Inflammatory mediator response as a potential risk marker for periodontal diseases in insulin-dependent diabetes mellitus patients

Longitudinal analysis of microcirculatory parameters in gingival tissues after tooth extraction in patients with different risk profiles for wound healing disorders - a pilot study

OBJECTIVES

We aimed to establish a risk profile for intraoral wound healing disorders based on measurements of microcirculation in gingival tissues.

MATERIALS AND METHODS

Oxygen saturation (SO2) and blood flow in gingival tissues were measured with tissue spectrometry and laser doppler spectroscopy in 37 patients before/after tooth extractions. Patients were assigned to four groups: anamnestically and periodontally healthy patients (n = 7), anamnestically healthy but suffering from periodontitis (n = 10), anamnestically healthy but smoking and suffering from periodontitis (n = 10) and suffering from diabetes and periodontitis (n = 10). Measurements were performed at three different time points: Baseline measurement (T0), one day post extractionem (p.e.) (T1) and seven days p.e. (T2).

RESULTS

Baseline SO2 values were higher in control patients (p = .038). This effect was most evident in comparison to smokers suffering from periodontitis (p = .042), followed by diabetics suffering from periodontitis (p = .09). An opposite trend was seen for blood flow. Patients suffering from periodontitis demonstrated higher blood flow values (p = .012). Five patients, which belonged to the group of smokers suffering from periodontitis, showed clinically a delayed wound healing.

CONCLUSION

Differences in SO2 and blood flow of gingival tissue could be detected in different groups of patients with existing periodontitis compared to control patients.

CLINICAL RELEVANCE

Lower baseline SO2 values could be a warning signal for possible wound healing disorders after oral surgery.

Periodontitis promotes the progression of diabetes mellitus by enhancing autophagy

Objective

This study aims to identify the periodontitis factor that activates excessive autophagy in pancreatic β cells, resulting in organic lesions of pancreatic islet tissues and diminished insulin secretion, thereby accelerating the progression of diabetes mellitus (DM).

Methods

Sprague-Dawley (SD) rats were induced with periodontitis (PD), type 2 diabetes mellitus (T2DM), or the combination of T2DM and PD (DP) through a high-sugar/high-fat diet and ligation of the tooth neck with silk thread. Alveolar bone resorption was assessed using Micro-CT, blood glucose levels were measured with a blood glucose meter, pancreatic tissue pathology was examined through HE staining, and the expression of autophagy-related proteins Beclin1 and LC3II/LC3I was analyzed using Western blotting.

Results

Micro-CT results revealed more pronounced alveolar bone resorption and root bifurcation exposure in the PD and DP groups compared to the control group, with the DP group exhibiting the most severe condition. HE staining demonstrated the formation of periodontal pockets, severe alveolar bone destruction, and abnormal pancreatic islet tissue morphology in the PD and DP groups. The serum levels of IL-6, TNF-α, and IL-1β increased sequentially in the control, DM, PD, and DP groups (P < 0.05). Relative expressions of GCK and GLUT-2 mRNA decreased in the PD group compared to the control group (P > 0.05), while the mRNA expressions in the DP and DM groups increased (P < 0.05), with the DP group exhibiting higher levels than the DM group (P < 0.05). Western blot results indicated increased expression levels of autophagy proteins Beclin1 and LC3II/LC3I in the DM and DP groups compared to the control group (P < 0.05), with the DP group exhibiting higher levels than the DM group (P < 0.05).

Conclusion

The findings demonstrate that periodontal inflammatory factors may promote the enhancement of pancreatic cell autophagy in diabetic rats.

The utility of salivary CRP and IL-6 as a non-invasive measurement evaluated in patients with COVID-19 with and without diabetes

Background

The available evidence suggests that inflammatory responses, in both systemic and oral tissue, contribute to the pathology of COVID-19 disease. Hence, studies of inflammation biomarkers in oral fluids, such as saliva, might be useful to better specify COVID-19 features.

Methods

In the current study, we performed quantitative real-time PCR to measure salivary levels of C-reactive protein (CRP) and interleukin-6 (IL-6) in saliva obtained from patients diagnosed with mild COVID-19, in a diabetic group (DG; n = 10) and a non-diabetic group (NDG; n = 13). All participants were diagnosed with periodontitis, while six participants with periodontitis but not diagnosed with COVID-19 were included as controls.

Results

We found increases in salivary total protein levels in both the DG and NDG compared to control patients. In both groups, salivary CRP and IL-6 levels were comparable. Additionally, the levels of salivary CRP were significantly correlated with total proteins, in which a strong and moderate positive correlation was found between DG and NDG, respectively. A linear positive correlation was also noted in the relationship between salivary IL-6 level and total proteins, but the correlation was not significant. Interestingly, the association between salivary CRP and IL-6 levels was positive. However, a moderately significant correlation was only found in COVID-19 patients with diabetes, through which the association was validated by a receiver operating curve.

Conclusions

These finding suggest that salivary CRP and IL-6 are particularly relevant as potential non-invasive biomarker for predicting diabetes risk in mild cases of COVID-19 accompanied with periodontitis.

Association of Periodontitis and Atopic Dermatitis with the Levels of IL-13, IL-31, and TSLP in the Gingival Crevicular Fluid

Emerging epidemiological evidence links atopic dermatitis (AD) and periodontitis, although the mechanisms remain unclear. Th2-derived cytokines are key in the development of both diseases, and different gingival crevicular fluid (GCF) profiles among healthy and diseased subjects have been previously reported. This case-control study examined the GCF levels of interleukins (IL)-13, IL-31, and thymic stromal lymphopoietin (TSLP) in 29 subjects with moderate-to-severe AD and 33 controls. All subjects underwent comprehensive clinical and oral evaluations, followed by GCF collection. GCF levels of IL-13, IL-31, and TSLP were assessed using a multiplex-bead immunoassay. Demographic and periodontal parameters were similar among groups (p > 0.05). The GCF levels of IL-31 and TSLP were higher in AD subjects compared to controls (p < 0.05), whereas no significant differences in the GCF levels of IL-13 were noticed (p = 0.377). Moderate-to-severe AD was positively associated with the GCF levels of IL-31 and TSLP, whereas severe periodontitis was negatively associated with IL-31 (p < 0.05). The GCF levels of IL-13 showed no significant associations with either condition (p = 0.689). There was no significant interaction between AD and periodontitis for IL-31 (p < 0.869). These results suggest that AD and periodontitis independently influence the GCF levels of IL-31 in opposing ways, whereas AD alone influences the levels of TSLP.

Hyperglycemia Aggravates Periodontitis via Autophagy Impairment and ROS-Inflammasome-Mediated Macrophage Pyroptosis

Macrophage pyroptosis drives the secretion of IL-1β, which has been recently reported to be a featured salivary biomarker for discriminating periodontitis in the presence of diabetes. This study aimed to explore whether macrophage pyroptosis plays a role in the development of diabetes mellitus–periodontitis, as well as potential therapeutic strategies. By establishing a model of experimental diabetes mellitus–periodontitis in rats, we found that IL-1β and gasdermin D were highly expressed, leading to aggravated destruction of periodontal tissue. MCC950, a potent and selective molecule inhibitor of the NLRP3 inflammasome, effectively inhibited macrophage pyroptosis and attenuated alveolar bone losses in diabetes mellitus–periodontitis. Consistently, in vitro, high glucose could induce macrophage pyroptosis and thus promoted IL-1β production in macrophages stimulated by lipopolysaccharide. In addition, autophagy blockade by high glucose via the mTOR-ULK1 pathway led to severe oxidative stress response in macrophages stimulated by lipopolysaccharide. Activation of autophagy by rapamycin, clearance of mitochondrial ROS by mitoTEMPO, and inhibition of inflammasome by MCC950 could significantly reduce macrophage pyroptosis and IL-1β secretion. Our study demonstrates that hyperglycemia promotes IL-1β production and pyroptosis in macrophages suffered by periodontal microbial stimuli. Modulation of autophagy activity and specific targeting of the ROS-inflammasome pathway may offer promising therapeutic strategies to alleviate diabetes mellitus–periodontitis.

Impact of Intermittent Fasting on Metabolic Syndrome and Periodontal Disease-A Suggested Preventive Strategy to Reduce the Public Health Burden

Metabolic syndrome (MetS) prevalence continues to climb significantly worldwide in today's ad libitum society. MetS has tremendous societal and economic ramifications, making it imperative to develop effective strategies for preventing and controlling it to alleviate this growing burden. Periodontal disease and MetS are associated with several risk factors. Studies in the past have demonstrated that obesity, cardiovascular illness, and type 2 diabetes mellitus have a negative effect on the severity of the periodontal disease. Patients with metabolic syndrome have elevated serum levels of proinflammatory mediators such as tumor necrosis factor-alpha interleukin-6 and C-reactive protein. Similar inflammatory mediators, such as interleukin-6, tumor necrosis factor-alpha, and C-reactive protein, are increased in patients with severe periodontal disease. Remarkably, intermittent fasting is underpinned by scientific evidence, claiming to be the most effective non-pharmacological, potential therapeutic alternative for combating a wide range of metabolic, inflammatory, and lifestyle-related diseases. Nonetheless, an insufficient investigation has been performed to determine whether intermittent fasting has therapeutic benefits on periodontal inflammation and diseases. Here, we show the interrelationship between metabolic syndrome and periodontal disease and contextualize the beneficial impact of intermittent fasting in modulating the chronic metabolic and periodontal inflammatory response. We also anticipate that this review paves the way for further exploration of intermittent fasting as a unique research paradigm representing a cost-effective alternative strategy to conventional disease management in patients with periodontal diseases and metabolic syndrome which may serve as the foundation for an integrative vision relevant to primary, diagnostic, and therapeutic purposes.

Identification of cross-talk pathways and ferroptosis-related genes in periodontitis and type 2 diabetes mellitus by bioinformatics analysis and experimental validation

Purpose

There is a bidirectional relationship between periodontitis and type 2 diabetes mellitus (T2DM). The aim of this study was to further explore the pathogenesis of this comorbidity, screen out ferroptosis-related genes involved in the pathological process, and predict potential drug targets to develop new therapeutic strategies.

Methods

Common cross-talk genes were identified from periodontitis datasets (GSE16134, GSE10334 and GSE106090) and T2DM databases (DisGeNET and GeneCard). Then, GO and KEGG enrichment analyses, PPI network analysis and hub gene identification were performed. The association between ferroptosis and periodontitis with T2DM was investigated by Pearson correlation analysis. Core ferroptosis-related cross-talk genes were identified and verified by qRT-PCR. Potential drugs targeting these core genes were predicted via DGIDB.

Results

In total, 67 cross-talk genes and two main signalling pathways (immuno-inflammatory pathway and AGE-RAGE signalling pathway) were identified. Pearson correlation analysis indicated that ferroptosis served as a crucial target in the pathological mechanism and treatment of periodontitis with T2DM. IL-1β, IL-6, NFE2L2 and ALOX5 were identified as core ferroptosis-related genes and the qRT-PCR detection results were statistically different. In total, 13 potential drugs were screened out, among which, Echinacea and Ibudilast should be developed first.

Conclusions

This study contributes to a deeper understanding of the common pathogenesis of periodontitis and T2DM and provides new insights into the role of ferroptosis in this comorbidity. In addition, two drugs with potential clinical application value were identified. The potential utility of these drugs requires further experimental investigation.

Comparison of the triglyceride glucose (TyG) index, triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, and metabolic score for insulin resistance (METS-IR) associated with periodontitis in Korean adults

Background:

Periodontitis is one of the most common diseases associated with the oral cavity. Previous studies have suggested that there is an association between periodontitis and metabolic dysfunction. Recently, the triglyceride glucose (TyG) index, high-density lipoprotein cholesterol (TG/HDL-C) ratio, and metabolic score for insulin resistance (METS-IR) index have been identified as useful markers for assessing insulin resistance.

Objective:

This study aimed to evaluate the relationship between periodontitis and non-insulin-based insulin resistance (IR) indices and compare the predictive values of these indices in the Korean population.

Design:

This is a cross-sectional study.

Methods:

A total of 13,584 participants were included in the 2013–2015 Korean National Health and Nutrition Examination Survey data. A community periodontal index score⩾3 was used to define periodontitis. Participants were divided into quartiles according to each index. Odds ratios (ORs) and 95% confidence intervals (CIs) for the prevalence of periodontitis and the TyG index, TG/HDL-C ratio, and METS-IR index quartiles were calculated using multiple logistic regression analysis. We estimated the areas under the receiver operating characteristic curves (AUCs) of the indices to compare the predictive values of the three indices.

Results:

Compared with quartile 1, the fourth quartile ORs (95% CIs) for periodontitis were 1.23 (1.01–1.49) for the TyG index, 1.23 (1.02–1.48) for the TG/HDL-C ratio, and 1.53 (1.25–1.88) for the METS-IR index after adjustment for confounders. The AUC (95% CIs) was 0.608 (0.598–0.618) for the TyG index, 0.600 (0.590–0.610) for the TG/HDL-C ratio, and 0.617 (0.608–0.627) for the METS-IR index to identify periodontitis. The predictive power of METS-IR was significantly higher than that of the TyG index and TG/HDL-C.

Conclusion:

Higher TG/HDL-C ratio, TyG, and METS-IR indices are associated with a higher prevalence of periodontitis. The METS-IR index is a more powerful predictor of periodontitis prevalence than the TyG index and TG/HDL-C ratio.

Periodontitis, age-related diseases and diabetes in an endocrinological outpatient setting (PARADIES): a cross-sectional analysis on predictive factors for periodontitis in a German outpatient facility

BACKGROUND

Diabetes mellitus (DM) is a risk factor for periodontitis. Data on risk-modifying factors for periodontitis in diabetes patients are limited.

AIMS

We tested whether sex, age, type of diabetes, metabolic state, comorbidities, complications, measures of well-being and quality of life are predicting periodontitis in a German diabetes outpatient cohort.

METHODS

In total, 1180 out of 1293 participating DM patients completed questionnaires on quality of life, dental hygiene and health. All patients also filled out a modified version of the periodontitis risk questionnaire by the American Association for Periodontology, from which the status of "assumed periodontitis" was deducted. In a subset of participants (n = 461), we measured or inquired the most recent Community Parodontal Index (CPI), providing an objective measure for clinically diagnosed periodontitis. For all subjects, DM history and phenotype, major metabolic parameters (HbA1c, BMI, LDL and total cholesterol levels), general health risk factors, comorbidities and medication were collected.

RESULTS

Clinically diagnosed (CPI > 2) and assumed periodontitis was detected in 60-67% of our patients. Male sex and oral health-related quality of life were associated with clinically diagnosed periodontitis. Male sex, age, smoking, dental hygiene, dental control and diabetes-related quality of life independently predicted assumed periodontitis.

CONCLUSION

In DM patients, quality of life and lifestyle factors which systemically alter microvascular and immunological functions seem to predict periodontitis. Further studies are needed for replication and for pathomechanistic clarification.

Biomarkers in Oral Fluids as Diagnostic Tool for Psoriasis

Psoriasis is a prevalent worldwide chronic immuno-inflammatory skin disease with various variants and atypical cases. The use of biomarkers for the diagnosis of psoriasis can favor timely treatment and thus improve the quality of life of those affected. In general, the search for biomarkers in oral fluids is recommended as it is a non-invasive and fast technique. This narrative review aimed to identify biomarkers in gingival crevicular fluid (GCF) and saliva to diagnose psoriasis. To achieve this goal, we selected the available literature using the following MESH terms: “psoriasis”, “saliva” and “gingival crevicular fluid”. The studies analyzed for this review cover original research articles available in English. We found three full articles available for psoriasis biomarkers in GCF and ten articles available for psoriasis biomarkers in saliva. Studies showed that in the saliva of healthy individuals and those with psoriasis, there were differences in the levels of inflammatory cytokines, immunoglobulin A, and antioxidant biomarkers. In GCF, individuals with psoriasis showed higher levels of S100A8, IL-18 and sE-selectin in comparison to healthy individuals, independent of periodontal status. Despite these findings, more studies are required to determine an adequate panel of biomarkers to use in saliva or GCF for psoriasis.

Subgingival microbiome in periodontitis and type 2 diabetes mellitus: an exploratory study using metagenomic sequencing

Purpose

To explore differences in the subgingival microbiome according to the presence of periodontitis and/or type 2 diabetes mellitus (T2D), a metagenomic sequencing analysis of the subgingival microbiome was performed.

Methods

Twelve participants were divided into 4 groups based on their health conditions (periodontitis, T2D, T2D complicated with periodontitis, and generally healthy). Subgingival plaque was collected for metagenomic sequencing, and gingival crevicular fluids were collected to analyze the concentrations of short-chain fatty acids.

Results

The shifts in the subgingival flora from the healthy to periodontitis states were less prominent in T2D subjects than in subjects without T2D. The pentose and glucuronate interconversion, fructose and mannose metabolism, and galactose metabolism pathways were enriched in the periodontitis state, while the phosphotransferase system, lipopolysaccharide (LPS) and peptidoglycan biosynthesis, bacterial secretion system, sulfur metabolism, and glycolysis pathways were enriched in the T2D state. Multiple genes whose expression was upregulated from the red and orange complex bacterial genomes were associated with bacterial biofilm formation and pathogenicity. The concentrations of propionic acid and butyric acid were significantly higher in subjects with periodontitis, with or without T2D, than in healthy subjects.

Conclusions

T2D patients are more susceptible to the presence of periodontal pathogens and have a higher risk of developing periodontitis. The pentose and glucuronate interconversion, fructose and mannose metabolism, galactose metabolism, and glycolysis pathways may represent the potential microbial functional association between periodontitis and T2D, and butyric acid may play an important role in the interaction between these 2 diseases. The enrichment of the LPS and peptidoglycan biosynthesis, bacterial secretion system, and sulfur metabolism pathways may cause T2D patients to be more susceptible to periodontitis.

Neutrophils and their role in the aetiopathogenesis of type 1 and type 2 diabetes

Multiple and complex aetiological processes underlie diabetes mellitus, which invariably result in the development of hyperglycaemia. Although there are two prevalent distinct forms of the disease, that is, type 1 and type 2 diabetes, accumulating evidence indicates that these syndromes share more aetiopathological mechanisms than originally thought. This compels a rethinking of the approaches to prevent and treat the different manifestations of what eventually becomes a hyperglycaemic state. This review aims to address the involvement of neutrophils, the most abundant type of granulocytes involved in the initiation of the acute phase of inflammation, in the aetiopathogenesis of diabetes mellitus, with a focus on type 1 and type 2 diabetes. We review the evidence that neutrophils are the first leucocytes to react to and accumulate inside target tissues of diabetes, such as the pancreas and insulin-sensitive tissues. We then review available data on the role of neutrophils and their functional alteration, with a focus on NETosis, in the progression towards clinical disease. Finally, we review potential approaches as secondary and adjunctive treatments to limit neutrophil-mediated damage in the prevention of the progression of subclinical disease to clinical hyperglycaemia.

Anti-Inflammatory and Antioxidant Properties of Carvacrol and Magnolol, in Periodontal Disease and Diabetes Mellitus

Periodontal disease and diabetes mellitus are two pathologies that are extremely widespread worldwide and share the feature of chronic inflammation. Carvacrol is a phenolic monoterpenoid, produced by a variety of herbs, the most well-known of which is Origanum vulgare. Magnolol is a traditional polyphenolic compound isolated from the stem bark of Magnolia officinalis, mainly used in Chinese medicine. The purpose of this paper is to review the therapeutic properties of these bioactive compounds, in the treatment of periodontitis and diabetes. Based on our search strategy we conducted a literature search in the PubMed and Google Scholar databases to identify studies. A total of one hundred eighty-four papers were included in the current review. The results show that carvacrol and magnolol have anti-inflammatory, antioxidant, antimicrobial, anti-osteoclastic, and anti-diabetic properties that benefit both pathologies. Knowledge of the multiple activities of carvacrol and magnolol can assist with the development of new treatment strategies, and the design of clinical animal and human trials will maximize the potential benefits of these extracts in subjects suffering from periodontitis or diabetes.

Effect of Conventional Periodontal Treatment (Scaling and Root Planing) on Type-2 Diabetic Patient with Moderate Generalized Chronic Periodontitis: A Clinical Study

Background:

The aim is to assess the effect of periodontal therapy and scaling and root planing (SRP) on the metabolic control in Type 2 diabetes mellitus (DM) patients with chronic periodontitis based on the estimation of glycated hemoglobin (HbA1c).

Materials and Methods:

A prospective, comparative, clinical study was performed on 50 patients suffering from Type 2 DM with moderate, generalized chronic periodontitis. Type 2 moderately controlled diabetic patients with HbA1c values within the range of 6%–8% were selected. The parameters recorded were gingival index, plaque index, sulcus bleeding index, probing pocket depth, clinical attachment level, and HbA1c. The recordings were done at baseline and 6 months after SRP procedures.

Results:

Reductions in all the clinical parameters were observed and were found to be statistically significant (P < 0.05).

Conclusion:

SRP resulted in a statistically significant reduction in the clinical parameters and HbA1c. Hence, periodontal treatment should be included in the management of diabetic patients.

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

Periodontal disease has been reported to be associated with diabetes mellitus. However, the direction of the association and the influence of bias are not clear. Thus, the aim of this systematic review and meta-analysis was to summarize the existing evidence on the bidirectional prospective association between periodontal disease and diabetes mellitus by accounting for the risk of bias of the original studies. The literature search was conducted on the electronic data sources PubMed and Web of Science up to February 9th, 2021. We included observational studies, which investigated the prospective association between diabetes mellitus and periodontal disease or vice versa. The risk of bias of the primary studies was evaluated by applying the Quality in Prognosis Studies (QUIPS) tool. Random effects models were used to calculate summary relative risk (SRR) with 95% CI. Subgroup analyses were applied to investigate heterogeneity and the robustness of the finding. In total, 15 studies were included . The SRR for incident diabetes mellitus was 1.26 (95% CI 1.12, 1.41; I²: 71%, n = 10; participants = 427,620; identified cases = 114,361), when comparing individuals with periodontitis to individuals without periodontitis. The SRR for incident periodontitis was 1.24 (95% CI 1.13, 1.37; I²: 92%, n = 7; participants = 295,804; identified cases: > 22,500), comparing individuals with diabetes to individuals without diabetes. There were no significant differences between subgroups after stratification for risk of bias. The findings show a positive bidirectional association between periodontal disease and diabetes mellitus, and thus, underline the need for screening of patients with periodontitis regarding diabetes mellitus and vice versa. The main limitation of the study is the high unexplained heterogeneity between the studies including the different assessment methods of the disease diagnosis.

Hyperglycemia modulates M1/M2 macrophage polarization via reactive oxygen species overproduction in ligature-induced periodontitis

BACKGROUND AND OBJECTIVE

Periodontitis in diabetic patients is characterized by enhanced inflammation and aggravated tissue damage in comparison with that in non-diabetic counterparts. The progression of periodontal damage under diabetic condition can be partly ascribed to hyperglycemia-induced disturbance between immune activation and inflammation resolution, where macrophages are capable of participating given their plasticity in response to different stimuli. Herein, we aimed to investigate the changes of macrophage polarization in periodontitis under diabetic condition and the underlying mechanism.

MATERIALS AND METHODS

Type-1 diabetes was induced by the injection of streptozotocin (STZ, 60 mg/kg) in Sprague-Dawley rats. Rats in N-acetyl cysteine (NAC)-treated groups received NAC dissolved in drinking water (200 mg/kg/day). Experimental periodontitis was induced by ligating 3-0 silk around left maxillary second molars for 4 weeks. Alveolar bone destruction was tested by micro-computed tomography and tartrate-resistant acid phosphatase (TRAP) staining. M1/M2 macrophage polarization in periodontal tissue was detected by immunohistochemistry staining. RAW264.7 were cultured in normal glucose (5.5 mM) or high glucose environment (25 mM) with or without NAC (8 mmol/L). LPS (100 ng/ml) and IL-4 (20 ng/ml) were used to induce M1 macrophages and M2 macrophages, respectively. M1/M2 macrophage polarization was detected by qRT-PCR, immunofluorescent staining, and flow cytometry. Reactive oxygen species (ROS) accumulation was detected by fluorogenic probes. RANKL (100 ng/ml) were applied to induce osteoclastogenic differentiation of RAW264.7, and osteoclast formation was examined by TRAP staining.

RESULTS

Rats with diabetes displayed enhanced macrophages infiltration and M1 macrophage polarization in periodontal lesions compared with vehicle-treated rats. Under LPS or IL-4 stimulation, high glucose culture of RAW264.7 elevated ROS level and increased the expression of M1 macrophage markers (iNOS, TNF-α, and IL-6) whereas decreased the expression of M2 macrophage markers (Arg-1 and CD206). Supernatants of high glucose-treated M1/M2 macrophages enhanced osteoclast formation compared to normal glucose-cultured cells. Decreasing ROS level via NAC partially reversed the effect of high glucose on M1/M2 macrophage polarization. Meanwhile, daily intake of NAC in rodent models inhibited M1 macrophage polarization, which subsequently ameliorated alveolar bone loss and decreased osteoclast numbers in periodontitis in diabetic rats.

CONCLUSION

These findings demonstrated that hyperglycemia could polarize macrophage toward M1 macrophages via overproducing ROS under inflammatory condition, which might take responsibility for aggravated periodontal damage in periodontitis under diabetic condition. Inhibiting M1 macrophages and restoring M2 macrophages by ROS scavenger is hopefully a potential adjunct treatment strategy for diabetic periodontitis.

Resilience of the oral microbiome

The human mouth harbors a complex microbiota, the composition of which is potentially influenced by a wide range of factors, including the intake of food and drink, the availability of endogenous nutrients, the host immune system, drug treatments, and systemic diseases. Despite these possible influences, the oral microbiota is remarkably resilient, particularly in comparison with the microbiota of the large intestine. Diet, with the exception of excessive and/or frequent consumption of fermentable carbohydrate or supplementation with nitrate, has minimal impact on the composition of the oral bacterial community. The common oral diseases dental caries and the periodontal diseases is associated with modification of the oral microbiota primarily as a result of the ecological changes induced by excessive acid production and inflammation, respectively. Systemically-administered antimicrobials have only a small effect on the composition of the oral bacterial community, and while locally delivered antimicrobials can have some clinical benefits, the biofilm lifestyle of oral bacteria lends them substantial resistance to the agents used. Saliva plays an important role in oral microbial ecology, by supplying nutrients and providing protection against colonization by nonoral organisms. Dry mouth is one condition that has a major effect on the microbiota, resulting in increased colonization by opportunistic pathogens. Some systemic diseases do affect the oral microbiome, notably diabetes, in which raised levels of glucose in saliva and tissue impact on bacterial nutrition.

Association between retinopathy, nephropathy, and periodontitis in type 2 diabetic patients: a Meta-analysis

AIM

To verify the association between retinopathy, nephropathy, and periodontitis in type 2 diabetic (T2D) patients.

METHODS

Several electronic databases were available for our comprehensive search including China National Knowledge Infrastructure (CNKI), Chinese VIP Information (VIP), Wanfang, Web of Science, ScienceDirect and PubMed and were queried for relevant citations (updated to Mar. 2019). RevMan was utilized to perform Meta analysis and publication bias detection. After evaluation of the methodological quality of included studies, a fixed or random effect model was utilized to analyze data from included studies.

RESULTS

A total of eight articles were finally included in this Meta analysis. In all 3987 subjects, there were 1207 T2D patients accompanying with microvascular complications and 1734 patients with periodontitis as well. The Meta forest plot presented little heterogeneity of the eight studies (P<0.00001, I ²=89%). The total effect demonstrated periodontitis was associated with overall microvascular complications (OR: 1.96, 95%CI: 1.67-2.30, Z=8.25, P<0.00001). Subgroup investigations among the studies in Asian (OR: 2.33, 95%CI: 1.91-2.85) and North American (OR: 1.42, 95%CI: 1.08-1.86) populations confirmed the existed association between retinopathy, nephropathy, and periodontitis. While the strength of such associations between periodontitis and diabetic microvascular complications were more obvious in the Asians than North Americans. All the results indicated that periodontitis was associated with diabetic retinopathy (OR: 3.77, 95%CI: 2.71-5.24), diabetic nephropathy (OR: 1.55, 95%CI: 1.24-1.94) in T2D patients.

CONCLUSION

The periodontitis is associated with diabetic retinopathy, diabetic nephropathy among T2D patients and further large sample size clinical trials are in need to confirm the findings.

Periodontal Health and Systemic Conditions

According to the new classification proposed by the recent 2017 World Workshop on Periodontal and Peri-implant Diseases and Conditions, periodontitis, necrotizing periodontal diseases, periodontitis as a manifestation of systemic diseases, and systemic diseases or conditions affecting the periodontal supporting tissues, are considered as separate entities. Scientific evidence has demonstrated that periodontal diseases are not just simple bacterial infections but rather complex diseases of multifactorial complexity that interplay with the subgingival microbes, the host immune, and inflammatory responses. Despite dental plaque biofilm being considered the primary risk factor for periodontitis in the vast majority of patients that dentists encounter on a daily basis, there are other factors that can also contribute and/or accelerate pathologic progressive attachment loss. In this article, the authors aim to briefly review and discuss the present evidence regarding the association between periodontal diseases and systemic diseases and conditions.

The impact of diabetes on periodontal diseases

The susceptibility and severity of periodontal diseases is made more severe by diabetes, with the impact on the disease process inversely proportional to the level of glycemic control. Although type 1 diabetes mellitus and type 2 diabetes mellitus have different etiologies, and their impact on bone is not identical, they share many of the same complications. Studies in animals and humans agree that both forms of diabetes increase inflammatory events in periodontal tissue, impair new bone formation, and increase expression of RANKL in response to bacterial challenge. High levels of glucose, reactive oxygen species, and advanced glycation end-products are found in the periodontium of diabetic individuals and lead to increased activation of nuclear factor-kappa B and expression of inflammatory cytokines such as tumor necrosis factor and interleukin-1. Studies in animals, moreover, suggest that there are multiple cell types in periodontal tissues that are affected by diabetes, including leukocytes, vascular cells, mesenchymal stem cells, periodontal ligament fibroblasts, osteoblasts, and osteocytes. The etiology of periodontal disease involves the host response to bacterial challenge that is affected by diabetes, which increases the expression of RANKL and reduces coupled bone formation. In addition, the inflammatory response also modifies the oral microbiota to render it more pathogenic, as demonstrated by increased inflammation and bone loss in animals where bacteria are transferred from diabetic donors to germ-free hosts compared with transfer from normoglycemic donors. This approach has the advantage of not relying upon limited knowledge of the specific bacterial taxa to determine pathogenicity, and examines the overall impact of the microbiota rather than the presumed pathogenicity of a few bacterial groups. Thus, animal studies have provided new insights into pathogenic mechanisms that identify cause-and-effect relationships that are difficult to perform in human studies.

The effect of periodontal and prosthodontic therapy on glycemic control in patients with diabetes

PURPOSE

To evaluate the effect of periodontal and prosthodontic therapy on glycated hemoglobin A(HbA1c) level in patients with diabetes.

MATERIALS AND METHODS

This is a retrospective study of 70 patients suffering from diabetes who visited the Kyungpook National University Hospital between January 2016 and May 2018. Patients underwent medical evaluation for their routine check-up, which includes laboratory test for HbA1c levels. Among the 70 patients, 35 patients also visited Kyungpook National University Dental Hospital during the same period to receive periodontal and prosthodontic therapy, while the other 35 patients did not receive such therapy. The HbA1c levels were compared before and after periodontal and prosthodontic therapy. Comparisons between groups and within groups were performed using independent t-test.

RESULTS

The HbA1c levels in the group who have received periodontal and prosthodontic therapy decreased from 7.2 to 6.7 (P=.001). The HbA1c levels in the control group decreased from 7.2 to 7.1 (P=.580). The difference in changes between the two patient groups was statistically significant (P=.011).

CONCLUSION

Periodontal and prosthodontic therapy can be effective on glycemic control in patients with diabetes.

Influence of T2DM and prediabetes on blood DC subsets and function in subjects with periodontitis

OBJECTIVE

To compare the myeloid and plasmacytoid DC counts and maturation status among subjects with/without generalized periodontitis (GP) and type 2 diabetes mellitus (T2DM).

METHODS

The frequency and maturation status of myeloid and plasmacytoid blood DCs were analyzed by flow cytometry in four groups of 15 subjects: healthy controls, T2DM with generalized CP (T2DM + GP), prediabetes with GP (PD + GP), and normoglycemics with GP (NG + GP). RT-PCR was used to determine levels of Porphyromonas gingivalis in the oral biofilms and within panDCs. The role of exogenous glucose effects on differentiation and apoptosis of healthy human MoDCs was explored in vitro.

RESULTS

Relative to controls and to NG + GP, T2DM + GP showed significantly lower CD1c + and CD303 + DC counts, while CD141 + DCs were lower in T2DM + GP relative to controls. Blood DC maturation required for mobilization and immune responsiveness was not observed. A statistically significant trend was observed for P. gingivalis levels in the biofilms of groups as follows: controls <NG+GP < PD+GP < T2DM+GP. Moreover, significantly higher P. gingivalis levels were observed in blood DCs of NG + GP than controls, whereas no differences were observed between controls and PD + GP/T2DM + GP. In vitro differentiation of MoDCs was significantly decreased, and apoptosis was increased by physiologically relevant glucose levels.

CONCLUSION

Type 2 diabetes mellitus appears to inhibit important DC immune homeostatic functions, including expansion and bacterial scavenging, which might be mediated by hyperglycemia.

Loss of interleukin-10 exacerbates early Type-1 diabetes-induced bone loss

Type-1 diabetes (T1D) increases systemic inflammation, bone loss, and risk for bone fractures. Levels of the anti-inflammatory cytokine interleukin-10 (IL-10) are decreased in T1D, however their role in T1D-induced osteoporosis is unknown. To address this, diabetes was induced in male IL-10 knockout (KO) and wild-type (WT) mice. Analyses of femur and vertebral trabecular bone volume fraction identified bone loss in T1D-WT mice at 4 and 12 weeks, which in T1D-IL-10-KO mice was further reduced at 4 weeks but not 12 weeks. IL-10 deficiency also increased the negative effects of T1D on cortical bone. Osteoblast marker osterix was decreased, while osteoclast markers were unchanged, suggesting that IL-10 promotes anabolic processes. MC3T3-E1 osteoblasts cultured under high glucose conditions displayed a decrease in osterix which was prevented by addition of IL-10. Taken together, our results suggest that IL-10 is important for promoting osteoblast maturation and reducing bone loss during early stages of T1D.

Evaluating All Potential Oral Complications of Diabetes Mellitus

Diabetes mellitus (DM) is associated with several microvascular and macrovascular complications, such as retinopathy, nephropathy, neuropathy, and cardiovascular diseases. The pathogenesis of these complications is complex, and involves metabolic and hemodynamic disturbances, including hyperglycemia, insulin resistance, dyslipidemia, hypertension, and immune dysfunction. These disturbances initiate several damaging processes, such as increased reactive oxygen species (ROS) production, inflammation, and ischemia. These processes mainly exert their damaging effect on endothelial and nerve cells, hence the susceptibility of densely vascularized and innervated sites, such as the eyes, kidneys, and nerves. Since the oral cavity is also highly vascularized and innervated, oral complications can be expected as well. The relationship between DM and oral diseases has received considerable attention in the past few decades. However, most studies only focus on periodontitis, and still approach DM from the limited perspective of elevated blood glucose levels only. In this review, we will assess other potential oral complications as well, including: dental caries, dry mouth, oral mucosal lesions, oral cancer, taste disturbances, temporomandibular disorders, burning mouth syndrome, apical periodontitis, and peri-implant diseases. Each oral complication will be briefly introduced, followed by an assessment of the literature studying epidemiological associations with DM. We will also elaborate on pathogenic mechanisms that might explain associations between DM and oral complications. To do so, we aim to expand our perspective of DM by not only considering elevated blood glucose levels, but also including literature about the other important pathogenic mechanisms, such as insulin resistance, dyslipidemia, hypertension, and immune dysfunction.

Upregulation of free fatty acid receptors in periodontal tissues of patients with metabolic syndrome and periodontitis

BACKGROUND AND OBJECTIVE

Metabolic syndrome (MetS) exacerbates periodontitis. Since saturated fatty acid (SFA) is increased in MetS and enhances lipopolysaccharide (LPS)-induced proinflammatory cytokine expression in macrophages, it has been considered to play a role in MetS-exacerbated periodontitis. However, it remains unknown how fatty acid receptors, which mediate the interaction of cells with SFA and uptake of SFA, are expressed and regulated in the periodontal tissue. In this study, we tested our hypothesis that the periodontal expression of fatty acid receptors GPR40 and CD36 is increased in patients with both MetS and periodontitis. We also determined the effect of SFA and LPS on GPR40 and CD36 expression in vitro.

MATERIAL AND METHODS

Periodontal tissue specimens were collected from 11 participants without MetS and periodontitis, 12 participants with MetS, 11 participants with periodontitis, and 14 participants with both MetS and periodontitis after surgeries. The tissues were processed, and GPR40 and CD36 were detected by immunohistochemistry. Furthermore, cultured macrophages and gingival fibroblasts were treated with LPS, palmitate, a major SFA, or LPS plus palmitate and the expression of GPR40 and CD36 was then quantified.

RESULTS

Analysis of clinical data showed that age, smoker, gender, and race/ethnicity were not significantly different among 4 groups. Immunohistochemistry showed that GPR40 and CD36 were expressed by epithelial cells, fibroblasts, and immune cells. Quantitative data showed that GPR40 expression is increased in patients with periodontitis, MetS, or both periodontitis and MetS while CD36 expression is increased only in patients with both periodontitis and MetS. The in vitro studies showed that the expression of GPR40 and CD36 in macrophages and fibroblasts was upregulated by the combination of LPS and palmitate.

CONCLUSION

Periodontal expression of GPR40 and CD36 was upregulated in patients with both MetS and periodontitis, and GPR40 and CD36 in macrophages and fibroblasts were upregulated in vitro by the combination of LPS and palmitate, suggesting that GPR40 and CD36 may be involved in MetS-exacerbated periodontitis.

Periodontal, metabolic, and cardiovascular disease: Exploring the role of inflammation and mental health

Previous evidence connects periodontal disease, a modifiable condition affecting a majority of Americans, with metabolic and cardiovascular morbidity and mortality. This review focuses on the likely mediation of these associations by immune activation and their potential interactions with mental illness. Future longitudinal, and ideally interventional studies, should focus on reciprocal interactions and cascading effects, as well as points for effective preventative and therapeutic interventions across diagnostic domains to reduce morbidity, mortality and improve quality of life.

Diabetes Activates Periodontal Ligament Fibroblasts via NF-κB In Vivo

Diabetes mellitus increases periodontitis and pathogenicity of the oral microbiome. To further understand mechanisms through which diabetes affects periodontitis, we examined its impact on periodontal ligament fibroblasts in vivo and in vitro. Periodontitis was induced by inoculation of Porphyromonas gingivalis and Fusobacterium nucleatum in normoglycemic and diabetic mice. Diabetes, induced by multiple low-dose injections of streptozotocin increased osteoclast numbers and recruitment of neutrophils to the periodontal ligament, which could be accounted for by increased CXC motif chemokine 2 (CXCL2) and receptor activator of nuclear factor kappa B ligand (RANKL) expression by these cells. Diabetes also stimulated a significant increase in nuclear factor kappa B (NF-κB) expression and activation in periodontal ligament (PDL) fibroblasts. Surprisingly, we found that PDL fibroblasts express a 2.3-kb regulatory unit of Col1α1 (collagen type 1, alpha 1) promoter typical of osteoblasts. Diabetes-enhanced CXCL2 and RANKL expression in PDL fibroblasts was rescued in transgenic mice with lineage-specific NF-κB inhibition controlled by this regulatory element. In vitro, high glucose increased NF-κB transcriptional activity, NF-κB nuclear localization, and RANKL expression in PDL fibroblasts, which was reduced by NF-κB inhibition. Thus, diabetes induces changes in PDL fibroblast gene expression that can enhance neutrophil recruitment and bone resorption, which may be explained by high glucose-induced NF-κB activation. Furthermore, PDL fibroblasts express a regulatory element in vivo that is typical of committed osteoblasts.

Effects of nonsurgical periodontal treatment on glycated haemoglobin on type 2 diabetes patients (PARODIA 1 study): a randomized controlled trial in a sub-Saharan Africa population

BACKGROUND

There is a burglar association between diabetes and periodontitis. Many studies has shown that periodontitis treatment can help improving glycemic control in diabetes patients but little evidence of non-surgical treatment benefit is available in sub Saharan african diabetes patients. We aimed to assess the effects of non-surgical periodontal treatment (NSPT) of chronic periodontitis on glycaemic control in poorly controlled type 2 diabetes patients (T2D) in a sub-Saharan Africa urban setting.

METHODS

A total of 34 poorly controlled T2D patients with chronic periodontitis aged 51.4 ± 8.8 years (mean ± SD), with known duration of diabetes of 55.5 ± 42.6 months, and HbA1c of 9.3 ± 1.3% were randomly assigned to two groups. The treatment group (Group 1, n = 17) received immediate ultrasonic scaling, scaling and root planning along with subgingival 10% povidone iodine irrigation, whereas the control group (Group 2, n = 17) was assigned to receive delayed periodontal treatment 3 months later. Pharmacological treatment was unchanged and all participants received the same standardized education session on diabetes management and dental hygiene. The primary outcome was the 3-month change in HbA1c from baseline. Plaque index (PI), gingival bleeding index (GBI), pocket depth (PD), clinical attachment loss (CAL) were also assessed prior to, at 6 and 12 weeks after enrolment.

RESULTS

Two subjects in each group were excluded from the study. Data were analyzed on thirty patients (15 per group). Non-surgical periodontal treatment with education for better dental hygiene (group 1) significantly improved all periodontal parameters whereas education only (group 2) improved only the plaque index among all periodontal parameters. Immediate non-surgical periodontal treatment induced a reduction of HbA1c levels by 3.0 ± 2.4 points from 9.7 ± 1.6% at baseline to 6.7 ± 2.0% 3 months after NSPT, (p ˂ 0.001) but the change was not significant in group 2, from mean 8.9 ± 0.9% at baseline vs 8.1 ± 2.6% after 3 months (p = 0.24).

CONCLUSION

Non-surgical periodontal treatment markedly improved glycaemic control with an attributable reduction of 2.2 points of HbA1c in poorly controlled T2D patients in a sub Saharan setting.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02745015 Date of registration: July 17, 2016 'Retrospectively registered'.

Correlations between gingival crevicular blood glucose and capillary blood glucose: A preliminary report

INTRODUCTION

Oral health plays an important role for screening of many systemic diseases. Hence, dentists play an important role in screening for systemic diseases as well. Early diagnosis of any systemic diseases can prevent long-term complications. Diabetic is one of the common chronic diseases. Hence, the study had been undertaken to evaluate whether gingival crevicular blood (GCB) can be used to screen for diabetes during routine oral health checkups.

MATERIALS AND METHODS

This analytical study included thirty participants who visited the Department of Periodontics, who fulfilled inclusion criteria and were willing to participate. Blood samples were collected by finger stick method and periodontal probing. The glucose levels of both the samples were estimated using glucometer and correlated the levels from both the methods.

RESULTS

Correlation between capillary finger stick blood glucose and GCB glucose was high (0.97) and was significant at 0.01 level.

CONCLUSION

Blood oozing during routine periodontal examination can be used for diabetes mellitus screening in dental office.

Effects of β-Glucans Ingestion on Alveolar Bone Loss, Intestinal Morphology, Systemic Inflammatory Profile, and Pancreatic β-Cell Function in Rats with Periodontitis and Diabetes

This study aimed to evaluate the effects of β-glucan ingestion (Saccharomyces cerevisiae) on the plasmatic levels of tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10), alveolar bone loss, and pancreatic β-cell function (HOMA-BF) in diabetic rats with periodontal disease (PD). Besides, intestinal morphology was determined by the villus/crypt ratio. A total of 48 Wistar rats weighing 203 ± 18 g were used. Diabetes was induced by the intraperitoneal injection of streptozotocin (80 mg/kg) and periodontal inflammation, by ligature. The design was completely randomized in a factorial scheme 2 × 2 × 2 (diabetic or not, with or without periodontitis, and ingesting β-glucan or not). The animals received β-glucan by gavage for 28 days. Alveolar bone loss was determined by scanning electron microscopy (distance between the cementoenamel junction and alveolar bone crest) and histometric analysis (bone area between tooth roots). β-glucan reduced plasmatic levels of TNF-α in diabetic animals with PD and of IL-10 in animals with PD (p < 0.05). β-glucan reduced bone loss in animals with PD (p < 0.05). In diabetic animals, β-glucan improved β-cell function (p < 0.05). Diabetic animals had a higher villus/crypt ratio (p < 0.05). In conclusion, β-glucan ingestion reduced the systemic inflammatory profile, prevented alveolar bone loss, and improved β-cell function in diabetic animals with PD.

Cigarette smoke extract (CSE) induces RAGE-mediated inflammation in the Ca9-22 gingival carcinoma epithelial cell line

OBJECTIVE

The oral environment is anatomically positioned as a significant gateway for exposure to environmental toxicants. Cigarette smoke exposure compromises oral health by orchestrating inflammation. The receptor for advanced glycation end-products (RAGE) has been implicated in smoke-induced inflammatory effects; however, its role in the oral cavity is unknown. The purpose of this study was to determine RAGE expression by immortalized gingival carcinoma cells and the degree to which RAGE-mediated signaling influences inflammation.

DESIGN

Gingival epithelia cells (Ca9-22) were exposed to 10% cigarette smoke extract (CSE) for six hours and screened for RAGE expression and inflammatory mediators.

RESULTS

Quantitative PCR and immunoblotting revealed increased RAGE expression following exposure. Furthermore, exposure activated RAGE signaling intermediates including Ras and NF-κB. IL-6 and IL-1β were also elevated in cell culture medium from CSE-exposed cells when compared to controls. A family of anionic, partially lipophilic sulfated polysaccharide derivatives known as semi-synthetic glycosaminoglycan ethers (SAGEs) were used in an effort to block RAGE signaling. Co-treatment of CSE and SAGEs ameliorated inflammatory responses.

CONCLUSIONS

These results provide a new perspective on a mechanism of cigarette smoke induced oral inflammation. Further work may show RAGE signaling as a potential target in the treatment of diseases of the oral cavity exacerbated by tobacco smoke exposure.

Propolis Improves Periodontal Status and Glycemic Control in Patients With Type 2 Diabetes Mellitus and Chronic Periodontitis: A Randomized Clinical Trial

BACKGROUND

Propolis is a natural resin made by bees from various plant sources and exerts antimicrobial, anti-inflammatory, immunomodulatory, antioxidant, and antidiabetic properties. The purpose of this study is to assess adjunctive benefit of propolis supplementation in individuals with chronic periodontitis (CP) and type 2 diabetes mellitus (DMt2) receiving scaling and root planing (SRP).

METHODS

A 6-month masked, randomized clinical trial comparing SRP with placebo (placebo + SRP group, n = 26) or SRP combined with a 6-month regimen of 400 mg oral propolis once daily (propolis + SRP group, n = 24) was performed in patients with long-standing DMt2 and CP. Treatment outcomes included changes in hemoglobin (Hb) A1c (primary outcome), fasting plasma glucose (FPG), serum N^€-(carboxymethyl) lysine (CML), and periodontal parameters (secondary outcomes).

RESULTS

After 3 and 6 months, average HbA1c levels in the propolis group decreased significantly by 0.82% and 0.96% units, respectively (P <0.01); however, there were no significant differences in the placebo group. Likewise, FPG and CML levels were significantly reduced in the propolis group, but not in the placebo group. After therapy, periodontal parameters of CP were significantly improved in both groups. The propolis group showed significantly greater probing depth reduction and clinical attachment level gain than the control group after 3 and 6 months.

CONCLUSION

A 6-month regimen of 400 mg propolis once daily is a potentially viable adjunct to SRP that significantly reduces levels of HbA1c, FPG, and CML, and improves periodontal therapy outcome in people with DMt2 and CP.

Cross-talk between clinical and host-response parameters of periodontitis in smokers

BACKGROUND AND OBJECTIVE

Periodontal diseases are a major public health concern leading to tooth loss and have also been shown to be associated with several chronic systemic diseases. Smoking is a major risk factor for the development of numerous systemic diseases, as well as periodontitis. While it is clear that smokers have a significantly enhanced risk for developing periodontitis leading to tooth loss, the population varies regarding susceptibility to disease associated with smoking. This investigation focused on identifying differences in four broad sets of variables, consisting of: (i) host-response molecules; (ii) periodontal clinical parameters; (iii) antibody responses to periodontal pathogens and oral commensal bacteria; and (iv) other variables of interest, in a population of smokers with (n = 171) and without (n = 117) periodontitis.

MATERIAL AND METHODS

Bayesian network structured learning (BNSL) techniques were used to investigate potential associations and cross-talk between the four broad sets of variables.

RESULTS

BNSL revealed two broad communities with markedly different topology between the populations of smokers, with and without periodontitis. Confidence of the edges in the resulting network also showed marked variations within and between the periodontitis and nonperiodontitis groups.

CONCLUSION

The results presented validated known associations and discovered new ones with minimal precedence that may warrant further investigation and novel hypothesis generation. Cross-talk between the clinical variables and antibody profiles of bacteria were especially pronounced in the case of periodontitis and were mediated by the antibody response profile to Porphyromonas gingivalis.

Correlation between periodontal disease management and metabolic control of type 2 diabetes mellitus. A systematic literature review

Background

Diabetes and periodontal disease share common features in terms of inflammatory responses. Current scientific evidence suggests that treatment of periodontal disease might contribute to glycemic control. The objective of the study is a review of the last three years.

Material and Methods

A literature search was performed in the MEDLINE (PubMed), Cochrane, and Scopus databases, for articles published between 01-01-2013 and 30-06-2015, applying the key terms “periodontal disease” AND “diabetes mellitus”. The review analyzed clinical trials of humans published in English and Spanish.

Results

Thirteen clinical trials were reviewed, representing a total of 1,912 patients. Three of them had samples of <40 patients, making a total of 108 patients and the remaining ten samples had >40 patients, representing a total of 1,804. Only one article achieved a Jadad score of five. Seven articles (998 patients, 52.3% total), presented a statistically significant decrease in HbA1c (p< 0.05) as a result of periodontal treatment. In the six remaining articles (representing 914 patients, 47.8% of the total), the decrease in HbA1c was not significant. Patient follow-up varied between 3 to 12 months. In three articles, the follow-up was of 3, 4, and 9 months, in two 6 and 12 months.

Conclusions

The majority of clinical trials showed that radicular curettage and smoothing, whether associated with antibiotics or not, can improve periodontal conditions in patients with diabetes mellitus. However, few studies suggest that this periodontal treatment improves metabolic control. However, there is no clear evidence of a relation between periodontal treatment and improved glycemic control in patients with type 2 diabetes mellitus.

Key words:Diabetes, periodontal disease, HbA1c, metabolic control.

Dental Implant Sites in Healthy versus Diabetic Subjects: A Two-Year Clinical and Bacteriological Assessment

The aim of this study was to analyze by Real-Time Polymerase Chain Reaction (PCR) possible differences in periimplant microbiota of patients without significant systemic diseases versus patients affected by non-insulin-dependent diabetes mellitus (NIDDM), both treated with dental implants with the same implant-abutment system. Patients suffering from NIDDM, and those with no history of major systemic diseases, treated with dental implants at the Prosthodontics Operative Unit of “Sapienza” University of Rome in the period February 2009 - March 2010 were considered. Clinical parameters as well as microbiological profile were evaluated for each implant site at 3, 6,12, and 24 month follow-up. Crevicular fluid was collected for microbial sampling and analyzed by Real-Time PCR in order to identify the possible presence of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum and Prevotella intermedia. Eight patients suffering from NIDDM and 22 with no history of major systemic diseases were included in the present investigation, each having received one to three dental implants. All the implants had been loaded 3 months after surgery, and the average follow-up after implant placement was 26.37±3.86. Clinical parameters showed no noticeable difference between the two groups, except for the Implant Stability Quotient (ISQ) that showed significantly lower values in NIDDM patients. A slightly higher amount of the considered pathogenic bacteria were retrieved in samples collected from patients with NIDDM (7.38×105) in comparison with those of healthy subjects (6.78×105), though the differences were below statistical significance. Within the limitations of the present study, a slight correlation was empirically detected between gene expression profiles of microbial populations and history of NIDDM, which however remained below the statistical significance. Further well-designed clinical studies may be useful to conclusively clarify the impact of subgingival microflora on the increased susceptibility of diabetic patients to periimplantitis.

Periodontal dysbiosis linked to periodontitis is associated with cardiometabolic adaptation to high-fat diet in mice

Periodontitis and type 2 diabetes are connected pandemic diseases, and both are risk factors for cardiovascular complications. Nevertheless, the molecular factors relating these two chronic pathologies are poorly understood. We have shown that, in response to a long-term fat-enriched diet, mice present particular gut microbiota profiles related to three metabolic phenotypes: diabetic-resistant (DR), intermediate (Inter), and diabetic-sensitive (DS). Moreover, many studies suggest that a dysbiosis of periodontal microbiota could be associated with the incidence of metabolic and cardiac diseases. We investigated whether periodontitis together with the periodontal microbiota may also be associated with these different cardiometabolic phenotypes. We report that the severity of glucose intolerance is related to the severity of periodontitis and cardiac disorders. In detail, alveolar bone loss was more accentuated in DS than Inter, DR, and normal chow-fed mice. Molecular markers of periodontal inflammation, such as TNF-α and plasminogen activator inhibitor-1 mRNA levels, correlated positively with both alveolar bone loss and glycemic index. Furthermore, the periodontal microbiota of DR mice was dominated by the Streptococcaceae family of the phylum Firmicutes, whereas the periodontal microbiota of DS mice was characterized by increased Porphyromonadaceae and Prevotellaceae families. Moreover, in DS mice the periodontal microbiota was indicated by an abundance of the genera Prevotella and Tannerella, which are major periodontal pathogens. PICRUSt analysis of the periodontal microbiome highlighted that prenyltransferase pathways follow the cardiometabolic adaptation to a high-fat diet. Finally, DS mice displayed a worse cardiac phenotype, percentage of fractional shortening, heart rhythm, and left ventricle weight-to-tibia length ratio than Inter and DR mice. Together, our data show that periodontitis combined with particular periodontal microbiota and microbiome is associated with metabolic adaptation to a high-fat diet related to the severity of cardiometabolic alteration.

Statin intake is associated with MMP-1 level in gingival crevicular fluid of patients with periodontitis

BACKGROUND

This study was conducted to assess whether statin intake is associated with clinical parameters of periodontitis and matrix metalloproteinase (MMP) levels in gingival crevicular fluid (GCF) of non-diabetic and diabetic patients.

METHODS

We first determined the effect of simvastatin on MMP expression in mononuclear cells. We then recruited 117 non-diabetic and diabetic patients, who all had periodontitis and took or did not take statin, and measured periodontal probing depth (PPD) and clinical attachment level (CAL), and collected gingival crevicular fluid (GCF) to quantify MMPs.

RESULTS

The in vitro studies showed that simvastatin potently inhibited the expression of MMP-1, MMP-8, and MMP-9 upregulated by lipopolysaccharide (LPS) and high glucose in mononuclear cells. The patient study showed that, after adjusting for age and smoking status, PPD in diabetic patients on statin was significantly less than that in diabetic patients not on statin. MMP-1 level in GCF of non-diabetic and diabetic patients on statin was lower than that of non-diabetic and diabetic patients not on statin, respectively. No difference was found for MMP-8 and -9 levels in GCF.

CONCLUSION

Statin intake is associated with reduced PPD in diabetic patients and MMP-1 level in GCF in either non-diabetic or diabetic patients.

A review of the evidence for pathogenic mechanisms that may link periodontitis and diabetes

AIMS

To review the evidence for the molecular and cellular processes that may potentially link periodontal disease and diabetes. The pathogenic roles of cytokines and metabolic molecules (e.g. glucose, lipids) are explored and the role of periodontal bacteria is also addressed. Paradigms for bidirectional relationships between periodontitis and diabetes are discussed and opportunities for elaborating these models are considered.

METHODS

Database searches were performed using MeSH terms, keywords, and title words. Studies were evaluated and summarized in a narrative review.

RESULTS

Periodontal microbiota appears unaltered by diabetes and there is little evidence that it may influence glycaemic control. Small-scale clinical studies and experiments in animal models suggest that IL-1β, TNF-α, IL-6, OPG and RANKL may mediate periodontitis in diabetes. The AGE-RAGE axis is likely an important pathway of tissue destruction and impaired repair in diabetes-associated periodontitis. A role for locally activated pro-inflammatory factors in the periodontium, which subsequently impact on diabetes, remains speculative.

CONCLUSION

There is substantial information on potential mechanistic pathways which support a close association between diabetes and periodontitis, but there is a real need for longitudinal clinical studies using larger patient groups, integrated with studies of animal models and cells/tissues in vitro.

Relationship of Routine Inadequate Sleep Duration and Periodontitis in a Nationally Representative Sample

Purpose. Previous research has indicated the public health impact of inadequate sleep duration on health, potentially through an immune-inflammation mechanism. This mechanism also has a role in periodontitis. The purpose of this study is to determine if there is an association of routine inadequate sleep and periodontitis. Methods. Data from merged National Health and Nutrition Examination Survey years 2009-10 and 2011-12 were the data source for the study. The key outcome was periodontitis (yes, no), and the key variable of interest was usual sleep on weekday or workday nights. Chi square and logistic regression procedures were conducted. The study included 3,740 participants who were of ages 30 years and above. Results. There were 52.7% of participants who had periodontitis. There were 35.7% who usually slept less than 7 hours on weekday or workday nights. In adjusted logistic regression the odds ratio for periodontal disease for participants who slept less than 7 hours on weekday or workday night was 1.00 [95% confidence interval: 0.83, 1.21; p = .9812]. Conclusions. The relationship of periodontitis and inadequate sleep duration in a nationally representative study of participants who were of ages 30 years and above failed to reach statistical significance in adjusted logistic regression analyses.

Systemic inflammatory responses in patients with type 2 diabetes with chronic periodontitis

OBJECTIVE

The objective of this case-control study was to quantify the immune responsiveness in individuals with type 2 diabetes (T2D) as compared with patients without diabetes (NT2D) diagnosed with periodontitis.

RESEARCH DESIGN AND METHODS

Peripheral blood was collected from 20 patients with moderate-to-severe chronic periodontitis (10 T2D, 10 NT2D). Blood samples were stimulated with ultrapure Porphyromonas gingivalis and Escherichia coli lipopolysaccharide (LPS) for 24 hours. 14 cytokines/chemokines were quantified in culture supernatants using multiplex technology.

RESULTS

T2D individuals demonstrated higher unstimulated levels of interleukin 6 (IL-6), IL-1β, tumor necrosis factor α, interferon γ, IL-10, IL-8, macrophage inflammatory protein 1α (MIP1α), and 1β (MIP1β), and higher stimulated levels of IL-6, IL-8, IL-10, MIP1α and MIP1β, along with lower unstimulated and stimulated levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) when compared with NT2D (p<0.05). Importantly, the LPS-induced levels of IL-6, IL-8, IL-10 and MIP1α strongly correlated with severity of disease, measured by pocket depths (PD), within the T2D group (r(2)≥0.7, p<0.05), but not within NT2D.

CONCLUSIONS

Among patients with chronic periodontitis, patients with T2D seem to have an enhanced LPS-induced immune responsiveness than individuals without diabetes, which correlates with periodontal disease severity, concomitant with a less robust GM-CSF response. This data may in part explain the higher predisposition to periodontitis in this population.

Candida spp. and gingivitis in children with nephrotic syndrome or type 1 diabetes

Background

Diabetes and Nephrotic syndrome (NS) promote plaque-related gingivitis and yeast-like fungal infections.

The study assesses the impact of Candida spp. and general disease- or treatment-related factors on plaque-related gingivitis severity in children and adolescents with Nephrotic syndrome /diabetes.

Methods

Body mass index (BMI), BMI standard deviation score, and oral cavity (Plaque Index – PLI, Gingival Index – GI, mucosa status, presence and Candida enzymatic activity) were assessed in 96 patients (32 with NS: 30- immunosuppressive treatment, 35 - type 1 diabetes, and 29 generally healthy), aged; 3–18 years. Laboratory included cholesterol and triglyceride measurements; in diabetic subjects– glycated haemoglobin, in NS: total protein, albumin, creatinine, haemoglobin, haematocrit, white cell count, urinary protein excretion. Medical records supplied information on disease duration and treatment. A statistical analysis was performed; Kendall Tau coefficient, chi-square test, t-test, and multiple regression analysis ( P < 0.05).

Results

Candida spp. often occurred in healthy patients, but oral candidiasis was found only in the NS and diabetes groups (9.37% and 11.43%). Gingivitis occurred more frequently in patients with NS/diabetes. Gingivitis severity was correlated with PLI, age, and yeast enzyme activity in NS – to with immunosuppressive treatment with >1 drug, drug doses, treatment duration, lipid disorders, and BMI; in diabetes, with blood glucose and glycated haemoglobin >8%.

Conclusion

Poor hygiene control is the main cause of gingivitis. Gingivitis severity is most likely related to age, lipid disorders and increase in body mass. Candida spp., in uncompensated diabetes and in those using immunosuppressive treatment, might intensify plaque-related gingivitis.

Periodontitis and type II diabetes: a two-way relationship

For many years an association between diabetes and periodontitis has been suspected. In more recent times this relationship has been suggested to be bidirectional with each condition being able to influence the other. In this review the two-way relationship between diabetes and periodontitis is considered. For this narrative review a very broad search strategy of the literature was developed using both EMBASE and MEDLINE (via PubMed) databases. The reference lists from the selected papers were also scanned, and this provided an additional source of papers for inclusion and further assessment. The data available suggest that diabetes is a risk as well as a modifying factor for periodontitis. Individuals with diabetes are more likely to have periodontitis and with increased severity when diabetes is uncontrolled/poorly controlled. Possible mechanisms of how diabetes affects periodontitis include adipokine-mediated inflammation, neutrophil dysfunction, uncoupling of bone and advanced glycation end-products-receptor for advanced glycation end-products interaction. Evidence is accruing to support how periodontitis can affect diabetes and complications associated with diabetes. There is some evidence demonstrating that periodontal therapy can result in a moderate improvement in glycaemic control. Available evidence indicates that diabetes and peridontitis are intricately interrelated and that each condition has the capacity to influence clinical features of each other.

Increased and correlated expression of connective tissue growth factor and transforming growth factor beta 1 in surgically removed periodontal tissues with chronic periodontitis

BACKGROUND AND OBJECTIVE

Both gingival tissue destruction and regeneration are associated with chronic periodontitis, although the former overwhelms the latter. Studies have shown that transforming growth factor beta 1 (TGF-β1), a growth factor largely involved in tissue regeneration and remodeling, is upregulated in chronic periodontitis. However, the gingival expression of connective tissue growth factor (CTGF or CCN2), a TGF-β1-upregulated gene, in patients with periodontitis remains undetermined. Although both CTGF/CCN2 and TGF-b1 increase the production of extracellular matrix, they have many different biological functions. Therefore, it is important to delineate the impact of periodontitis on gingival CTGF/CCN2 expression.

MATERIAL AND METHODS

Periodontal tissue specimens were collected from seven individuals without periodontitis (group 1) and from 14 with periodontitis (group 2). The expression of CTGF and TGFβ1 mRNAs were quantified using real-time PCR.

RESULTS

Analysis using the nonparametric Mann-Whitney U-test showed that the levels of expression of both CTGF/CCN2 and TGFβ1 mRNAs were significantly increased in individuals with periodontitis compared with individuals without periodontitis. Furthermore, analysis using a nonparametric correlation (Spearman r) test showed a positive correlation between TGFβ1 and CTGF/CCN2 mRNAs.

CONCLUSION

The gingival expression levels of CTGF/CCN2 and TGFβ1 mRNAs in individuals with periodontitis are upregulated and correlated.

The effect of periodontal therapy on glycaemic control in a Hispanic population with type 2 diabetes: a randomized controlled trial

OBJECTIVE

In the Mexican-American population, the prevalence of Type 2 diabetes mellitus (T2DM) is as high as 50% of the population. This randomized controlled clinical trial was designed to elucidate how treatment of periodontal disease affects HbA1c values in this population.

MATERIALS AND METHODS

One hundred and fifty-four T2DM patients with periodontal disease were enrolled in the study. The test group was treated with scaling and root planing (SRP); the control group received oral hygiene instructions. At baseline and 4-6 weeks after therapy, a complete periodontal examination was performed. Blood was collected at baseline and 4 months later for HbA1c levels.

RESULTS

One hundred and twenty-six individuals completed the study. Baseline mean ± SD HbA1c for the test and control groups were 9.0 ± 2.3% and 8.4 ± 2.0% respectively. Non-significant difference in HbA1c reductions (0.6 ± 2.1% and 0.3 ± 1.7%) was found between test and control groups at 4 months. Comparisons of the periodontal clinical parameters between the test and control groups found significant differences with improved results in the test subjects.

CONCLUSIONS

No statistically significant differences were found in the changes of HbA1c levels between test and control groups. Non-surgical periodontal therapy improved the magnitude of change in periodontal parameters as compared to the control subjects. ClinicalTrials.gov Identifier: NCT01128374.

Cytokines in patients with type 2 diabetes and chronic periodontitis: A systematic review and meta-analysis

Individuals with type 2 diabetes mellitus (T2DM) and chronic periodontitis have significantly higher levels of interleukin-1 beta compared with systemically healthy individuals with chronic periodontitis. However, there was no significant difference in gingival crevicular levels of other cytokines between individuals with and without T2DM.

Risk factors for periodontal disease

Risk factors play an important role in an individual's response to periodontal infection. Identification of these risk factors helps to target patients for prevention and treatment, with modification of risk factors critical to the control of periodontal disease. Shifts in our understanding of periodontal disease prevalence, and advances in scientific methodology and statistical analysis in the last few decades, have allowed identification of several major systemic risk factors for periodontal disease. The first change in our thinking was the understanding that periodontal disease is not universal, but that severe forms are found only in a portion of the adult population who show abnormal susceptibility. Analysis of risk factors and the ability to statistically adjust and stratify populations to eliminate the effects of confounding factors have allowed identification of independent risk factors. These independent but modifiable, risk factors for periodontal disease include lifestyle factors, such as smoking and alcohol consumption. They also include diseases and unhealthy conditions such as diabetes mellitus, obesity, metabolic syndrome, osteoporosis, and low dietary calcium and vitamin D. These risk factors are modifiable and their management is a major component of the contemporary care of many periodontal patients. Genetic factors also play a role in periodontal disease and allow one to target individuals for prevention and early detection. The role of genetic factors in aggressive periodontitis is clear. However, although genetic factors (i.e., specific genes) are strongly suspected to have an association with chronic adult periodontitis, there is as yet no clear evidence for this in the general population. It is important to pursue efforts to identify genetic factors associated with chronic periodontitis because such factors have potential in identifying patients who have a high susceptibility for development of this disease. Many of the systemic risk factors for periodontal disease, such as smoking, diabetes and obesity, and osteoporosis in postmenopausal women, are relatively common and can be expected to affect most patients with periodontal disease seen in clinics and dental practices. Hence, risk factor identification and management has become a key component of care for periodontal patients.