Metabolic syndrome and periodontitis: is oxidative stress a common link?

The effectiveness of a self-reported questionnaire on masticatory function in health examinations

Periodontal diseases have been reported to be lifestyle-related and associated with metabolic syndrome (MetS). The introduction of dental checkups in a health checkup program may create a synergistic effect and aid the prevention of MetS. In Japan, a chewing function questionnaire has now been introduced into the national health checkup program. The purpose of this study was to investigate whether the questionnaire reflects dental and oral conditions and whether it helps improve general and oral health. A total of 6599 subjects who underwent health checkups or guidance specified by the National Health Insurance of Japan for two consecutive years were included. A single comprehensive question to evaluate masticatory function was asked. Medical and dental examinations and insurance data were collected and used for analysis. In terms of masticatory function during chewing, 82.3% of subjects experienced no problems, 17.3% experienced some difficulty, and 0.4% experienced severe problems. There was a significant relationship between the questionnaire response and dental examinations results for several items of examination. The overall dental consultation rate after health screening was 42.3%. Improvement in periodontal disease was achieved in those who reported some problems with chewing function. Improvement in blood pressure was also observed in those who reported some problem with chewing function and subsequently had a dental consultation. The results of this study indicate that questionnaires on masticatory function reflect the status of dental and oral health. In addition, the results suggested that questionnaire results are potentially linked to improvement in dental and oral health status, and improvement in MetS.

The Potential Effect of Periodontal Disease on the Development of Metabolic Syndrome: A 10-Year Observational Study in a Thai Adult Cohort

AIM

As data are sparse on the long-term association between periodontal diseases and development of metabolic syndrome (MetS), we investigated their relationship in a Thai cohort over a 10-year observational period.

METHODS

Medical records and data on periodontal assessments of 2161 employees of the Electricity Generating Authority of Thailand collected at two time points, 2003 and 2013, were used. Experienced periodontists used standard national and international criteria to define periodontitis and MetS. The impact of baseline periodontitis on subsequent MetS incidence and its components was evaluated using regression analyses.

RESULTS

The severity and extent of periodontitis significantly predicted MetS incidence over a decade, with a higher incidence of MetS in individuals with poorer periodontal health. A single percentage increase in the periodontitis extent raised the risk of MetS incidence by 0.4% and the risk of developing individual components of MetS by 0.2%. Independent of periodontal health, age of an individual emerged as a factor impacting MetS development.

CONCLUSION

This study highlights the potential effect of the severity and extent of periodontitis on the increased incidence and progression of MetS. Hyperglycaemia and hypertension were the two MetS components most significantly affected by the existence of periodontitis.

Improvement of post-periodontitis-therapy inflammatory state in diabetics: a meta-analysis of randomized controlled trials

OBJECTIVES

This systematic review aimed to evaluate the impact of periodontal therapy on systemic biomarkers of inflammation and oxidative stress in patients with type 2 diabetes mellitus (T2DM) and periodontitis.

MATERIALS AND METHODS

An electronic search without restriction on dates or languages was performed in six electronic databases, protocol records and other sources until May 2024. To develop the search strategy, clinical question was formulated using the PICOD method. Eligibility criteria included randomized controlled trials on the effects of periodontitis-therapy on the inflammatory parameters of T2DM patients. Risk of bias and certainty of evidence were assessed by RoB2 and GRADE tools, respectively. The review protocol was registered in PROSPERO platform (CRD42020206295).

RESULTS

Of 1,062 records screened, the authors determined that 14 studies enrolling 1223 participants proved eligible. Moderate-quality evidence suggested a positive effect of periodontitis-therapy on serum levels of c-reactive protein [0.39 (CI95%: 0.27-0.5)], even without the use of antibiotics [0.34 (CI95%: 0.22-0.46)], in T2DM patients. The significant reduction in C-reactive protein (CRP) among smokers in favor of periodontitis-therapy was greatest at six months of follow-up.

CONCLUSIONS

Non-surgical periodontal therapy improved short-term biomarkers of systemic inflammation in T2DM patients, with moderate evidence of improvement in serum levels of high sensitivity-CRP.

CLINICAL RELEVANCE

Systemic inflammation in T2DM patients can be reduced after non-surgical periodontal therapy, which also has the potential to reduce the risk of other important systemic outcomes, such as cardiovascular disease.

Interlinked Pathways: Exploring the Bidirectional Impacts of Periodontitis and Metabolic Syndrome

Metabolic syndrome (MBS) and periodontitis are distinct conditions with overlapping and unique risk factors. Periodontitis is a chronic destructive disease of the periodontium, driven by alterations in the host immune-inflammatory response to virulent periodontal pathogens. MBS is characterized by various abnormalities, including visceral abdominal obesity, dyslipidemia (low high-density lipoprotein (HDL) and high triglyceride (TG) levels), hypertension, and hyperglycemia. These factors collectively increase the risk of atherosclerotic cardiovascular disease (CVD) and diabetes. Several pro-inflammatory mediators are involved in the pathogenesis of periodontitis and MBS, and the deleterious bidirectional effects of these mediators exacerbate the severity and progression of both conditions. This comprehensive review focuses on the intricate relationship between MBS and periodontitis. Specifically, it explores the pathophysiological mechanisms of each disease component of MBS and its impact on periodontitis, and vice versa.

The role of periodontitis in the development of atherosclerotic cardiovascular disease in participants with the components of metabolic syndrome: a systematic review and meta-analysis

OBJECTIVES

Prevention of atherosclerotic cardiovascular disease (ASCVD) is important in individuals with metabolic syndrome components (MetS), and periodontitis may play an important role in this process. This study aims to evaluate the association between periodontitis and ASCVD in participants with the components of MetS, including obesity, dysglycemia, hypertension, and dyslipidemia.

MATERIALS AND METHODS

This study conducted followed the MOOSE reporting guidelines and the PRISMA 2020 guidelines. EMBASE, MEDLINE, Web of Science, Cochrane Library, PubMed and OpenGrey were searched for observational studies about the linkage of periodontitis to ASCVD in people with MetS components up to April 9, 2023. Cohort, case-control and cross-sectional studies were included after study selection. Quality evaluation was carried out using the original and modified Newcastle-Ottawa Scale as appropriate. Random-effects model was employed for meta-analysis.

RESULTS

Nineteen studies were finally included in the quality analysis, and all of them were assessed as moderate to high quality. Meta-analyses among fifteen studies revealed that the participants with periodontitis were more likely to develop ASCVD in those who have dysglycemia (RR = 1.25, 95% CI = 1.13-1.37; p < 0.05), obesity (RR = 1.13, 95% CI = 1.02-1.24; p < 0.05), dyslipidemia (RR = 1.36, 95% CI = 1.13-1.65; p < 0.05), or hypertension (1.20, 95% CI = 1.05-1.36; p < 0.05).

CONCLUSIONS

Periodontitis promotes the development of ASCVD in participants with one MetS component (obesity, dysglycemia, hypertension or dyslipidemia).

CLINICAL RELEVANCE

In people with MetS components, periodontitis may contribute to the ASCVD incidence.

Sports Diet and Oral Health in Athletes: A Comprehensive Review

Food and fluid supply is fundamental for optimal athletic performance but can also be a risk factor for caries, dental erosion, and periodontal diseases, which in turn can impair athletic performance. Many studies have reported a high prevalence of oral diseases in elite athletes, notably dental caries 20-84%, dental erosion 42-59%, gingivitis 58-77%, and periodontal disease 15-41%, caused by frequent consumption of sugars/carbohydrates, polyunsaturated fats, or deficient protein intake. There are three possible major reasons for poor oral health in athletes which are addressed in this review: oxidative stress, sports diet, and oral hygiene. This update particularly summarizes potential sports nutritional effects on athletes' dental health. Overall, sports diet appropriately applied to deliver benefits for performance associated with oral hygiene requirements is necessary to ensure athletes' health. The overall aim is to help athletes, dentists, and nutritionists understand the tangled connections between sports diet, oral health, and oral healthcare to develop mitigation strategies to reduce the risk of dental diseases due to nutrition.

Emerging factors affecting peri-implant bone metabolism

Implant dentistry has evolved to the point that standard implant osseointegration is predictable. This is attributed in part to the advancements in material sciences that have led toward improvements in implant surface technology and characteristics. Nonetheless, there remain several cases where implant therapy fails (specifically at early time points), most commonly attributed to factors affecting bone metabolism. Among these patients, smokers are known to have impaired bone metabolism and thus be subject to higher risks of early implant failure and/or late complications related to the stability of the peri-implant bone and mucosal tissues. Notably, however, emerging data have unveiled other critical factors affecting osseointegration, namely, those related to the metabolism of bone tissues. The aim of this review is to shed light on the effects of implant-related factors, like implant surface or titanium particle release; surgical-related factors, like osseodensification or implanted biomaterials; various drugs, like selective serotonin reuptake inhibitors, proton pump inhibitors, anti-hypertensives, nonsteroidal anti-inflammatory medication, and statins, and host-related factors, like smoking, diet, and metabolic syndrome on bone metabolism, and aseptic peri-implant bone loss. Despite the infectious nature of peri-implant biological complications, these factors must be surveyed for the effective prevention and management of peri-implantitis.

Identifying Oxidative Stress-Related Genes (OSRGs) as Potential Target for Treating Periodontitis Based on Bioinformatics Analysis

BACKGROUND

Periodontitis (PD) is a multifactorial inflammatory disease that is closely associated with periodontopathic bacteria. Numerous studies have demonstrated oxidative stress (OS) contributes to inflammation and is a prime factor in the development of PD. It is imperative to explore the function of newly discovered hub genes associated with OS in the advancement of PD, thereby identifying potential targets for therapeutic intervention.

OBJECTIVES

The goal of the current study was to identify the oxidative-stress-related genes (OSRGs) associated with periodontitis (PD) development using an integrated bioinformatics method.

METHODS

DEGs from GEO gene-expression data were identified using the "limma" package. We obtained OSRGs from GeneCards and utilized a Venn diagram to uncover differentially expressed OSRGs (DEOSRGs). After receiving the DEOSRGs, we employed Gene Ontology (GO), Kyoto Encyclopaedia of Genes and Genomes (KEGG), and protein-protein interaction (PPI) analytical tools to examine their possible functions and pathways in PD. Receiver operating characteristic (ROC) curves screened for hub genes of PD. RT-qPCR and western blot analysis were used to detect DEOSRG expression in mouse ligature-induced periodontitis gingival tissues.

RESULTS

The investigation identified 273 OSRGs. Based on PPI analysis, we recognized 20 OSRGs as hub genes. GO and KEGG enrichment analysis indicated that these hub genes were predominantly enriched in leukocyte migration, lymphocyte proliferation, and humoral immune response, and associated with leukocyte trans-endothelial migration, cytokine-cytokine receptor interaction, and NF-κB signaling pathway. Following ROC analysis, VCAM1, ITGAM, FCGR3A, IL1A, PECAM1, and VCAM1were identified as PD prognostic gene. RT-qPCR and western blot analyses confirmed that the expression ITGAM, FCGR3A, and PECAM1 were significantly elevated in the gingival tissues obtained from mice.

CONCLUSION

This investigation revealed that ITGAM, FCGR3A, and PECAM1 may have a crucial function in the advancement of PD.

The relationship between leptin and periodontitis: a literature review

Leptin is a peptide hormone that regulates energy balance, immune inflammatory response, and bone metabolism. Several studies have demonstrated a relationship between leptin and periodontitis, a local inflammatory disease that progressively weakens the supporting structures of the teeth, eventually leading to tooth loss. This article reviews the existing literature and discusses leptin's basic characteristics, its relationship with periodontitis, and its effects on periodontal tissue metabolism.

Investigation on the association between serum lipid levels and periodontitis: a bidirectional Mendelian randomization analysis

OBJECTIVE

Several research has considered the potential correlation between periodontitis and serum lipids. However, serum lipid profiles correlation with periodontitis remains largely unknown. The investigation objective was to examine periodontitis correlation with serum lipid levels using a bidirectional Mendelian randomization (MR) analysis.

METHODS

The study employed a bidirectional MR analysis with two samples, utilizing a freely accessible genome-wide association study (GWAS). Furthermore, the primary analysis employed the inverse variance weighted (IVW) method. To determine whether the lipid profiles were associated with periodontitis, a variety of sensitivity analyses (including MR-Egger regression, MR-PRESSO, and weighted median), as well as multivariable MR, were employed.

RESULTS

MR analysis performed by IVW did not reveal any relationship between periodontitis and low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG), or total cholesterol (TC). It was also found that LDL, HDL, TG, and TC were not associated to periodontitis. Furthermore, the MR estimations exhibited consistency with other MR sensitivity and multivariate MR (MVMR) analyses. These results show that the correlation between serum lipid levels and periodontitis could not be established.

CONCLUSION

The finding indicates a negligible link between periodontitis and serum lipid levels were identified, despite previous observational studies reporting a link between periodontitis and serum lipid levels.

Type 2 Diabetes Mellitus and Periodontitis: Bidirectional Association in Population-based 15-year Retrospective Cohorts

OBJECTIVE

A two-way relationship between periodontitis and diabetes has been proposed. However, bidirectional epidemiological observation is limited and inconsistent.

OBJECTIVE

Using the National Health Insurance Research Database of Taiwan (covering over 99% of the entire population), we aimed to estimate the development of diabetes in periodontitis patients or that of periodontitis in patients with type 2 diabetes mellitus (T2DM), respectively.

METHODS

A total of 11 011 patients with severe periodontitis were recruited from 2000 to 2015. After matching by age, sex, and index date, 11 011 patients with mild periodontitis and 11 011 non-periodontitis controls were registered. Additionally, 157 798 patients with T2DM and 157 798 non-T2DM controls were enrolled, in whom the development of periodontitis was traced. Cox proportional hazards model was performed.

RESULTS

Periodontitis patients tended to have a statistically high risk for T2DM. The adjusted hazard ratio was 1.94 (95% CI, 1.49-2.63, P < .01) and 1.72 (95% CI, 1.24-2.52, P < .01) for severe and mild periodontitis groups, respectively. The patients with severe periodontitis had a higher risk of having T2DM relative to those with mild periodontitis (1.17 [95% CI, 1.04-1.26, P < .001]). Conversely, the risk of periodontitis increased significantly in patients with T2DM (1.99 [95% CI, 1.42-2.48, P < .01]). However, high risk was observed for the outcome of severe periodontitis (2.08 [95% CI, 1.50-2.66, P < .001]), but not for mild periodontitis (0.97 [95% CI, 0.38-1.57, P = .462]).

CONCLUSION

We suggest that the bidirectional association is between T2DM and severe but not mild periodontitis.

Thioredoxin-1 promotes the restoration of alveolar bone in periodontitis with diabetes

Treatment of periodontitis in people with diabetes remains challenging. The present study aimed to investigate the therapeutic potential of thioredoxin-1 (TRX1) in periodontitis with diabetes, as well as its role in modulating osteogenic differentiation. Our findings indicated that the production of reactive oxygen species (ROS) was elevated, while the expression of TRX1 was significantly reduced in the periodontal tissues of periodontitis mice with diabetes. Furthermore, knockdown of TRX1 in periodontal ligament stem cells (PDLSCs) resulted in the inhibition of osteogenic differentiation through disrupting Wnt/β-catenin signaling. However, this inhibition was restored upon administration of recombinant human TRX1 (rhTRX1). Importantly, rhTRX1 treatment decreased ROS generation, activated Wnt/β-catenin signal pathway and considerably promoted the alveolar bone repair of periodontitis mice with diabetes. These findings highlighted the crucial protective role of TRX1 in periodontitis with diabetes and suggested that it may serve as a potential therapeutic target for refractory periodontitis associated with oxidative stress.

Periodontal Disease Treatment After Stroke or Transient Ischemic Attack: The PREMIERS Study, a Randomized Clinical Trial

BACKGROUND

Patients with stroke/transient ischemic attack and periodontal disease (PD) are at increased risk for cardiovascular events. PD treatments that can improve stroke risk factors were tested if they might assist patients with cerebrovascular disease.

METHODS

In this multicenter phase II trial, patients with stroke/transient ischemic attack and moderately severe PD were randomly assigned to intensive or standard PD treatment arms. The primary outcome measure was a composite of death, myocardial infarction, and recurrent stroke, as well as adverse events. Secondary outcome included changes in stroke risk factors.

RESULTS

A total of 1209 patients with stroke/transient ischemic attack were screened, of whom 481 met the PD eligibility criteria; 280 patients were randomized to intensive arm (n=140) and standard arm (n=140). In 12-month period, primary outcome occurred in 11 (8%) in the intensive arm and 17 (12%) in the standard arm. The intensive arm was nonsuperior to the standard arm (hazard ratio, 0.65 [95% CI, 0.30-1.38]) with similar rates of adverse events (sepsis 2.1% versus 0.7%; dental bleeding 1.4% versus 0%; and infective endocarditis 0.7% versus 0%). Secondary-outcome improvements were noted in both arms with diastolic blood pressure and high-density lipoprotein cholesterol (P<0.05).

CONCLUSIONS

In patients with recent stroke/transient ischemic attack and PD, intensive PD treatment was not superior to standard PD treatment in prevention of stroke/myocardial infarction/death. Fewer events were noted in the intensive arm and the 2 arms were comparable in the safety outcomes. Secondary-outcome measures showed a trend toward improvement, with significant changes noted in diastolic blood pressure and high-density lipoprotein in both the treatment arms.

Silibinin alleviates inflammation-induced bone loss by modulating biological interaction between human gingival fibroblasts and monocytes

BACKGROUND

Silibinin has shown various pharmacological effects that could be attributed to its antioxidant, anti-inflammatory, and immunoregulatory properties. However, the therapeutic potential of silibinin for periodontitis has not been investigated.

METHODS

The therapeutic effects of silibinin in ligation-induced experimental periodontitis were investigated using biochemical, histological, and immunohistochemical methods. The effects of silibinin on the osteoclastogenesis of RAW264.7 cells were investigated using TRAP staining, quantitative polymerase chain reaction (qPCR), pit formation, and immunoblotting. Moreover, its effects on inflammatory cytokine production, RANKL expression, and oxidative stress in lipopolysaccharide (LPS)-stimulated human gingival fibroblasts (HGFs) were evaluated using qPCR and flow cytometry. A coculture system was established to elucidate the effects of silibinin on the crosstalk between LPS-stimulated HGFs and undifferentiated monocytes.

RESULTS

Silibinin significantly reduced the alveolar bone loss, decreased the gingival inflammation and RANKL expression, and decreased the RANKL/osteoprotegerin ratio in gingival tissues in experimental periodontitis. The in vitro results showed that silibinin inhibited RANKL-induced osteoclast differentiation and function of RAW264.7 cells and suppressed RANKL-induced nuclear factor of activated T cells 1 (NFATc1) induction and translocation through the nuclear factor-κB and mitogen-activated protein kinase signaling pathways. Silibinin decreased the inflammatory cytokine level and oxidative stress production in LPS-stimulated HGFs; significantly suppressed membrane-bound RANKL expression on LPS-stimulated HGFs; and significantly disrupted TRAP+ cell differentiation in the coculture system.

CONCLUSIONS

Silibinin effectively inhibits inflammation-induced bone loss in experimental periodontitis based on the regulation of stimulated HGFs by inhibiting the expression of inflammatory and osteoclastogenic mediators. Collectively, targeting the inflamed HGF resolution that mediates osteogenesis may use silibinin as a potential drug-repurposing candidate for modulating alveolar bone destruction in periodontitis.

SUMMARY

Silibinin effectively inhibits inflammation-induced bone loss in experimental periodontitis based on the regulation of stimulated HGFs by inhibiting the expression of inflammatory and osteoclastogenic mediators.

Periodontitis in obese adults with and without metabolic syndrome: a cross-sectional study

BACKGROUND

Epidemiological studies support an association between obesity, metabolic syndrome (MetS), and periodontitis. Still, understanding of the effects of low-grade inflammation in obese subjects on periodontitis and influence of MetS remains incomplete. The aims of this cross-sectional study were to explore the association between obesity related variables and periodontitis, and assess if MetS is a risk indicator for periodontitis in a sample of obese adults.

METHODS

The study sample comprised 52 adults with a body mass index (BMI) of ≥ 30 kg/m2 referred for obesity therapy at the Obesity Centre at Haukeland University Hospital (HUH), Bergen, Norway. The subjects had prior to enrolment completed a 5-month lifestyle intervention course as part of a 2-year managing program. According to the revised National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) classification of MetS, 38 subjects were recruited to the MetS group and 14 subjects to the non-MetS group. Medical data including peripheral blood samples were obtained from records at HUH at the time of enrolment. Probing depth, clinical attachment level, tooth mobility, furcation involvement, bleeding on probing (BoP) were recorded and intraoral bitewings evaluated at a full-mouth periodontal examination. Associations between risk variables for obesity/MetS and periodontitis were explored using linear and logistic regression models.

RESULTS

In the present sample 79% of the subjects were diagnosed with periodontitis. The prevalence of stage III/IV periodontitis was 42.9% in the non-MetS group vs. 36.8% in the MetS group (p = 0.200). In the non-MetS group 29.8% of the sites displayed BoP vs. 23.5% in the MetS group (p = 0.048). For stage III/IV periodontitis, the effect of age appeared to be significant for obesity related variables and MetS (p = 0.006, p = 0.002, respectively). None of the other analyses showed significant association with the outcome variables.

CONCLUSION

In the present sample of obese subjects, periodontitis occurred independently of MetS. Reaching a certain BMI level, suggested association between MetS and periodontitis might be non-significant due to the dominating impact of obesity related variables undermining the effect of other systemic factors.

TRIAL REGISTRATION

The principal clinical trial, entitled "Obesity and Oral Diseases", was prospectively registered in ClinicalTrials.gov with registration NCT04602572 (20.10.2020).

Association between metabolic syndrome components and gingival bleeding is women-specific: a nested cross-sectional study

BACKGROUND

Metabolic syndrome (MetS) is a cluster of atherosclerotic risk factors that increases cardiovascular risk. MetS has been associated with periodontitis, but the contribution of single MetS components and any possible sexual dimorphism in this relation remain undetermined.

METHODS

Using the third National Health and Nutrition Examination Survey (NHANES III), we performed a nested cross-sectional study to test whether individuals aged > 30 years undergoing periodontal evaluation (population) exposed to ≥ 1 MetS component (exposure) were at increased risk of bleeding/non-bleeding periodontal diseases (outcome) compared to nonexposed individuals, propensity score matched for sex, age, race/ethnicity, and income (controls). The association between MetS components combinations and periodontal diseases was explored overall and across subgroups by sex and smoking. Periodontal health status prediction based on MetS components was assessed.

RESULTS

In total, 2258 individuals (n. 1129/group) with nested clinical-demographic features were analyzed. Exposure was associated with gingival bleeding (+ 18% risk for every unitary increase in MetS components, and triple risk when all five were combined), but not with stable periodontitis; the association was specific for women, but not for men, irrespective of smoking. The only MetS feature with significant association in men was high BP with periodontitis. CRP levels significantly increased from health to disease only among exposed women. MetS components did not substantially improve the prediction of bleeding/non-bleeding periodontal disease.

CONCLUSION

The observed women-specific association of gingival bleeding with single and combined MetS components advances gender and precision periodontology. Further research is needed to validate and expand these findings.

High-fat diet-induced metabolic syndrome increases ligature-induced alveolar bone loss in mice

BACKGROUND

It has been well documented that metabolic syndrome (MetS) increases severity of periodontitis. In this study, we determined the effect of high-fat diet (HFD)-induced MetS on alveolar bone loss in a mouse model with ligature-induced periodontitis. To understand how MetS increases bone loss, we tested our hypothesis that palmitic acid (PA), a most abundant saturated fatty acid in the HFD, interacts with lipopolysaccharide (LPS) to promote osteoclastogenesis.

METHODS

We induced MetS by feeding mice HFD for 18 weeks and induced periodontitis with ligature placement. After treatments, we assessed alveolar bone loss using micro-computed tomography and determined osteoclastogenesis using tartrate-resistant acid phosphatase (TRAP) staining. To explore the mechanisms, we treated macrophages with PA, LPS or both and analyzed the osteoclast formation and cytokine expression in macrophages.

RESULTS

While ligature robustly induced periodontitis in mice with or without MetS, the mice with MetS had more bone loss than those without MetS. PA and LPS cooperatively induced osteoclast formation and stimulated the expression of inflammatory cytokines involved in osteoclastogenesis potentially via a FAT/CD36-dependent mechanism in macrophages.

CONCLUSIONS

HFD-induced MetS increases alveolar bone loss in mice with ligature-induced periodontitis, and PA and LPS cooperatively stimulate osteoclast formation and proinflammatory gene expression in macrophages.

Association of Adiposity with Periodontitis and Metabolic Syndrome: From the Third National Health and Nutrition Examination Survey of United States

This study explored the epidemiological role of central adiposity and body mass index (BMI) in terms of clinical attachment loss (CAL)/pocket depth (PD) and metabolic syndrome components. This study included data from the National Health and Nutrition Examination Survey III of America on 12,254 adults aged 20 years of age or older with a blood sample, anthropometric measurements, and a periodontal examination. Clinical periodontitis measurements, including CAL and PD, were classified into quintiles or quartiles and compared. CAL was positively associated with central adiposity, hypertension, and hyperglycemia; the relationship between CAL and diabetes was stronger when central adiposity was absent (odds ratio [OR] and 95% confidence interval: 6.33, 2.14-18.72 vs. 3.14, 1.78-5.56). The relationship between CAL and impaired fasting glucose (IFG) differed slightly with BMI. The IFG ORs for normal, overweight, and obese patients were 1.63 (1.08-2.45), 1.76 (1.05-2.97), and 1.43 (0.88-2.30), respectively. CAL was positively correlated with all metabolic syndrome components except hypertriglyceridemia. Associations between CAL, diabetes, and IFG significantly varied with BMI. Periodontitis in individuals without central obesity or with normal bodyweight may independently indicate diabetes and IFG. Therefore, preventive measures against periodontitis without obesity are necessary to improve general and oral health.

Association of self-rated chewing function and oral health status with metabolic syndrome

PURPOSE

The study aimed to examine the association of self-rated chewing function, the number of teeth and periodontal status with metabolic syndrome.

METHODS

The participants were 11,119 adults aged 40-74 years who underwent specific health checkups, including an oral health examination, in 2018 in Japan. This study used the standard questions of the specific health checkups to obtain information on self-rated chewing function. A multinomial logistic regression analysis was performed with metabolic syndrome status as the dependent variable, and age, sex, lifestyle questions, self-rated chewing function, number of teeth, and periodontal status as the independent variables.

RESULTS

Number of teeth and periodontal status were significantly associated with metabolic syndrome after adjusting for confounding variables. Self-rated chewing function was significantly associated with metabolic syndrome in the crude analysis, but not after adjustment for confounding variables. Both number of teeth and periodontal status were significantly associated with self-rated chewing function.

CONCLUSION

There was no significant direct association between self-rated chewing function and metabolic syndrome. Self-rated chewing function may be an indicator of poor oral condition that links to metabolic syndrome.

Exploring the Mechanisms and Association between Oral Microflora and Systemic Diseases

The scope of dentistry is ever-changing and dynamic in all fields of dentistry including periodontal health and disease. Recent studies show that oral health and systemic health are interdependent, particularly in the way that poor oral hygiene and periodontal health affect the systemic health of an individual and vice versa. Periodontal diseases are multifactorial in nature in which the role of bacterial infections is inevitable. Furthermore, high-throughput sequencing technologies have shed light on the dysregulation of the growth of oral microbial flora and their environment, including those that are associated with periodontitis and other oral and non-oral diseases. Under such circumstances, it becomes important to explore oral microbiota and understand the effects of periodontal pathogens in the pathogenesis of systemic diseases. In addition, it may strengthen our view that a better understanding of oral microbial flora and proper examination of the oral cavity may aid in the early diagnosis and possible treatment of systemic diseases and conditions. This will eventually lead to providing better care to our patients. Therefore, in this research, we attempt to outline the periodontal pathophysiology along with the role of periodontal pathogens in some commonly encountered systemic conditions.

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.

Examining the association between serum IgG of oral bacteria and metabolic syndrome

Aim

This investigation explored the relationship between oral bacteria and metabolic syndrome (METS).

Materials and Methods

There were 4,882 subjects enrolled in this cross-sectional study from the NHANES III database. The severity of periodontitis was classified into mild, moderate and severe. We measured oral bacterial antibodies. We examined the relationship between serum immunoglobulin G (IgG) antibodies of oral bacteria and METS via performing multivariate regression analysis. Mediation analysis of oral bacteria on the correlation between periodontitis and METS was also executed.

Results

After adjusting for covariates, the serum IgG antibodies of P. nigrescens, E. corrodens, and E. nodatum were associated with the presence of METS (p = 0.006, p = 0.014 and p = 0.018, respectively). Furthermore, serum IgG antibodies of P. intermedia, T. forsythia and V. parvula were positively associated with the presence of METS (p = 0.001, p = 0.011, and p = 0.002, respectively) and ≥4 features of METS (p = 0.019, p = 0.025, and p = 0.02, respectively). P. intermedia IgG mediated 11.2% of the relationship between periodontitis and METS.

Conclusion

Serological markers of oral pathogens were correlated with the presence and the number of METS features after multivariable adjustment. Oral bacteria acted as a mediator of the correlation between periodontitis and METS. Our study provided a biologically plausible explanation for the association between periodontitis and METS, which provides a comprehensive evaluation of periodontitis.

Relationship between periodontal status and dyslipidemia in patients with type 2 diabetic nephropathy and chronic periodontitis: A cross-sectional study

OBJECTIVE

The aim of this study was to investigate the association between periodontitis and total serum cholesterol level in patients with type 2 diabetic nephropathy (T2DN).

BACKGROUND

Periodontitis is now recognized as the sixth complication of diabetes and can also affect other complications of diabetes, including nephropathy and coronary artery diseases. Studies have considered dyslipidemia as a risk factor for exacerbation of periodontitis.

METHODS

A total of 119 T2DN patients with chronic periodontitis were included in this observational study. Participants were stratified into the Normal (serum total cholesterol <5.17 mmol/L, n = 89) and the Dyslipidemia groups (serum total cholesterol ≥5.17 mmol/L, n = 30). Participants completed a validated questionnaire that collected information on oral hygiene behaviors and knowledge of oral health and underwent a clinical oral examination. The number of remaining teeth, probing depth (PD), clinical attachment level (CAL), and bleeding index (BI) was recorded. Physical examination and laboratory tests (fasting plasma glucose, serum glycosylated hemoglobin (HbA1c), total cholesterol, high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), triglyceride, and high-sensitivity C-reactive protein levels) were performed.

RESULTS

Means of CAL and BI were significantly higher in the Dyslipidemia group compared with the Normal group. In the Dyslipidemia group, PD and percent of sites with PD ≥4 mm were positively correlated with urinary albumin/creatinine ratios; PD and percent of sites with PD ≥4 and PD ≥5 mm were positively correlated with HbA1c level; a number of remaining teeth were negatively correlated with serum LDL-C level. After adjusting for age, gender, body mass index, smoking, FPG, and serum HbA1c and triglyceride levels, BI was found to be positively associated with dyslipidemia in T2DN patients with periodontitis.

CONCLUSION

T2DN patients with chronic periodontitis had a 2.355-fold higher risk of developing dyslipidemia, implying an important relationship between periodontitis and blood lipid control among T2DN patients.

Metabolic syndrome and periodontitis among adults: The 2018 Indonesia National Health Survey

Aim

This study aimed to examine the association between metabolic syndrome (MetS), its components, and periodontitis among Indonesian adults.

Materials and Methods

Cross‐sectional data from the 2018 Indonesia National Health Survey (Riskesdas) was analysed. The sample included dentate individuals aged 35 years or older for whom complete information was available on components of MetS and periodontitis, including bleeding on probing (BOP) (N = 13,356), pocket depth (PD) (N = 13,273), and clinical attachment loss (CAL) (N = 13,000). Rate ratios (RRs) and 95% confidence intervals (CIs) were estimated with negative binomial regression models.

Results

The prevalence of MetS was 41.0%. The prevalence of individuals having at least one tooth with BOP, one tooth with PD ≥4 mm, or one sextant with CAL ≥4 mm was 74.9%, 40.7%, and 40.6%, respectively. No associations were observed between MetS and BOP, PD, or CAL, but hyperglycaemia was constantly positively associated with BOP (RR = 1.06; 95% CI 1.01–1.11), PD (RR = 1.13; 95% CI 1.03–1.23), and CAL (RR = 1.15; 95% CI 1.08–1.23).

Conclusions

Our findings support the potential influence of hyperglycaemia on periodontitis. Incorporating oral disease prevention strategies into the management of systemic diseases could be beneficial for reducing the burden of these diseases in Indonesia.

Systems Biology in Periodontitis

Systems biology is a promising scientific discipline that allows an integrated investigation of host factors, microbial composition, biomarkers, immune response and inflammatory mediators in many conditions such as chronic diseases, cancer, neurological disorders, and periodontitis. This concept utilizes genetic decoding, bioinformatic, flux-balance analysis in a comprehensive approach. The aim of this review is to better understand the current literature on systems biology and identify a clear applicability of it to periodontitis. We will mostly focus on the association between this condition and topics such as genomics, transcriptomics, proteomics, metabolomics, as well as contextualize delivery systems for periodontitis treatment, biomarker detection in oral fluids and associated systemic conditions.

Association between Healthy Lifestyle (Diet Quality, Physical Activity, Normal Body Weight) and Periodontal Diseases in Korean Adults

This study aimed to investigate the association between healthy lifestyle (HLS; i.e., diet quality, physical activity, normal weight) and periodontal diseases in Korean adults. Studying this association may help inform future intervention programs aimed at preventing the development of periodontal diseases. Raw data of the Korea National Health and Nutrition Examination Survey (KNHANES) VII (2016–2018) were used. Data from 12,689 adults aged 19 years and over who had a periodontal examination were analyzed. The associations between HLS and periodontal diseases were analyzed using multivariate logistic regression after adjusting for demographic and health factors as covariates. We found that each of the HLS (diet quality, physical activity, normal body weight) practices was significantly associated with periodontal diseases (OR: 1.32, 95% CI: 1.13–1.55; OR: 1.16, 95% CI: 1.04–1.30; OR: 1.26, 95% CI: 1.14–1.40, respectively). In particular, having poor HLS practices was identified as a risk factor for periodontal diseases (OR: 1.54, 95% CI: 1.10–2.15). HLS was associated with periodontal diseases. Thus, in addition to improving oral hygiene—the primary focus in the past—improving HLS should be emphasized for patients with periodontal diseases.

Inhibition of acid sphingomyelinase by imipramine abolishes the synergy between metabolic syndrome and periodontitis on alveolar bone loss

BACKGROUND AND OBJECTIVE

Clinical studies have shown that metabolic syndrome (MetS) exacerbates periodontitis. However, the underlying mechanisms remain largely unknown. Since our animal study has shown that high-fat diet-induced MetS exacerbates lipopolysaccharide (LPS)-stimulated periodontitis in mouse model and our in vitro study showed that acid sphingomyelinase (aSMase) plays a key role in the amplification of LPS-triggered pro-inflammatory response by palmitic acid (PA) in macrophages, we tested our hypothesis that inhibitor of aSMase attenuates MetS-exacerbated periodontitis in animal model. Furthermore, to explore the potential underlying mechanisms, we tested our hypothesis that aSMase inhibitor downregulates pro-inflammatory and pro-osteoclastogenic gene expression in macrophages in vitro.

MATERIAL AND METHODS

We induced MetS and periodontitis in C57BL/6 mice by feeding high-fat diet (HFD) and periodontal injection of A. actinomycetemcomitans LPS, respectively, and treated mice with imipramine, a well-established inhibitor of aSMase. Micro-computed tomography (micro-CT), tartrate-resistant acid phosphatase staining, histological and pathological evaluations as well as cell cultures were performed to evaluate alveolar bone loss, osteoclast formation, periodontal inflammation and pro-inflammatory gene expression.

RESULTS

Analysis of metabolic parameter showed that while HFD induced MetS by increasing bodyweight, insulin resistance, cholesterol and free fatty acids, imipramine reduced free fatty acids but had no significant effects on other metabolic parameters. MicroCT showed that either MetS or periodontitis significantly reduced bone volume fraction (BVF) of maxilla and the combination of MetS and periodontitis further reduced BVF. However, imipramine increased BVF in mice with both MetS and periodontitis to a level similar to that in mice with periodontitis alone, suggesting that imipramine abolished the synergy between MetS and periodontitis on alveolar bone loss. Consistently, results showed that imipramine inhibited osteoclast formation and periodontal inflammation in mice with both MetS and periodontitis. To elucidate the mechanisms by which imipramine attenuates MetS-exacerbated periodontitis, we showed that imipramine inhibited the upregulation of pro-inflammatory cytokines and transcription factor c-FOS as well as ceramide production by LPS plus PA in macrophages.

CONCLUSION

This study has shown that imipramine as an inhibitor of aSMase abolishes the synergy between MetS and periodontitis on alveolar bone loss in animal model and inhibits pro-inflammatory and pro-osteoclastogenic gene expression in macrophages in vitro. This study provides the first evidence that aSMase is a potential therapeutic target for MetS-exacerbated periodontitis.

Association between periodontitis and the metabolic syndrome in the Hamburg City Health Study

BACKGROUND

Previous studies demonstrated an association between severe chronic periodontitis (CP) and the metabolic syndrome (MetS). However, these studies mostly employed the meanwhile outdated NCEP-ATPIII case definition of the MetS. Additionally, CP was rarely diagnosed based on a full-mouth examination. Thus, the aim of the current study was to re-evaluate the potential association between CP and the MetS in the Hamburg City Health Study (HCHS), a large population-based survey of middle-aged and elderly men and women in Germany, in view of more current definitions of the MetS and CP.

METHODS

A cross-sectional study was performed with baseline-data from participants of the Hamburg City Health Study (HCHS). Periodontitis severity grades were determined in a random sample of 6,209 participants of which 5,456 had sufficient data to call absence or presence of the MetS. Variables defining the MetS according to the currently valid harmonized definition were determined and a full-mouth examination was performed, including determination of the clinical attachment loss (AL), bleeding on probing (BOP), and dental plaque (PI) index. CP was classified in three grades of severity (none/mild, moderate, and severe). The Kruskal-Wallis test or the Chi-squared test were used for descriptive statistics and multivariate logistic regression models with and without adjustments for potential confounders (age, sex, smoking, high sensitivity C-reactive protein (hsCRP), energy intake, and physical activity) were used to test for associations.

RESULTS

The prevalence of the MetS (39.0%) increased according to the severity grades of periodontitis (none/mild: 33.6%; moderate: 38.7%, and severe: 46.8%). Multivariate logistic regression analyses demonstrated that severe but not moderate CP was associated with the MetS after adjusting for age and sex (odds ratio [OR]: 1.24; 95% confidence interval [CI]: 1.03-1.48; p = 0.02). However, the association was attenuated after additional adjustment for smoking (OR: 1.19; 95% CI: 0.99-1.43; p = 0.058) and hsCRP, energy intake, and physical activity (OR: 1.11; 95% CI 0.91-1.36; p = 0.294).

CONCLUSIONS

The use of the more current definitions for the MetS and CP confirmed previous observations of an age- and sex-adjusted association between severe CP and the MetS. Smoking, high energy intake and low physical activity were identified as important lifestyle-related confounders. Abdominal obesity, as indicated by elevated waist circumference, came out as the most important component of the MetS in relation to CP. This article is protected by copyright. All rights reserved.

Association of hyperglycaemia and periodontitis: an updated systematic review and meta-analysis

Purpose

The aim of this updated systematic review and meta-analysis was the association between hyperglycemia and periodontitis.

Methods

We searched PubMed/MEDLINE, Web of Science, and Scopus until March 2021. The key search words were based on "periodontitis" and "hyperglycemia." We included cohort, case-control, and cross-sectional studies, restricted to publications in English. The quality assessment of included studies and data extraction were done by two independent reviewers. Meta-analysis was performed for cross-sectional studies using the random-effects model.

Results

The literature search yielded 340 studies, and finally, 19 and 11 studies were included in systematic review and meta-analysis, respectively. The total sample size of the eligible studies in the meta-analysis was 38,896 participants, of whom 33% were male with a mean age of 51.20 ± 14.0 years. According to a random-effect meta-analysis in cross-sectional studies, the pooled odds ratio (OR) for the association between hyperglycemia and periodontal indices was statistically significant (OR: 1.50, 95%CI: 1.11, 1.90). There was evidence of publication bias (coefficient: - 3.53, p-value = 0.014) which, after imputing missing studies, the pooled OR of the association between hyperglycemia and periodontitis change to 1.55 (95%CI: 1.20, 1.90).

Conclusion

Results of the present study show that hyperglycemia was positively associated with periodontitis. However, more cohort and prospective longitudinal studies should be conducted to find the exact association. Overall, it seems the management of hyperglycemia could be considered as a preventive strategy for periodontitis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-021-00861-9.

State of Evidence on Oral Health Problems in Diabetic Patients: A Critical Review of the Literature

Diabetes mellitus (DM) is a global health problem, having recognized that in the next 20 years the number of diabetic patients in the world will increase to 642 million. DM exerts enormous repercussions on general health diabetic (especially derived from vascular, cardiac, renal, ocular, or neurological affectation). It entails in addition a high number of deaths directly related to the disease, as well as a high health care cost, estimated at $673 billion annually. Oral cavity is found among all the organs and systems affected in the course of DM. Important pathologies are developed with higher prevalence, such as periodontitis (PD), alterations in salivary flow, fungal infections, oral cancer, and oral potentially malignant disorders (OPMD). It has been proven that PD hinders the metabolic control of DM and that the presence of PD increases the possibility for developing diabetes. Despite the relevance of these oral pathologies, the knowledge of primary care physicians and diabetes specialists about the importance of oral health in diabetics, as well as the knowledge of dentists about the importance of DM for oral health of patients is scarce or non-existent. It is accepted that the correct management of diabetic patients requires interdisciplinary teams, including dentists. In this critical review, the existing knowledge and evidence-degree on the preventive, clinical, diagnosis, prognosis, and therapeutic aspects of oral diseases that occur with a significant frequency in the diabetic population are developed in extension.

State of Evidence on Oral Health Problems in Diabetic Patients: A Critical Review of the Literature

Diabetes mellitus (DM) is a global health problem, having recognized that in the next 20 years the number of diabetic patients in the world will increase to 642 million. DM exerts enormous repercussions on general health diabetic (especially derived from vascular, cardiac, renal, ocular, or neurological affectation). It entails in addition a high number of deaths directly related to the disease, as well as a high health care cost, estimated at $673 billion annually. Oral cavity is found among all the organs and systems affected in the course of DM. Important pathologies are developed with higher prevalence, such as periodontitis (PD), alterations in salivary flow, fungal infections, oral cancer, and oral potentially malignant disorders (OPMD). It has been proven that PD hinders the metabolic control of DM and that the presence of PD increases the possibility for developing diabetes. Despite the relevance of these oral pathologies, the knowledge of primary care physicians and diabetes specialists about the importance of oral health in diabetics, as well as the knowledge of dentists about the importance of DM for oral health of patients is scarce or non-existent. It is accepted that the correct management of diabetic patients requires interdisciplinary teams, including dentists. In this critical review, the existing knowledge and evidence-degree on the preventive, clinical, diagnosis, prognosis, and therapeutic aspects of oral diseases that occur with a significant frequency in the diabetic population are developed in extension.

State of Evidence on Oral Health Problems in Diabetic Patients: A Critical Review of the Literature

Diabetes mellitus (DM) is a global health problem, having recognized that in the next 20 years the number of diabetic patients in the world will increase to 642 million. DM exerts enormous repercussions on general health diabetic (especially derived from vascular, cardiac, renal, ocular, or neurological affectation). It entails in addition a high number of deaths directly related to the disease, as well as a high health care cost, estimated at $673 billion annually. Oral cavity is found among all the organs and systems affected in the course of DM. Important pathologies are developed with higher prevalence, such as periodontitis (PD), alterations in salivary flow, fungal infections, oral cancer, and oral potentially malignant disorders (OPMD). It has been proven that PD hinders the metabolic control of DM and that the presence of PD increases the possibility for developing diabetes. Despite the relevance of these oral pathologies, the knowledge of primary care physicians and diabetes specialists about the importance of oral health in diabetics, as well as the knowledge of dentists about the importance of DM for oral health of patients is scarce or non-existent. It is accepted that the correct management of diabetic patients requires interdisciplinary teams, including dentists. In this critical review, the existing knowledge and evidence-degree on the preventive, clinical, diagnosis, prognosis, and therapeutic aspects of oral diseases that occur with a significant frequency in the diabetic population are developed in extension.

Periodontitis and diabetes mellitus co-morbidity: A molecular dialogue

BACKGROUND

Type 2 diabetes mellitus (T2DM) and periodontitis are two biologically linked diseases that often coexist in complex interaction. While periodontitis may lead to insulin receptor desensitization, diabetes may increase the expression of inflammatory cytokines, such as Tumor Necrosis Factor-α (TNF-α) and Interleukin 6 (IL-6), in the gingival crevicular fluid and activate osteoclasts via Receptor activator of nuclear factor kappa-Β ligand (RANK-L) production, leading to bone resorption. However, the association between the two diseases processes, where one may exacerbate the progression of the other, is unclear. In addition, both diseases have similar mechanistic themes, such as chronic inflammation and oxidative stress. This review aimed to investigate the pathophysiological and molecular mechanisms underlying T2DM and periodontitis.

HIGHLIGHT

Uncontrolled diabetes is often associated with severe periodontitis, measured by clinical attachment loss. Alteration in the oral microbiome composition, which may activate the host inflammatory response and lead to irreversible oxidative stress, is a common finding in both diseases. An understanding of the molecular crosstalk between the two disease processes is crucial for developing therapeutic targets that inhibit bone resorption and halt the progression of periodontitis in patients with diabetes.

CONCLUSION

The Oral microbiome composition in T2DM and periodontitis shifts toward dysbiosis, favoring bacterial pathogens, such as Fusobacteria and Porphyromonas species. Both conditions are marked by pro-inflammatory immune activity via the activation of Interleukin 17 (IL-17), Interleukin 1 (IL-1), TNF-α, and Nuclear Factor Kappa Beta (NF-κB). Common molecular crosstalk signaling appears to involve advanced glycation end products (AGEs) and oxidative stress. Thus, future drug targets are multifactorial, ranging from modulatory of host inflammatory response to preventing the accumulation of AGEs and oxidative free radicals.

Waistline to the gumline: Relationship between obesity and periodontal disease-biological and management considerations

Obesity is a pandemic and periodontitis is the sixth most prevalent disease in the world. These two noncommunicable diseases share several risk determinants. Epidemiologic evidence from the last 2 decades has established an increase in periodontitis prevalence in obese and overweight individuals. Biologic mechanisms potentially linking obesity and periodontal disease are adiposity-associated hyperinflammation, microbial dysbiosis, altered immune response, specific genetic polymorphisms, and increased stress. However, because of the lack of longitudinal interventional studies and randomized clinical trials, there is insufficient evidence to determine the cause-effect relationship between these two diseases. Despite this, the negative impact of obesity on oral health is well established. Several logistic and physiologic complications are associated with treating obese patients in a dental setting, and it requires an interprofessional team approach. Oral health care professionals need to be aware of the specific management considerations while rendering for this cohort, including modified practice facility and equipment, tailored supportive periodontal therapy, and heightened precaution during conscious sedation and surgical procedures.

Untargeted and targeted gingival metabolome in rodents reveal metabolic links between high-fat diet-induced obesity and periodontitis

AIM

To characterize gingival metabolome in high-fat diet (HFD)-induced obesity in mice with/without periodontitis.

METHODS

HFD-induced obesity mouse model was established by 16-week feeding, and a lean control group was fed with low-fat diet (n = 21/group). Both models were induced for periodontitis on the left sides by molar ligation for 10 days, whereas the right sides were used as controls. Gingival metabolome and arginine metabolism were analysed by non-targeted/targeted liquid chromatography-mass spectrometry.

RESULTS

Of 2247 reference features, presence of periodontitis altered 165 in lean versus 885 in HFD mice; and HFD altered 525 in absence versus 1435 in presence of periodontitis. Compared with healthy condition, periodontitis and HFD had distinct effects on gingival metabolome. Metabolomic impacts of periodontitis were generally greater in HFD mice versus lean controls. K-medoids clustering showed that HFD amplified the impacts of periodontitis on gingival metabolome in both intensity and extensity. Ten metabolic pathways were enriched, including 2 specific to periodontitis, 5 specific to HFD and 3 shared ones. Targeted validation on arginine metabolism confirmed the additive effects between HFD and periodontitis.

CONCLUSION

The obese population consuming excessive HFD display amplified metabolic response to periodontitis, presenting a metabolic susceptibility to exacerbated periodontal destruction.

Accuracy of a salivary examination kit for the screening of periodontal disease in a group medical check-up (Japanese-specific health check-up)

The purpose of the present study was to investigate the accuracy of a screening method using salivary tests to screen for periodontal disease.In total, 1888 individuals older than 30 years in 2017 and 2296 in 2018 who underwent medical check-ups for metabolic syndrome agreed to participate and simultaneously underwent a dental examination by dentists and salivary tests. Salivary occult blood, protein, and ammonia levels and white blood cell counts were evaluated in salivary tests using commercially available kits. The relationship between the results of the salivary tests and dental examination was examined and classification performance was analyzed.The prevalence of periodontal disease was 69.9% in 2017 and 66.8% in 2018. Salivary ammonia showed the highest classification performance in both years (sensitivity 83.5 and 83.1%, precision 73.0 and 69.3%, F-measure 0.779 and 0.756). Occult blood, which was assessed using a monoclonal antibody to human hemoglobin, also showed good performance (sensitivity 69.5%, precision 70.6%, F-measure 0.701). Questions regarding self-reported gingival bleeding were not sufficient to screen for periodontitis. The present results suggest that screening tests using salivary samples may detect periodontal disease in approximately 70% to 80% of subjects in a large population.Conclusion: Salivary ammonia and hemoglobin have potential as salivary markers in the screening of periodontal disease.

Effect of dental intervention on improvements in metabolic syndrome patients: a randomized controlled clinical trial

Background

Metabolic syndrome (MetS), caused by the accumulation of visceral fat, is considered a major cause of cardiovascular disease. This randomized controlled trial aimed to clarify the effect of dental intervention, including prosthodontics and/or periodontal treatment, combined with dietary and exercise guidance on MetS.

Methods

In total, 112 patients who met the Japanese waist circumference criteria of MetS were recruited. The intervention group (ITG) received dental intervention along with dietary and exercise guidance, while the control group (CTG) received dietary and exercise guidance alone. Three outcome measurements were obtained before intervention (BL), 1 month after intervention (1M), and 3 months after intervention (3M).

Results

Body water rate (p = 0.043) was significantly higher in ITG than in CTG at 1M. Simultaneously, fasting blood sugar level (p = 0.098) tended to be lower in ITG than in CTG. Lean mass (p = 0.037) and muscle mass (p = 0.035) were significantly higher and body weight (p = 0.044) significantly lower in ITG than in CTG at 3M. Body mass index (p = 0.052) tended to be lower in ITG than in CTG.

Conclusions

Dental intervention combined with lifestyle guidance may improve anthropometric status and reduce the risk of MetS.

Trial registration

University Hospital Medical Information Network Center Unique UMIN000022753. https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000026176.

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.

Association between periodontitis and hyperlipidaemia: A systematic review and meta-analysis

To date, it has been reported that periodontitis (PD) may be associated with hyperlipidaemia in clinical practice. However, data on this issue are inconsistent and controversial. The purpose of this meta-analysis was to identify the association between PD and hyperlipidaemia. Here, 21 case-control and eight cross-sectional studies on PD and hyperlipidaemia were included in the random-effects meta-analysis, involving 2060 patients with PD and 2776 healthy controls (HC). Meta-analysis showed that serum triglyceride (TG) and total cholesterol (TC) levels in the PD group were significantly higher than those in the HC group [TG, weighted mean difference (WMD) = 19.4 mg/dL, 95% confidence interval (CI) 13.3-25.5 mg/dL, P = .000; TC, WMD = 15.4 mg/dL, 95%CI 10.2-20.6 mg/dL, P = .000]. Subgroup analysis stratified by study design validated that PD was associated with higher serum TG and TC levels. In addition, compared with the HC group, serum low-density lipoprotein (LDL) in patients with PD showed a markedly higher level (WMD = 11.7 mg/dL, 95% CI 8.3-15.0 mg/dL, P = .000), whereas serum high-density lipoprotein (HDL) in PD group exhibited a significantly lower level (WMD = -4.5 mg/dL, 95%CI -6.4 - -2.7 mg/dL, P = .000). Finally, no significant publication bias was observed and sensitivity analysis also confirmed the stability of our meta-analyses. In conclusion, the accumulated evidence suggests that PD is indeed associated with hyperlipidaemia in humans. More interventions for lowering lipids or increasing HDL may benefit the patients with PD, which need be further investigated in prospective clinical trials.

Periodontitis is an inflammatory disease of oxidative stress: We should treat it that way

Periodontitis is a highly prevalent disease. As it progresses, it causes serious morbidity in the form of periodontal abscesses and tooth loss and, in the latter stages, pain. It is also now known that periodontitis is strongly associated with several nonoral diseases. Thus, patients with periodontitis are at greater risk for the development and/or exacerbation of diabetes, chronic obstructive pulmonary disease, and cardiovascular diseases, among other conditions. Although it is without question that specific groups of oral bacteria which populate dental plaque play a causative role in the development of periodontitis, it is now thought that once this disease has been triggered, other factors play an equal, and possibly more important, role in its progression, particularly in severe cases or in cases that prove difficult to treat. In this regard, we allude to the host response, specifically the notion that the host, once infected with oral periodontal pathogenic bacteria, will mount a defense response mediated largely through the innate immune system. The most abundant cell type of the innate immune system - polymorphonuclear neutrophils - can, when protecting the host from microbial invasion, mount a response that includes upregulation of proinflammatory cytokines, matrix metalloproteinases, and reactive oxygen species, all of which then contribute to the tissue damage and loss of teeth commonly associated with periodontitis. Of the mechanisms referred to here, we suggest that upregulation of reactive oxygen species might play one of the most important roles in the establishment and progression of periodontitis (as well as in other diseases of inflammation) through the development of oxidative stress. In this overview, we discuss both innate and epigenetic factors (eg, diabetes, smoking) that lead to the development of oxidative stress. This oxidative stress then provides an environment conducive to the destructive processes observed in periodontitis. Therefore, we shall describe some of the fundamental characteristics of oxidative stress and its effects on the periodontium, discuss the diseases and other factors that cause oxidative stress, and, finally, review potentially novel therapeutic approaches for the management (and possibly even the reversal) of periodontitis, which rely on the use of therapies, such as resveratrol and other antioxidants, that provide increased antioxidant activity in the host.

The association of periodontal diseases with metabolic syndrome and obesity

Periodontitis is a multifactorial chronic inflammatory disease associated with dysbiotic plaque biofilms and characterized by progressive destruction of the tooth-supporting apparatus. Globally, it is estimated that 740 million people are affected by its severe form. Periodontitis has been suggested to be linked to obesity and metabolic syndrome. Obesity, defined as excessive fat accumulation, is a complex multifactorial chronic inflammatory disease, with a high and increasing prevalence. Metabolic syndrome is defined as a cluster of obesity, dyslipidemia, hypertension, and dysglycemia. Obesity, metabolic syndrome and periodontitis are among the most common non-communicable diseases and a large body of evidence from epidemiologic studies supports the association between these conditions. Extensive research has established plausible mechanisms to explain how these conditions can negatively impact each other, pointing to a bidirectional adverse relationship. At present there is only limited evidence available from a few intervention studies. Nevertheless, the global burden of periodontitis combined with the obesity epidemic has important clinical and public health implications for the dental team. In accordance with the common risk factor approach for tackling non-communicable diseases, it has been proposed that oral healthcare professionals have an important role in the promotion of periodontal health and general well-being through facilitation of healthy lifestyle behaviours.

Role of Cluster of Differentiation 163 in Diabetes-Periodontitis Interplay

Background

The aim of the present study was to assess and quantify cluster of differentiation 163 (CD163) protein levels and CD163 messenger RNA (mRNA) gene expression in subgingival plaque samples of generalized chronic periodontitis subjects with and without type II diabetes mellitus (DM).

Materials and methods

Eighty chronic periodontitis subjects were selected and divided into 40 systemically healthy, generalized chronic periodontitis subjects (Group I) and 40 generalized chronic periodontitis subjects diagnosed with type II diabetes mellitus (Group II). Age, body mass index (BMI), income, plaque index (PI), bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL) were recorded. CD163 protein and gene expressions were quantified and compared between the groups.

Results 

The mean age, BMI, income, PI, BOP %, and CD163 protein and gene expression were higher in Group II (p< 0.05) as compared to Group I. In Group I, CD163 protein levels showed a negative correlation with respect to BMI and PI, and this was statistically significant. In Group II, all the periodontal parameters showed a positive correlation with CD163 protein levels. Overall, PI and BOP % were significantly correlated with CD163 protein levels. Both CD163 protein and gene expression showed a negative correlation with each other (p= 0.001).

Conclusion

The elevated protein levels of CD163 in the subgingival plaque samples of generalized chronic periodontitis individuals with type II diabetes mellitus signify the involvement of CD163 in the pathogenesis of both periodontitis and diabetes mellitus. CD163 can play a challenging role as a diagnostic, as well as a prognostic biomarker, in both these inflammatory diseases.

6-Shogaol, an active ingredient of ginger, inhibits osteoclastogenesis and alveolar bone resorption in ligature-induced periodontitis in mice

BACKGROUND

Periodontitis is an inflammatory disease of the tissues surrounding teeth that causes destruction of connective tissues. During the progress of periodontitis, osteoclasts are solely accountable for the resorption of alveolar bones that leads to the loss of teeth if not properly treated. Thus, the development of effective anti-resorptive therapies will greatly benefit the treatment of periodontitis patients. In the present study, we suggest an inhibitory effect of 6-shogaol, an ingredient of ginger, on osteoclast differentiation and bone resorption.

METHODS

Mouse bone marrow cells were cultured in the presence of macrophage-colony stimulating factor and receptor activator of nuclear factor-κB ligand (RANKL) to investigate the effect of 6-shogaol on osteoclast differentiation and intracellular signaling pathways. 6-shogaol significantly reduced osteoclast differentiation, actin ring formation, and resorption. In the presence of 6-shogaol, osteoclast signaling including the RANKL-induced activation of mitogen-activated protein kinases, Ca2+ oscillation, generation of reactive oxygen species, and nuclear factor of activated T-cells, cytoplasmic 1 nuclear translocation was significantly inhibited in vitro. Furthermore, a ligature-induced periodontitis model in mice was used to determine the role of 6-shogaol in vivo.

RESULTS

The administration of 6-shogaol prevented osteoclastogenesis and alveolar bone resorption induced by ligature. Furthermore, the ligature-induced number of macrophages and neutrophils as well as the expression of interleukin-1β and tumor necrosis factor-α were considerably lower in the periodontal tissues following shogaol injection.

CONCLUSION

These results confirm the anti-osteoclastogenic effect of 6-shogaol and suggest the possibility of application as an anti-resorptive strategy in periodontitis.

Obesity and Periodontal Disease: A Narrative Review on Current Evidence and Putative Molecular Links

Background:

Obesity represents one of the main health problems worldwide and is considered a risk factor for several diseases, including periodontitis, which is a microbially-associated inflammatory disease affecting the tooth-supporting structures.

Objective:

The aim of this review was to report the current direct and indirect evidence concerning the possible association between obesity and periodontitis and their putative molecular links.

Methods:

A literature search was conducted between January 1999 and September 2019, in PubMed/MEDLINE and Science Direct databases, using pertinent keyword combined by Boolean operators. Through a multi-step screening process (literature search; articles title and abstract evaluation and full-text reading), studies fitting inclusion/exclusion criteria were considered for the review.

Results:

35 studies were included in the present review (17 observational studies; 7 systematic reviews; 11 systematic reviews with meta-analysis), focusing on the direct and indirect evidence of the possible association between obesity and periodontitis and their potential etiopathogenic molecular links

Conclusion:

Although the majority of the studies reported a positive association between obesity and periodontitis, the heterogeneity of the classification criteria and of the clinical parameters employed in the studies for both obesity and periodontitis evaluation, complicated the comparison of the results, thus considered inconclusive. Although several putative molecular pathogenic links between obesity and periodontitis have been highlighted, further studies, with longer follow-ups and with homogeneous clinical criteria, are needed to better understand the putative relation between obesity and periodontal disease.

Gingival crevicular fluid levels of visfatin in patients with chronic periodontitis and polycystic ovary syndrome

Objective

Recently, the association between periodontal diseases and polycystic ovary syndrome (PCOS) has been established, and it has been revealed that visfatin levels increase in chronic periodontitis (CP) and PCOS. However, there was no study comparing the mean visfatin levels between advanced CP and PCOS. Therefore, the probable role of visfatin linking these diseases remains unknown, and this study was conducted to address this gap.

Methods

In this age- and weight-matched case-control study (cases with PCOS disease and controls without it), 110 female participants were divided into 4 groups based on clinical findings. The 1st group participants had both PCOS and advanced CP (n=30), 2nd group participants had only PCOS (n=25), 3rd group participants had only advanced CP (n=23), and 4th group comprised of healthy participants (n=32). Enzyme-linked immunosorbent assay was used to investigate visfatin levels in the gingival crevicular fluid (GCF). Data were collected and analyzed using Stata software (version 11).

Results

The results revealed the significant effect of both PCOS and advanced CP on visfatin levels in the GCF (P<0.05).

Conclusion

According to the results of this study, the visfatin level in the GCF could be the probable link of association between PCOS and advanced CP.

A review of the influence of periodontal treatment in systemic diseases

The effects and consequences of periodontal diseases might not be confined to the oral cavity. A great body of evidence has arisen supporting the claim demonstrating an association with several systemic conditions and diseases. With different levels of evidence, an association between periodontal disease and cardiovascular disease, diabetes, psoriasis, rheumatoid arthritis, pregnancy outcomes and respiratory diseases has been established. However, the true nature of this association, if it is causal, still remains elusive. For a better understanding of the complex relationships linking different conditions, interventional studies now begin to focus on the possible outcomes of periodontal treatment in relation to the events, symptoms and biomarkers of several systemic disorders, assessing if periodontal treatment has any impact on them, hopefully reducing their severity or prevalence. Therefore, we proceeded to review the recent literature on the subject, attempting to present a brief explanation of the systemic condition or disease, what proposed mechanisms might give biological plausibility to its association with periodontal disease, and finally and more importantly, what data are currently available pertaining to the effects periodontal treatment may have. Raising awareness and discussing the possible benefits of periodontal treatment on overall systemic health is important, in order to change the perception that periodontal diseases are only limited to the oral cavity, and ultimately providing better and comprehensive care to patients.

Effect of non-surgical periodontal treatment on gingival crevicular fluid and serum leptin levels in periodontally healthy chronic periodontitis and chronic periodontitis patients with type 2 diabetes mellitus

AIM

The aim of the present study was to evaluate the effect of non-surgical periodontal therapy (NSPT) on gingival crevicular fluid (GCF) and serum leptin levels and glycemic status in periodontally healthy patients with chronic periodontitis (CP) with and without type 2 diabetes mellitus (T2DM).

METHODS

Ninety patients were divided into three groups: periodontally healthy (group 1), CP (group 2) and CP with T2DM (group 3). The groups were evaluated for clinical parameters of probing pocket depth (PPD), clinical attachment level (CAL), plaque index, gingival index, biochemical parameters of GCF, serum leptin levels, and glycemic status pre- and post-NSPT.

RESULTS

The baseline PPD and CAL for group 2 was 4.98 ± 0.49 mm and 5.35 ± 0.55 mm, respectively; for group 3 it was 5.60 ± 0.38 mm and 6.01 ± 0.38 mm, respectively. There was a considerable reduction in these parameters post-NSPT, with group 2 showing better resolution. Pretreatment serum leptin levels revealed increasing values from group 1 to group 3 and decreasing GCF values from group 3 to group 1, exhibiting an inverse relationship. Group 3 also showed an improvement in glycemic status post-NSPT.

CONCLUSION

NSPT was effective in improving clinical parameters, increasing GCF, reducing serum leptin levels, and also improving glycemic status in patients with CP and CP with T2DM.

Effect of non-surgical periodontal therapy on insulin resistance and insulin sensitivity among individuals with borderline diabetes: A randomized controlled trial

OBJECTIVE

To investigate the effect of non-surgical periodontal therapy on insulin resistance and sensitivity among individuals with borderline diabetes not receiving medications.

METHODS

A crossover, randomized controlled trial was conducted among participants with borderline diabetes diagnosed by a 75-g oral glucose tolerance test. Participants were randomly assigned to either an early or later intervention group. The early intervention group underwent non-surgical periodontal therapy of scaling and root planing during the first 6 months, followed by a 6-month non-intervention period. The order was reversed in the later intervention group. Primary outcomes included: fasting or post-load serum glucose and insulin, body mass index (BMI), HOMA-IR, HOMA-β, and Matsuda Index.

RESULTS

Seventy-four participants were randomized, and 71 participants completed the trial. There were no significant differences between groups in glucose and insulin concentrations during the intervention and non-intervention periods. When analyzed within groups by median-split of bleeding on probing (BOP) levels before intervention, the lower BOP group showed improved changes in BMI, HOMA-IR, HOMA-β, and Matsuda Index (P < 0.05). Further, we observed a positive correlation between baseline BOP and change in BMI (P = 0.06). Change in BMI was positively correlated with changes in HbA_1c, HOMA-IR, and HOMA-β (P < 0.05), and inversely correlated with change in Matsuda Index (P = 0.001).

CONCLUSIONS

Periodontal therapy had no significant effect on markers related to insulin and glucose metabolism among individuals with borderline diabetes. However, participants with a lower BOP (%) showed significant improvements in BMI, fasting serum insulin, HOMA-IR, HOMA-β and Matsuda Index.

CLINICAL SIGNIFICANCE

Among individuals diagnosed with borderline diabetes, those who had <37% of a lower BOP (%) showed potential improvements in BMI, fasting serum insulin, HOMA-IR, HOMA-β and Matsuda Index following non-surgical periodontal therapy.

Periodontal complications with obesity

The purpose of this paper was to identify and summarize current evidence describing periodontal complications associated with obesity. Electronic searches supplemented with manual searches were carried out to identify relevant systematic reviews. Identification, screening, eligibility, and inclusion of studies were performed independently by two reviewers. A MeaSurement Tool to Assess systematic Reviews (AMSTAR) was used to assess the quality and risk of bias of the included reviews. From 430 titles and abstracts screened, 14 systematic reviews were considered as eligible for inclusion in this meta-review. Eight reviews reported on cross-sectional studies investigating the association of obesity and periodontal diseases, 4 included longitudinal studies, 5 addressed response to periodontal therapy, 5 reported on studies investigating biomarkers, and only 2 were related to pediatric population samples. Systematic review summaries in the various study design domains (cross-sectional, longitudinal and experimental) report that obese individuals are more likely to have periodontal diseases, with more severe periodontal conditions, than nonobese individuals, with cross-sectional evidence congruent with longitudinal studies showing that obesity or weight gain increases the risk of periodontitis onset and progression. Published research on the effect of obesity on responses to periodontal therapy, or systemic or local biomarkers of inflammation, is variable and therefore inconclusive based on the evidence currently available, which suggests that overweight/obesity contributes to periodontal complications independently of other risk factors, such as age, gender, smoking, or ethnicity. This evidence supports the need for risk assessments for individual patients to facilitate personalized approaches in order to prevent and treat periodontal diseases.