30-74 years who underwent health examinations at both baseline and 8-year follow-up. The Japanese MetS criteria were used for diagnosis. The Community Periodontal Index was used to assess periodontal status. The association between periodontal status and MetS incidence was examined by Poisson regression analysis.

RESULTS

Multivariate analysis revealed that individuals with a ≥6 mm periodontal pocket had a significantly higher relative risk (RR) for MetS onset, as compared to individuals without deep periodontal pockets (adjusted RR 1.30, 95% confidence interval [CI]: 1.01-1.67). Compared to individuals without a deep periodontal pocket, individuals with a ≥6 mm periodontal pocket had significantly higher RRs for developing two components of MetS; the RRs were 1.25 (95% CI: 1.01-1.56) for abdominal obesity and 1.39 (95% CI: 1.03-1.86) for hyperglycaemia.

CONCLUSIONS

Individuals with periodontitis had a significantly higher risk of MetS onset, possibly due to the influence of periodontitis on abdominal obesity and hyperglycaemia.

Establishment of models to predict factors influencing periodontitis in patients with type 2 diabetes mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) is associated with periodontitis. Currently, there are few studies proposing predictive models for periodontitis in patients with T2DM.

AIM

To determine the factors influencing periodontitis in patients with T2DM by constructing logistic regression and random forest models.

METHODS

In this a retrospective study, 300 patients with T2DM who were hospitalized at the First People's Hospital of Wenling from January 2022 to June 2022 were selected for inclusion, and their data were collected from hospital records. We used logistic regression to analyze factors associated with periodontitis in patients with T2DM, and random forest and logistic regression prediction models were established. The prediction efficiency of the models was compared using the area under the receiver operating characteristic curve (AUC).

RESULTS

Of 300 patients with T2DM, 224 had periodontitis, with an incidence of 74.67%. Logistic regression analysis showed that age [odds ratio (OR) = 1.047, 95% confidence interval (CI): 1.017-1.078], teeth brushing frequency (OR = 4.303, 95%CI: 2.154-8.599), education level (OR = 0.528, 95%CI: 0.348-0.800), glycosylated hemoglobin (HbA1c) (OR = 2.545, 95%CI: 1.770-3.661), total cholesterol (TC) (OR = 2.872, 95%CI: 1.725-4.781), and triglyceride (TG) (OR = 3.306, 95%CI: 1.019-10.723) influenced the occurrence of periodontitis (P < 0.05). The random forest model showed that the most influential variable was HbA1c followed by age, TC, TG, education level, brushing frequency, and sex. Comparison of the prediction effects of the two models showed that in the training dataset, the AUC of the random forest model was higher than that of the logistic regression model (AUC = 1.000 vs AUC = 0.851; P < 0.05). In the validation dataset, there was no significant difference in AUC between the random forest and logistic regression models (AUC = 0.946 vs AUC = 0.915; P > 0.05).

CONCLUSION

Both random forest and logistic regression models have good predictive value and can accurately predict the risk of periodontitis in patients with T2DM.

Assessing the Antioxidant Benefits of Topical Carvacrol and Magnolol Periodontal Hydrogel Therapy in Periodontitis Associated with Diabetes in Wistar Rats

It is well recognized that oxidative stress contributes to chronic stress-induced cytotoxicity, which is a major factor in the progression of many diseases, including periodontitis and diabetes. Formulas based on natural extracts with antioxidant properties are alternative treatment perspectives in the management of such diseases. The aim of our study was to assess how carvacrol and magnolol influence periodontitis associated with diabetes in Wistar rats. Ninety Wistar rats were distributed in nine groups: I-control group; II-diabetes group (D); III-periodontitis group (P); IV-periodontitis and diabetes group (PD); V-periodontitis and diabetes with vehicle alone (PDV); VI-periodontitis and diabetes treated with carvacrol (PDC); VII-periodontitis and diabetes treated with magnolol (PDM); VIII-periodontitis and diabetes treated with carvacrol and magnolol (PDCM); IX-healthy group with vehicle alone (CV). Blood malondialdehyde (MDA) levels and catalase activity levels (CAT) were measured as indicators of oxidative stress and antioxidant capacity, respectively. Where diabetes and periodontitis were induced, MDA was augmented and CAT was depleted significantly. Whether given alone (PDM) or in combination with carvacrol (PDCM), magnolol significantly decreased MDA. Between the PDM group and the PDCM group, there were no notable differences. In Wistar rats with periodontitis related to diabetes, topical use of hydrogels containing magnolol, either alone or in combination with carvacrol, may reduce oxidative stress.

The Association between Tooth Loss and Insulin Resistance Mediated by Diet Quality and Systemic Immunoinflammatory Index

(1) Background: Both tooth loss and diabetes have high global prevalence, and both have a significant influence on patients' general health and quality of life. Previous research has indicated a possible connection between tooth loss and diabetes, but it has been unclear whether tooth loss has an effect on the development of diabetes and how it affects it. We aim to investigate the relationship between insulin resistance (IR) and tooth loss and examine how the systemic immune-inflammation index (SII) level and diet quality mediate it. (2) Methods: The cross-sectional study data were obtained from the National Health and Nutrition Examination Survey (NHANES). After describing and comparing baseline data, we used regression models to evaluate the relationship between IR and tooth loss, diet quality and tooth loss and IR, SII and tooth loss and IR. Furthermore, we applied bootstrapping to test the mediation effect of diet quality and SII between tooth loss and IR. Diet quality is reflected by the HEI (Healthy Eating Index)-2015 score. (3) Results: The total number of subjects included was 8197, with 3861 individuals belonging to the IR group (HOMA-IR ≥ 2.5) and 4336 in the non-IR group (HOMA-IR < 2.5). In the model with all covariates adjusted, tooth loss in the fourth quartile was found to be positively correlated with an increase in HOMA-IR (OR = 1.301; 95% confidence interval (CI) = [1.102, 1.537]; p < 0.001) compared to the first quartile; tooth loss in the fourth quartile correlated with the HEI-2015 score compared to the first quantile (β = -0.121, 95% CI = [-4.839, -2.974], p < 0.001); and the highest number of tooth loss was found to have a significant effect on SII (β = 0.032; 95%CI = [1.777, 47.448]; p < 0.05). Compared to average diet quality, best diet quality acts as a safeguard against elevated HOMA-IR (OR = 0.776; 95% CI = [0.641, 0.939]; p < 0.01); inadequate diet quality is a risk factor (OR = 1.267; 95%CI = [1.138, 1.411]; p < 0.001) conversely. Meanwhile, it can be seen that compared with the first quantile of SII, the highest score is significantly correlated with the higher incidence of IR (OR = 1.363; 95%CI = [1.179, 1.575]; p < 0.001). Diet quality and SII played a partial mediating role in the relationship between HOMA-IR and tooth loss, and the mediating effect ratio for the total effect value was 4.731% and 4.576%, respectively. The mediating effect of SII and diet quality in the association of the relationship between HOMA-IR and tooth loss both was 0.003 (95%CI = [0.001, 0.004]). (4) Conclusions: Our study revealed the relationship between IR and tooth loss, and further explored the mediating role of SII and diet quality between the number of missing teeth and IR, emphasizing that improving diet quality and reducing SII can effectively prevent and treat IR and related diseases. It provides new theoretical support for the study of IR mechanisms and new ideas and approaches to deal with related diseases.

Improving Patient Well-Being as a Broader Perspective in Dentistry

Patient well-being encompasses the physical, mental, psychological, and social health of an individual. To adequately treat an individual and increase their quality of life, whole-person, patient-centred care needs to be utilised. This review aims to concisely summarise ways to improve patients' well-being through and in dentistry. Oral health is tied to one's quality of life through oral function, overall health, self-perception, social acceptance, and social interaction. These relationships demonstrate the importance of utilising oral health to increase patient quality of life, unify health professions in patient treatment, use preventative medicine, and empower patients about their health. To do so, the dental profession can increase the scope of practice to provide preventative health screening and education on general health, have more open communication, collaborate with other health care professionals, and have broader consultations. This will allow for better continuity of care and shift the focus of treatment to the whole person instead of a symptom. Whilst there are barriers that need to be resolved and cost feasibility requires more exploration, the potential benefit to patients is apparent.

Disruption of cholesterol homeostasis triggers periodontal inflammation and alveolar bone loss

Oral diseases exhibit a significant association with metabolic syndrome, including dyslipidemia. However, direct evidence supporting this relationship is lacking, and the involvement of cholesterol metabolism in the pathogenesis of periodontitis (PD) has yet to be determined. In this study, we showed that high cholesterol caused periodontal inflammation in mice. Cholesterol homeostasis in human gingival fibroblasts was disrupted by enhanced uptake through C-X-C motif chemokine ligand 16 (CXCL16), upregulation of cholesterol hydroxylase (CH25H), and the production of 25-hydroxycholesterol (an oxysterol metabolite of CH25H). Retinoid-related orphan receptor α (RORα) mediated the transcriptional upregulation of inflammatory mediators; consequently, PD pathogenesis mechanisms, including alveolar bone loss, were stimulated. Our collective data provided direct evidence that hyperlipidemia is a risk factor for PD and supported that inhibition of the CXCL16-CH25H-RORα axis is a potential treatment mechanism for PD as a systemic disorder manifestation.

A Survey of Oral Assessment and Healthcare Education at Nursing Schools in Japan

OBJECTIVES

This study aimed to investigate the performance of oral assessment and health care education at nursing schools across Japan to identify problems and the need for oral health professional support.

METHODS

The participants were the academic staff in charge of oral health care education in the basic, adult, gerontological, and home nursing fields of 295 schools in Japan that offered a bachelor's degree in nursing. A questionnaire was sent to 1180 heads of the nursing fields of these schools. They were requested to have oral health care educators complete the survey; data on the performance of oral assessment and health care education and human resources allocated were collected through a questionnaire.

RESULTS

A total of 311 (26%) questionnaires were returned, 196 (63%) of which were completed by oral health care educators. Regarding the performance of oral assessment education, the majority (71%) of them spent less than 2 hours in teaching, and only 24.5% taught the usage of oral assessment tools. Regarding the performance of oral health care education, more than 90% spent less than 2 hours in lecture-based and practical oral health care education, respectively. Less than half taught the association of periodontal diseases with diabetes and cardiovascular diseases and use of fluoride for caries prevention in the lectures, and only approximately 30% taught the usage of an interspace brush or dental floss. Moreover, less than 10% of oral health professionals taught oral health care in lectures or practical oral health care.

CONCLUSIONS

This study revealed problems associated with oral assessment and health care education in Japanese nursing schools. To address these, support from oral health care professionals is required. Further studies are also required to reveal problems in oral assessment and health care education in other nursing schools that do not offer a bachelor's degree programme in Japan and other countries.

Clostridium butyricum MIYAIRI 588 alleviates periodontal bone loss in mice with diabetes mellitus

The gut microbiota is a bridge linking periodontitis and systemic diseases, such as diabetes mellitus (DM). The probiotic Clostridium butyricum MIYAIRI 588 (CBM588) is reportedly an effective therapeutic approach for gut dysbiosis. Here, in a mouse model, we explored the therapeutic effect of CBM588 on periodontal bone destruction in DM and DM-associated periodontitis (DMP), as well as the underlying mechanism. Micro-computed tomography revealed that DM and DMP both aggravated periodontal bone destruction, which was alleviated by intragastric supplementation with CBM588. Moreover, 16S rRNA sequencing and untargeted metabolite analysis indicated that CBM588 ameliorated DMP-triggered dysbiosis and led to reduced oxidative stress associated with elevated 4-hydroxybenzenemethanol (4-HBA) in serum. Furthermore, in vitro and in vivo experiments found that the metabolite 4-HBA promoted nuclear factor erythroid 2-related factor 2 (Nrf2) signaling activation and modulated the polarization of macrophages, thus ameliorating inflammatory bone destruction in DMP. Our study demonstrates the protective effects of CBM588 in DM-induced mice, with and without ligature-induced periodontitis. The mechanism involves regulation of the gut microbiota and restoration of the integrity of the gut barrier to alleviate oxidative damage by elevating serum 4-HBA. This study suggests the possibility of CBM588 as a therapeutic adjuvant for periodontal treatment in diabetes patients.

Oral health and type 2 diabetes in a socioeconomic perspective

AIMS

This study aimed to examine the association between type 2 diabetes and poor self-rated oral health, and to investigate whether such association is modified by socioeconomic position.

METHODS

We conducted a cross-sectional study, including a population aged 18-75 years with self-reported type 2 diabetes (N = 41,884) and a sex-, age- and municipality-matched reference population from the Health in Central Denmark survey (2020). Multivariable logistic regression was used, and effect modification of indicators of socioeconomic position was examined.

RESULTS

Oral health was rated as poor in 37.0% of the population with type 2 diabetes and in 23.8% of the reference population without diabetes. Individuals with diabetes had higher risk of poor oral health (adjusted odds ratio (OR) 1.46 (95% CI: 1.39; 1.53)) than references. Interaction was seen between type 2 diabetes and highest attained education (p < 0.001). Stratified analyses showed higher risk of poor oral health in people with type 2 diabetes across all educational levels.

CONCLUSIONS

People with type 2 diabetes were more likely to rate their oral health as poor than the reference population. Low education strengthened the association between diabetes and poor oral health.

Proteomic profile of human gingival crevicular fluid reveals specific biological and molecular processes during clinical progression of periodontitis

BACKGROUND AND OBJECTIVE

There is no clear understanding of molecular events occurring in the periodontal microenvironment during clinical disease progression. Our aim was to explore qualitative and quantitative differences in gingival crevicular fluid (GCF) protein profiles from patients diagnosed with periodontitis between non-progressive and progressive periodontal sites.

METHODS

Five systemically healthy patients diagnosed with periodontitis were monitored weekly in their progression of the disease and GCF samples from 10 candidate sites were obtained. Two groups of five sites, matched from an equal number of teeth, were selected from the five patients: Progression (PG) and Non-Progression (NP). Global protein identification was performed with high-throughput proteomic approaches and label-free analysis determined their relative abundances. Proteins were identified by Proteome Discoverer v2.4 and searched against human SwissProt protein databases. Enrichment bioinformatic analyses were performed in STRING-DB and ShinyGO environment.

RESULTS

1504 and 1500 proteins were identified in NP and PG respectively. Forty-eight proteins were exclusively identified in PG, while 52 were identified in NP. Moreover, 35 proteins were more abundant in PG and 29 proteins in NP (twofold change, p < .05). The NP group was mainly represented by proteins from "response to biotic stimuli and other organisms," "processes of cell death regulation," "peptidase regulation," "protein ubiquitination," and "ribosomal activity" GO categories. The most represented GO categories of the PG group were "assembly of multiprotein complexes," "catabolic processes," "lipid metabolism," and "binding to hemoglobin and haptoglobin."

CONCLUSIONS

There are quantitative and qualitative differences in the proteome of GCF from periodontal sites according to the status of clinical progression of periodontitis. Progressive periodontitis sites are characterized by a protein profile associated with catabolic processes, immune response, and response to cellular stress, while stable periodontitis sites show a protein profile mainly related to wound repair and healing processes, cell death regulation, and chaperone-mediated autophagy. Understanding the etiopathogenic role of these profiles in progressive periodontitis may help to develop new diagnostic and therapeutic approaches.

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

INTRODUCTION

The aim of this review is to examine and quantify the long-term risk of immune-mediated systemic conditions in people with periodontitis compared to people without periodontitis.

METHODS

Medline, EMBASE and Cochrane databases were searched up to June 2022 using keywords and MeSH headings. The 'Risk of Bias in Non-Randomised Studies of Interventions' tool was used to assess bias. Cohort studies comparing incident metabolic/autoimmune/inflammatory diseases in periodontitis to healthy controls were included. Meta-analysis and meta-regression quantified risks and showed impact of periodontitis diagnosis type and severity.

RESULTS

The search retrieved 3354 studies; 166 studies were eligible for full-text screening, and 30 studies were included for review. Twenty-seven studies were eligible for meta-analysis. The risks of diabetes, rheumatoid arthritis (RA) and osteoporosis were increased in people with periodontitis compared to without periodontitis (diabetes-relative risk [RR]: 1.22, 95% CI: 1.13-1.33; RA-RR: 1.27, 95% CI: 1.07-1.52; osteoporosis-RR: 1.40, 95% CI: 1.12-1.75). Risk of diabetes showed gradient increase by periodontitis severity (moderate-RR = 1.20, 95% CI = 1.11-1.31; severe-RR = 1.34, 95% CI = 1.10-1.63).

CONCLUSION

People with moderate-to-severe cases of periodontitis have the highest risk of developing diabetes, while the effect of periodontal severity on risk of other immune-mediated systemic conditions requires further investigation. More homologous evidence is required to form robust conclusions regarding periodontitis-multimorbidity associations.

Association between Periodontitis and HbA1c Levels in Non-Diabetic Patients: A Systematic Review and Meta-Analysis

BACKGROUND

A high detection rate of diabetes among dental visitors has been reported recently. This systematic review aimed to evaluate the association between periodontitis and glycated hemoglobin (HbA1c) levels among non-diabetic individuals.

METHODS

The EMBASE, MEDLINE, Web of Science, Cochrane Library, PubMed, and Open GREY databases were searched, and observational studies published until 1st June 2023 were identified. A methodological quality assessment was conducted based on the original and modified versions of the Newcastle-Ottawa scale. Cohort, case-control, and cross-sectional studies that performed clinical periodontal examinations and measured HbA1c levels in non-diabetic adults were included. A meta-analysis was conducted to estimate the weighted mean difference (WMD) between individuals with and without periodontitis.

RESULTS

In total, 29 case-control and 5 cross-sectional studies were selected from 2583 potentially eligible articles. Among them, sixteen case-control and three cross-sectional studies with moderate to high quality were selected for the meta-analyses. The HbA1c levels in periodontitis patients were significantly higher than those in individuals with healthy periodontal conditions (WMD = 0.16; p < 0.001) among the non-diabetic populations.

CONCLUSIONS

This study reveals a significant association between periodontitis and HbA1c levels in non-diabetic populations. Thus, HbA1c screening may be recommended to detect potential hyperglycemia in non-diabetic periodontitis patients.

The bidirectional relationship between periodontitis and diabetes: New prospects for stem cell-derived exosomes

Periodontitis and diabetes have a bidirectional link, making therapeutic treatment of periodontitis and diabetes challenging. Numerous factors, including microbes, inflammatory cytokines, immune cell activity, glucose levels, and metabolic disorders, contribute to the bidirectional relationship of periodontitis and diabetes. Basic periodontal treatment, medication, surgical treatment, and combined treatment are the most widely used treatments, but their efficacy are limited. Because of their capacity to support bone remodeling and tissue regeneration and restoration, reduce blood glucose levels, restore islet function, and ameliorate local and systemic inflammation, stem cell-derived exosomes have emerged as a possible therapeutic. In this review, we summarize the utilization of stem cell-derived exosomes in periodontitis and diabetes，discuss their potential mechanisms in periodontitis and diabetes bidirectional promoters. It provides some theoretical basis for using stem cell-derived exosomes to regulate the bidirectional link between periodontitis and diabetes.

Teeth Rehabilitation and Nutritional Influence on Diabetic Patients: A Review

Diabetes mellitus (DM) is a globally prevalent endocrine and metabolic disorder characterized by hyperglycemia. Its complications significantly impact both the quality and longevity of the patient's life with a substantial burden on the healthcare system. Missing teeth make individuals more susceptible to malnutrition compared to those with functional teeth. This is especially true for people with diabetes, as the condition is closely linked to both oral health and food intake. Natural teeth loss can significantly reduce an individual's ability to chew food, leading to a decrease in the quality and quantity of their nutrition. Prosthodontics is a dental specialty that replaces missing teeth with artificial ones. Replacing missing teeth may prevent the risk of malnutrition due to decreased ability to chew. Good oral health is important for overall health, especially for those with conditions such as diabetes. Artificial teeth replacement may improve nutrition intake by improving chewing ability. Therefore, the ultimate objective of rehabilitating a patient's oral cavity is to replace the shape and function in terms of chewing performance to a degree that is as close to normal as feasible. The purpose of this review is to explore the literature showing the link between natural teeth loss and nutrition in individuals with DM, with a special focus on prosthodontic management. Several oral complications occur in diabetic patients specifically teeth loss, which in turn affects mastication function. This in turn cause malnutrition and affect glucose level. It is imperative for healthcare providers to take an interdisciplinary approach in order to improve the dental and nutritional status and overall well-being of DM patients.

Effect of Non-Surgical Periodontal Therapy on Systemic Inflammatory Markers, Glycemic Status and Levels of Proteinuria in Type 2 Diabetic and Non-Diabetic Patients With Chronic Periodontitis

AIMS AND OBJECTIVES

 The present study aimed to evaluate the effect of non-surgical periodontal therapy (NSPT) on systemic inflammatory markers, glycemic status, and levels of proteinuria in Type 2 diabetic and non-diabetic individuals with chronic periodontitis.

METHODOLOGY

A total of 120 patients, categorized into three groups of 40 each, were included in this randomized observational study. Group 1 comprised patients with chronic periodontitis; Group 2 had chronic periodontitis with controlled diabetes; and Group 3 represented patients with chronic periodontitis with uncontrolled diabetes based on fasting blood sugar (FBS) and glycated hemoglobin (HbA1c) levels. Periodontal clinical parameters like plaque index, gingival index, bleeding on probing, pocket depth, and clinical attachment levels were evaluated. Blood samples and urine samples were collected and assessed for the levels of FBS, HbA1c, total protein, albumin, globulin, and proteinuria. All parameters recorded at baseline and three months after non-surgical periodontal therapy were analyzed for statistical significance at p <.05 using SPSS Inc. Released 2007. SPSS for Windows, Version 16.0. Chicago, SPSS Inc.

RESULTS

A significant reduction in the periodontal clinical parameters within the groups, except for the clinical attachment level in Group 1 patients (p = 0.05), was observed. Glycemic status revealed a significant reduction after non-surgical periodontal therapy (p < 0.001), and on intragroup comparison, the total protein, albumin, globulin, and microprotein blood and urine levels showed significance among the evaluated groups (p < 0.001).

CONCLUSION

Non-surgical periodontal treatment can effectively improve the periodontal and circulating inflammatory status. Results of our study showed improved glycemic control and a reduction in systemic inflammatory markers and proteinuria after performing non-surgical periodontal treatment in patients with type 2 diabetes.

Does periodontitis affect respiratory health?

DATA SOURCES

PubMed, Scopus and Cochrane Library were systematically searched for studies published up to October 2021.

STUDY SELECTION

Two separate search strategies were employed: (1) In adults with periodontitis, what is the prevalence or incidence of respiratory diseases compared to healthy or gingivitis adults in cross-sectional, cohort or case -control studies. (2) In adults with periodontitis and respiratory disease, what are the effects of periodontal therapy compared to no or minimal therapy in clinical trials (randomised and non-randomised)? Respiratory diseases were defined as chronic obstructive pulmonary disease (COPD), obstructive sleep apnoea (OSA), asthma, COVID-19, and community acquire pneumonia (CAP). Exclusion criteria included non-English studies, individuals with severe systemic comorbidities, less than 12 months follow up, and a sample size less than 10 individuals.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently screened the titles, abstracts, and selected manuscripts against the inclusion criteria. Disagreement was solved by consulting a third reviewer. Studies were classified according to the respiratory diseases investigated. Quality assessment was performed using various tools. Qualitative assessment was performed. Studies with sufficient data were included in meta-analyses. Heterogeneity was assessed using the Q test and I2 index. Fixed and random effects models were used. Effect sizes were presented as odds-ratios, relative risks, and hazard ratios.

RESULTS

75 studies were included. Meta-analyses revealed statistically significant positive associations of periodontitis with COPD and OSA (p < 0.001) however no association for asthma. Four studies showed positive effects of periodontal treatment on COPD, asthma, and CAP.

Bidirectional associations between periodontal disease and systemic diseases: a nationwide population-based study in Korea

To evaluate the associations of periodontal disease (PD) with systemic diseases, including diabetes mellitus (DM) and cardiovascular disease (CVD), as well as the reciprocal association. The CVD included the cases of coronary heart disease and heart failure. A prospective study was conducted from 2007 to 2019 using linked data from three databases in Korea. Three separate study groups were formed to individually determine the risks of PD (n = 10,533), DM (n = 14,523) and CVD (n = 14,315). All diseases were confirmed based on physicians' diagnoses using medical records and self-reports. Cox proportional hazard regression was applied with 95% confidence intervals (CIs) to obtain hazard ratios (HRs). PD was significantly associated with an elevated risk of DM (HR [95% CI]: 1.22 [1.07-1.39]) after full adjustment for age, sex, lifestyle factors, body mass index, dental behaviour and CVD. PD was also found to increase the risk of CVD (1.27 [1.03-1.57]), whereas CVD increased the risk of PD (1.20 [1.09-1.32]) after full adjustment for other covariates including DM. This study found a bidirectional association between PD and CVD, as well as a positive association of PD with DM.

Diabetes mellitus promotes susceptibility to periodontitis-novel insight into the molecular mechanisms

Diabetes mellitus is a main risk factor for periodontitis, but until now, the underlying molecular mechanisms remain unclear. Diabetes can increase the pathogenicity of the periodontal microbiota and the inflammatory/host immune response of the periodontium. Hyperglycemia induces reactive oxygen species (ROS) production and enhances oxidative stress (OS), exacerbating periodontal tissue destruction. Furthermore, the alveolar bone resorption damage and the epigenetic changes in periodontal tissue induced by diabetes may also contribute to periodontitis. We will review the latest clinical data on the evidence of diabetes promoting the susceptibility of periodontitis from epidemiological, molecular mechanistic, and potential therapeutic targets and discuss the possible molecular mechanistic targets, focusing in particular on novel data on inflammatory/host immune response and OS. Understanding the intertwined pathogenesis of diabetes mellitus and periodontitis can explain the cross-interference between endocrine metabolic and inflammatory diseases better, provide a theoretical basis for new systemic holistic treatment, and promote interprofessional collaboration between endocrine physicians and dentists.

Physical activity and the risk of periodontitis: an instrumental variable study

OBJECTIVES

Observational studies suggested an inverse association between physical activity and periodontitis. However, observational studies might be subject to unobserved confounding and reverse causation bias. We conducted an instrumental variable study to strengthen the evidence on the relationship between physical activity and periodontitis.

MATERIALS AND METHODS

We used genetic variants associated with self-reported and accelerometer-assessed physical activity in 377,234 and 91,084 UK Biobank participants, respectively, as instruments. For these instruments, genetic associations with periodontitis were obtained from 17,353 cases and 28,210 controls in the GeneLifestyle Interactions in Dental Endpoints consortium.

RESULTS

We found no evidence for effects of self-reported moderate-to-vigorous physical activity, self-reported vigorous physical activity, accelerometry "average accelerations," and "fraction of accelerations > 425 milli-gravities" on periodontitis. For example, the odds ratio for self-reported moderate-to-vigorous physical activity was 1.07 (95% credible interval: 0.87; 1.34) in Causal Analysis using Summary Effect Estimates. We conducted sensitivity analyses to rule out weak instrument bias and correlated horizontal pleiotropy.

CONCLUSIONS

The study does not support an effect of physical activity on the risk of periodontitis.

CLINICAL RELEVANCE

This study provides little evidence that recommending physical activity would help prevent periodontitis.

Longitudinal association between periodontal condition and glycaemic status in middle-aged adults: A cross-lagged panel analysis

AIM

To investigate the existence of a bidirectional temporal relationship between periodontal condition and glycaemic status.

MATERIALS AND METHODS

This longitudinal study included 2198 participants with mean age 43.4 ± 7.7 years, who underwent dental examinations in Yokohama, Japan, at two time points, 2003-2004 and 2008-2009, at an interval of 5 years. Periodontal condition was assessed by the mean value of probing pocket depth (PPD) and clinical attachment level (CAL). Glycaemic status was assessed by fasting glucose and glycated haemoglobin (HbA1c).

RESULTS

The cross-lagged panel models showed the effect of HbA1c at baseline on mean PPD at follow-up (β = 0.044, p = .039). There was a marginal effect of fasting glucose on the mean PPD (β = 0.037, p = .059). It was similar to the effect of fasting glucose or HbAlc on mean CAL. However, in the opposite direction, no effect of mean PPD or CAL at baseline on fasting glucose or HbAlc at follow-up was identified.

CONCLUSIONS

This study demonstrated a unidirectional relationship between glycaemic status and periodontal condition. The study population, however, had mostly mild periodontitis. Future studies are needed to investigate the effect of periodontal condition on glycaemic status in patients with severe periodontitis.

Oral health literacy, knowledge and perceptions in a socially and culturally diverse population: a mixed methods study

BACKGROUND

Poor oral health literacy has been proposed as a causal factor in disparities in oral health outcomes. This study aims to investigate oral health literacy (OHL) in a socially and culturally diverse population of Australian adults visiting a public dental clinic in Western Sydney.

METHODS

A mixed methods study where oral health literacy was assessed using the Health Literacy in Dentistry scale (HeLD-14) questionnaire and semi-structured interviews explored oral health related knowledge, perceptions and attitudes. Interviews were analysed using a thematic approach.

RESULTS

A sample of 48 participants attending a public dental clinic in Western Sydney was recruited, with a mean age of 59.9 (SD16.2) years, 48% female, 50% born in Australia, 45% with high school or lower education, and 56% with low-medium OHL. A subgroup of 21 participants with a mean age of 68.1 (SD14.6) years, 40% female, 64% born in Australia, 56% with a high school or lower education, and 45% with low-medium OHL completed the interview. Three themes identified from the interviews included 1) attitudes and perceptions about oral health that highlighted a lack of agency and low prioritisation of oral health, 2) limited knowledge and education about the causes and consequences of poor oral health, including limited access to oral health education and finally 3) barriers and enablers to maintaining good oral health, with financial barriers being the main contributor to low OHL.

CONCLUSIONS

Strategies aimed at redressing disparities in oral health status should include improving access to oral health information. The focus should be on the impact poor oral health has on general health with clear messages about prevention and treatment options in order to empower individuals to better manage their oral health.

Current status and factors of periodontal disease among Japanese high school students: a cross-sectional study

INTRODUCTION

This study aimed to investigate the prevalence of periodontal disease and the factors of the disease among high school students.

METHOD

The participants were all students aged 15-18 years (n = 1202) at a high school in Japan. The data on oral health perceptions and behaviours were collected by a questionnaire survey. The prevalence of periodontal disease among them was investigated with the partial community periodontal index (PCPI). A logistic regression analysis was used to identify the factors associated with the PCPI.

RESULTS

A total of 1069 students (88.9%) participated in this study. The prevalence of gingival bleeding, calculus, pocket depth of 4-5 mm, and pocket depth of 6 mm or more were 44.2%, 42.2%, 11.4%, and 1.6%, respectively. Approximately one-third of the students had a fear of dental treatment, and only 28.4% used dental floss. The results of logistic regression analysis, adjusted for sex and school year, showed that not visiting dentists regularly, not using dental floss, brushing teeth for less than 5 min, fear of dental treatment, and drinking sports drinks frequently were positively associated with periodontal conditions.

CONCLUSION

This study identified a high prevalence of periodontal disease among Japanese high school students aged 15-18 years and its risk factors, such as poor oral health behaviours and fear of dental treatment.

Oral health status and risk of incident diabetes: a prospective cohort study of 213,389 individuals aged 45 and over

AIMS

To examine whether simple measures of oral health are associated with incident diabetes.

METHODS

This prospective cohort study linked data from the 45 and Up Study, Australia, to administrative health records. The study participants were 213,389 men and women, aged ≥ 45 years, with no diabetes at baseline. The oral health of participants was assessed by questionnaire. Incident diabetes cases were ascertained based on self-report in follow-up questionnaires, linked data on medical and pharmaceutical claims, and hospitalisation data up until 2019. The association between oral health and incident diabetes were calculated using multivariable cox proportional hazards models.

RESULTS

During 2,232,215 person-years of follow-up, 20,487 (9.6%) participants developed diabetes. Compared with those with ≥20 teeth, the adjusted hazard ratio (aHR) for incident diabetes was 1.12 (95% Confidence Interval (CI): 1.08, 1.17) for 10-19 teeth, 1.20 (1.14, 1.26) for 1-9 teeth and 1.15 (1.09, 1.21) for no teeth. Compared with those with excellent/very good teeth and gums, the aHR for incident diabetes was 1.07 (1.03, 1.12) for fair and 1.13 (1.07, 1.20) for poor teeth and gums.

CONCLUSIONS

Simple measures of oral health were associated with risk of developing diabetes, demonstrating the potential importance of oral health screening for diabetes prevention.

Awareness of physicians and dentists in Serbia about the association between periodontitis and systemic diseases: a cross-sectional study

BACKGROUND

Strong evidence supports the association between periodontitis and certain systemic diseases. The aim of the present study was to evaluate the knowledge of a group of physicians and dentists in Serbia regarding this topic and assess their professional actions to prevent and control both periodontal and systemic diseases.

METHODS

An anonymous self-administered structured questionnaire was sent to the available e-mail addresses of randomly selected healthcare providers working in Serbia. According to the inclusion criteria, general practitioners, specialists, general dentists, and specialists working in government hospitals and private practices in various cities in Serbia were recruited in the study. The questionnaire consisted of 17 questions divided into three parts. The first part recorded the sociodemographic characteristics of participants, the second part included questions about the clinical manifestation and etiology of periodontitis, as well as knowledge of the association between periodontitis and systemic diseases, and the third part included questions about professional procedures for the prevention and control of periodontitis and systemic diseases.

RESULTS

A total of 1301 health participants, 739 (57.8%) physicians and 562 (43.2%) dentists, were included in this cross-sectional study. Most respondents (94.7%) were aware of the association between periodontitis and general health. The highest percentage of respondents associated diabetes mellitus and periodontitis. Factors significantly associated with higher knowledge were female sex (odds ratio [OR], 1.86; 95% confidence interval [CI], 1.37-2.52; p < 0.001) and dental profession (OR, 5.86; 95% CI], 4.03-8.53; p < 0.001). Participants who had higher knowledge score were more likely to ask their patients about gum/systematic health (p < 0.001) and refer them to dentists/physicians (p < 0.001).

CONCLUSIONS

It was concluded that compared to the group of dentists, the group of physicians had less knowledge of the relationship between periodontitis and systemic diseases. The female gender was significantly associated with better knowledge. A better understanding of this topic is associated with better clinical practice.

Obesity as a risk factor for periodontitis - does it really matter?

DATA SOURCES

MEDLINE, Scopus, Web of Science Core Collection and Cochrane Library were systematically searched for studies published between January 2000 and June 2022.

STUDY SELECTION

Case-control, cross-sectional and cohort studies investigating the relationship between obesity (determined using BMI) and periodontitis (diagnosed based on clinical attachment loss and probing pocket depth) in adults between 18 and 70 years. Animal studies and systematic reviews were also included. Exclusion criteria included non-English studies and studies involving participants with poor oral health, pregnancy, menopause, and systemic disease.

DATA EXTRACTION AND SYNTHESIS

Data extracted included study demographic data, study design, age range of participants, sample size, study population, obesity criteria, definition of periodontitis used, tooth loss and bleeding on probing. Two reviewers collected the data and disputes were settled by consulting a third reviewer. Risk of bias was measured using the Newcastle-Ottawa Quality Assessment Scale. Qualitative analysis was performed whilst meta-analysis was not performed.

RESULTS

From 1982 studies initially identified, 15 studies were included in the review. Human studies generally showed a positive association between obesity and periodontitis; however, animal studies showed contrasting results. Risk of bias was low in 7 studies, moderate in 5 studies and high in 3 studies.

CONCLUSIONS

Obesity is positively associated with periodontitis; however, a causal relationship cannot be established.

Is periodontitis associated with the risk of immune-mediated systemic conditions?

AIM

This study evaluates the long-term risk of immune-mediated systemic conditions in individuals with periodontitis compared to those without.

DATA SOURCES

A structured online search was conducted in Medline, Cochrane library, and EMBASE using MeSH terms. All the databases were explored from initiation to June 2022. Reference lists of the eligible studies were hand searched as well.

STUDY SELECTION

Peer-reviewed longitudinal retrospective/prospective cohorts and randomized controlled trials comparing incident metabolic/autoimmune/inflammatory diseases in periodontitis to healthy individuals were deemed eligible. Only studies with a minimum follow-up of one year were included.

DATA EXTRACTION AND SYNTHESIS

The authors checked demographics, data source, exclusion/inclusion criteria, total follow-up duration, disease outcome, and limitations to determine the eligible studies. After assessing the risk of bias for the included studies using the Risk of Bias in Non-Randomized Studies of Interventions (ROBINS-I) tool, the authors used the following measures to quantify the disease outcome: relative risk (RR), odds ratio (OR), and hazard ratio (HR). Systemic conditions were categorized as immune-mediated via disrupted metabolic networks (diabetes, kidney disease, liver disease, metabolic syndrome) or chronic inflammation (inflammatory bowel disease, osteoporosis, RA, psoriasis, Sjogren's syndrome), hence recognized as metabolic or autoimmune/inflammatory diseases, respectively. A random effect meta-analysis was used to synthesize the risk of developing each disease. The authors performed subgroup analysis for periodontitis diagnosis type (self-report/clinically diagnosed) and severity. They also conducted a sensitivity analysis to assess the effect of removing studies that did not adjust for smoking status.

RESULTS

From 3354 studies, 166 full texts were screened. Finally, 30 studies were deemed eligible for the systematic review, of which 27 made it to the meta-analysis. The risks of diabetes, rheumatoid arthritis (RA) and osteoporosis were increased in individuals with periodontitis compared to those without periodontitis (diabetes-relative risk [RR]: 1.22, 95% CI: 1.13-1.33; RA-RR: 1.27, 95% CI: 1.07-1.52; osteoporosis-RR: 1.40, 95% CI: 1.12-1.75). The risk of diabetes showed a gradient increase by periodontitis severity (moderate-RR = 1.20, 95% CI = 1.11-1.31; severe-RR = 1.34, 95% CI = 1.10-1.63).

CONCLUSIONS

People with moderate-to-severe periodontitis have the highest risk of developing diabetes. In contrast, the effect of periodontal severity on the risk of other immune-mediated systemic conditions requires further investigation. More homologous evidence is needed to assess the periodontitis-multimorbidity association further.

A retrospective epidemiological investigation of periodontitis risk and current smoking status based on the number of cigarettes per day and the Fagerström Test for Nicotine Dependence: a preliminary pilot study

PURPOSE

The aim of this study was to investigate the risk of periodontitis according to current smoking status based on the number of cigarettes smoked per day (CPD) and the Fagerström Test for Nicotine Dependence (FTND).

METHODS

All enrolled patients were diagnosed and classified according to the new periodontal classification scheme, and current smoking status was investigated via a self-reported questionnaire. The correlation between smoking status (CPD and FTND) and periodontitis risk (severity of periodontitis and tooth loss due to periodontal reasons) was statistically assessed using Spearman correlation coefficients. Moreover, partial correlation analyses between smoking and periodontal status were performed after adjusting for age, sex, and diabetes mellitus.

RESULTS

Overall, data from 74 men and 16 women (mean age: 48.1±10.8 years) were evaluated. The mean number of missing teeth, CPD, and FTND score were 3.5±5.2, 24.6±15.5, and 3.5±2, respectively. CPD and the FTND were significantly positively correlated with each other (r=0.741, P<0.001). CPD and the FTND were also significantly correlated with the severity of periodontitis (CPD: r=0.457, P<0.05 and FTND: r=0.326, P<0.05) and the number of missing teeth due to periodontal reasons (CPD: r=0.525, P<0.05 and FTND: r=0.480, P<0.05), respectively.

CONCLUSIONS

Within the limitations of this study, both CPD and the FTND were significantly correlated with the severity of periodontitis and the number of periodontally compromised extracted teeth.

Osteoimmunology in Periodontitis and Orthodontic Tooth Movement

PURPOSE OF REVIEW

To review the role of the immune cells and their interaction with cells found in gingiva, periodontal ligament, and bone that leads to net bone loss in periodontitis or bone remodeling in orthodontic tooth movement.

RECENT FINDINGS

Periodontal disease is one of the most common oral diseases causing inflammation in the soft and hard tissues of the periodontium and is initiated by bacteria that induce a host response. Although the innate and adaptive immune response function cooperatively to prevent bacterial dissemination, they also play a major role in gingival inflammation and destruction of the connective tissue, periodontal ligament, and alveolar bone characteristic of periodontitis. The inflammatory response is triggered by bacteria or their products that bind to pattern recognition receptors that induce transcription factor activity to stimulate cytokine and chemokine expression. Epithelial, fibroblast/stromal, and resident leukocytes play a key role in initiating the host response and contribute to periodontal disease. Single-cell RNA-seq (scRNA-seq) experiments have added new insight into the roles of various cell types in the response to bacterial challenge. This response is modified by systemic conditions such as diabetes and smoking. In contrast to periodontitis, orthodontic tooth movement (OTM) is a sterile inflammatory response induced by mechanical force. Orthodontic force application stimulates acute inflammatory responses in the periodontal ligament and alveolar bone stimulated by cytokines and chemokines that produce bone resorption on the compression side. On the tension side, orthodontic forces induce the production of osteogenic factors, stimulating new bone formation. A number of different cell types, cytokines, and signaling/pathways are involved in this complex process. Inflammatory and mechanical force-induced bone remodeling involves bone resorption and bone formation. The interaction of leukocytes with host stromal cells and osteoblastic cells plays a key role in both initiating the inflammatory events as well as inducing a cellular cascade that results in remodeling in orthodontic tooth movement or in tissue destruction in periodontitis.

Prevalence and Associated Factors for Periodontal Disease among Type I and II Diabetes Mellitus Patients: A Cross-Sectional Study

In Saudi Arabia, the prevalence of diabetes mellitus (DM) is high. DM is a risk factor for periodontal disease. The current study aimed to estimate the prevalence and potential associated factors for periodontitis among type I and II DM patients in Abha, Saudi Arabia. A cross-sectional study was conducted among patients with DM who attended the Periodontal Consultant Center at King Khalid University and Aseer Central Hospital, in Abha city, from January 2020 to January 2022. A questionnaire was used to collect relevant data. Patients were assessed for the severity of periodontitis. A total of 499 DM patients were enrolled in this study. The prevalence of periodontitis was 7.4% among type I DM and 46.4% among type II DM patients. The prevalence of periodontitis was significantly associated with age among type I DM patients (p-value = 0.001) and type II DM patients (p-value = 0.001), respectively, and smoking among type I DM patients (p-value = 0.002) and among type II DM patients (p-value = 0.000), respectively. Age and smoking were the potential associated factors for the prevalence of periodontitis among type I and II DM. The study provides evidence about the prevalence of periodontitis among DM patients, creates awareness regarding the factors that potentially contribute to worsening periodontal tissues, and the importance of early diagnosis and prevention to avoid the irreversible destruction of the periodontal tissues.

Oral Microbiota in Children and Adolescents with Type 1 Diabetes Mellitus: Novel Insights into the Pathogenesis of Dental and Periodontal Disease

The oral microbiota can be influenced by multiple factors, but only a few studies have focused on the role of glycemic control in determining early alterations of oral microbiota and their association with pathogenesis of both periodontitis and caries. The aim of this study is to evaluate the interplay between bacteria composition, oral hygiene, and glycemic control in a cohort of children with T1D. A total of 89 T1D children were enrolled (62% males, mean age: 12.6 ± 2.2 years). Physical and clinical characteristics, glucometabolic parameters, insulin treatment, and oral hygiene habits data were collected. Microbiological analysis was performed from saliva samples. A high prevalence of cariogenic and periodontopathogens bacteria in our cohort was detected. In particular, in all subjects Actinomyces spp., Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Lactobacillus spp. were isolated. S. mutans was found in about half of the analyzed sample (49.4%), in particular in patients with imbalance values of glycemic control. Moreover, a higher presence of both S. mutans and Veillonella spp. was detected in subjects with poorer glycemic control, in terms of HbA1c, %TIR and %TAR, even adjusting for age, sex, and hygiene habits as covariates. Virtuous oral hygiene habits, such as frequency of toothbrush changes and professional oral hygiene, negatively correlated with the simultaneous presence of Tannerella forsythia, Treponema denticola, and Porphyromonas gingivalis, red complex bacteria. Our study shows it is crucial to pay attention to glycemic control and regular oral hygiene to prevent the establishment of an oral microbiota predisposing to dental and periodontal pathology in subjects with T1D since childhood.

Apelin Enhances the Effects of Fusobacterium nucleatum on Periodontal Ligament Cells In Vitro

This study aimed to explore effects of Fusobacterium nucleatum with or without apelin on periodontal ligament (PDL) cells to better understand pathomechanistic links between periodontitis and obesity. First, the actions of F. nucleatum on COX2, CCL2, and MMP1 expressions were assessed. Subsequently, PDL cells were incubated with F. nucleatum in the presence and absence of apelin to study the modulatory effects of this adipokine on molecules related to inflammation and hard and soft tissue turnover. Regulation of apelin and its receptor (APJ) by F. nucleatum was also studied. F. nucleatum resulted in elevated COX2, CCL2, and MMP1 expressions in a dose- and time-dependent manner. Combination of F. nucleatum and apelin led to the highest (p < 0.05) expression levels of COX2, CCL2, CXCL8, TNF-α, and MMP1 at 48 h. The effects of F. nucleatum and/or apelin on CCL2 and MMP1 were MEK1/2- and partially NF-κB-dependent. The combined effects of F. nucleatum and apelin on CCL2 and MMP1 were also observed at protein level. Moreover, F. nucleatum downregulated (p < 0.05) the apelin and APJ expressions. In conclusion, obesity could contribute to periodontitis through apelin. The local production of apelin/APJ in PDL cells also suggests a role of these molecules in the pathogenesis of periodontitis.

Mitochondrial and Redox Changes in Periodontitis and Type 2 Diabetes Human Blood Mononuclear Cells

Periodontitis (PDT) and type 2 diabetes (T2D) have demonstrated a bidirectional relationship and imbalanced oxidative stress linked to mitochondrial dysfunction. Therefore, we investigated mitochondrial and redox (de)regulation in peripheral blood mononuclear cells (PBMCs) in comorbid T2D-PDT, compared to PDT, T2D patients, and control individuals. PBMCs were analyzed for mitochondrial respiration, reactive oxygen species, antioxidant proteins, and expression of Nrf2-target genes. PDT and T2D-PDT patients exhibited altered periodontal clinical markers, while T2D and T2D-PDT patients displayed increased blood HbA1c. Decreased oxygen consumption and ATP production were observed in the PDT patient's PBMCs. PDT and T2D-PDT PBMCs also evidenced increased H₂O₂ levels and reduced catalase levels (also detected in T2D patients), whereas a compromised glutathione cycle was observed in T2D-PDT patients. PBMCs from both T2D or T2D-PDT patients showed increased Nrf2 protein levels, enhanced GCL activity and GCL-catalytic subunit protein levels, and maintained GCLc, GST, and HO-1 mRNA levels. In contrast, the expressions of Nrf2-target genes were significantly diminished in the PDT patient's PBMCs. Decreased SOD1 and GST mRNA levels were also observed in CD3+CD8+-lymphocytes derived from PDT and T2D-PDT patients. In conclusion, PBMCs from T2D-PDT patients showed major redox changes, while mononuclear cells from PDT patients showed mitochondrial deregulation and reduced expression of Nrf2-target genes.

Novel Herbal Therapeutic YH23537 Improves Clinical Parameters in Ligature-Induced Periodontal Disease Model in Beagle Dogs

Currently, available medicine does not satisfy the clinical unmet needs of periodontal disease. Therefore, novel drugs with improved efficacy profiles are needed. We previously demonstrated that YH14642, water extracts of Notoginseng Radix and Rehmanniae Radix Preparata, improved probing depths in double-blind phase II clinical trial. However, it still has hurdles for commercialization due to the low efficiency of active compound extraction. To resolve this issue, we developed YH23537 through process optimization to extract active compounds efficiently while still achieving the chemical profile of YH14642. In this study, we investigated the therapeutic effects of YH23537 compared with YH14642 using a canine model of ligature-induced periodontitis. Human gingival fibroblast (hGF) cells were treated with various concentrations of YH23537 or YH14642 with lipopolysaccharide (LPS) for 24 hr. IL-6 and IL-8 levels in the conditioned media were determined using Luminex. Sixteen 3-year-old male beagle dogs had their teeth scaled and polished using a piezo-type ultrasonic scaler under general anesthesia and brushed once daily for the following 2 weeks. Two weeks after the scaling procedure, the left upper second premolar (PM2), third premolar (PM3), and fourth premolar (PM4) as well as the left lower PM3, PM4, and first molar (M1) were ligated with silk-wire twisted ligatures. The dogs were fed with soft moistened food to induce periodontitis for 8 weeks, and the ligatures were then removed. YH23537 and YH14642 were administered for 4 weeks, and clinical periodontal parameters such as plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BoP) were determined before and 1, 2, 3, and 4 weeks after treatment. YH23537 inhibited IL-6 and IL-8 secretion in a dose-dependent manner in hGF cells stimulated with LPS. The IC₅₀ values for YH23537 were 43 and 54 μg/ml for IL-6 and IL-8, respectively, while the values for YH14642 were 104 and 117 μg/ml, respectively. In the animal study, clinical parameters including GI, PD, CAL, and BoP were significantly increased after 8 weeks of ligature-induced periodontitis. The YH23537 300 and YH23537 900 mg groups had significant improvements in CAL from 1 to 4 weeks after treatment in comparison to the placebo group. GR values in the YH23537 900 mg group were decreased throughout the treatment period. GI values were also reduced significantly after 4-week treatment with 300 and 900 mg of YH23537. YH23537 at 300 mg doses showed comparable efficacy for CAL and GR with 1,000 mg of YH14642. YH23537 showed therapeutic efficacy against periodontitis in dogs, mediated by anti-inflammatory effects. These findings indicate that YH23537 has the potential for further development as a new drug for patients suffering from periodontal disease.

[Advances in Research on the Mechanism of Association Between Periodontitis and Diabetes Mellitus]

Periodontitis and diabetes mellitus are both chronic diseases with a rather high prevalence and they are closely associated with each other. On one hand, diabetes mellitus poses as a risk factor for periodontitis. On the other hand, periodontitis has a negative impact on glucose control in diabetic patients. The two-way relationship has aroused a lot of research interest in recent years. Herein, approaching the issue by looking at the effect of periodontitis on diabetes, we summarized the mechanism of the traditional periodontal pocket-blood circulation pathway and reviewed the role of the oral-gut axis in the mechanism, which has been proposed in recent years. In addition, regarding the impact of diabetes on periodontitis, we summarized new findings concerning changes in oral microbiota, abnormal levels of cytokines and adipokines, oxidative stress, unbalanced osteogenic and osteoclastic activities, and the accumulation of advanced glycation end-products. We hope this paper will be helpful for further studies on the mechanism of association between periodontitis and diabetes.