Association between periodontal pathogens and systemic disease

Biomaterials with antifungal strategies to fight oral infections

Oral fungal infections pose a threat to human health and increase the economic burden of oral diseases by prolonging and complicating treatment. A cost-effective strategy is to try to prevent these infections from happening in the first place. With this purpose, biomaterials with antifungal properties are a crucial element to overcome fungal infections in the oral cavity. In this review, we go through different kinds of biomaterials and coatings that can be used to functionalize them. We also review their potential as a therapeutic approach in addition to prophylaxis, by going through traditional and alternative antifungal compounds, e.g., essential oils, that could be incorporated in them, to enhance their efficacy against fungal pathogens. We aim to highlight the potential of these technologies and propose questions that need to be addressed in prospective research. Finally, we intend to concatenate the key aspects and technologies on the use of biomaterials in oral health, to create an easy to find summary of the current state-of-the-art for researchers in the field.

Periodontal disease: A silent factor in the development and progression of diabetic retinopathy

The global increase in the prevalence of type 2 diabetes mellitus (T2DM) and its complications presents significant challenges to public health. Recently, per-iodontal disease (PD) was recognized as a factor that is likely to influence the progression of T2DM and its complications due to its potential to exacerbate systemic inflammation and oxidative stress. In this editorial, we comment on the article published by Thazhe Poyil et al in the very recent issue of the World Journal of Diabetes in 2024, which investigated the correlation between PD and diabetic retinopathy (DR) in T2DM patients, with emphasis on the association between periodontal swollen surface area, glycated hemoglobin (HbA1c), interleukin-6 (IL-6), and lipoprotein (a). The findings by Thazhe Poyil et al are significant as they demonstrate a strong link between PD and DR in T2DM patients. This correlation highlights the importance of addressing periodontal health in diabetes management to potentially reduce the risk and severity of DR, a complication of diabetes. The integration of periodontal evaluation and treatment into diabetes care protocols may lead to improved glycemic control and better overall outcomes for T2DM patients . A few studies have established an interconnection between PD and diabetic complication, specifically DR, in T2DM patients, which we aim to highlight in this editorial. Emphasis was placed on the different mechanisms that suggest a bidirectional relationship between PD and T2DM, where the presence of periodontal inflammation negatively influenced glycemic control and contributed to the development and progression of DR through shared inflammatory and vascular mechanisms. This article highlights the importance of collaboration amongst diabetes specialists, ophthalmologists, periodontists, and public health professionals to advance the prevention, early detection, and treatment of PD and DR. This will improve the health and quality of life of T2DM patients. Moreover, the editorial highlights the need for further research on the specific molecular and immunological mechanisms that underlie the link between periodontitis and DR, with identification of common inflammatory biomarkers and signaling pathways. This is expected to facilitate effective direction of therapeutic objectives, thereby improving the management of diabetes and its complications through integrated care that incorporates oral health.

Regulatory role of PDK1 via integrated gene analysis of mitochondria-immune response in periodontitis

AIMS

To investigate the association between mitochondrial events and immune response in periodontitis and related regulatory genes.

MAIN METHODS

Gene expression profiles in gingival tissues were retrieved from the Gene Expression Omnibus. Mitochondria-immune response-related differentially expressed genes (MIR-DEGs) between the healthy and periodontitis samples were determined. WGCNA, GO, and KEGG were used to investigate the function and the enriched pathways of MIR-DEGs. The correlation between MIR-DEGs expression and clinical probing pocket depth was analyzed. The MIR-DEGs were further identified and verified in animal samples. A periodontitis model was established in C57BL/6 mice with silk ligation. Micro-computed tomography was used to assess alveolar bone loss. Western blot, quantitative real-time polymerase chain reaction, and immunohistochemical analyses further validated the differential expression of the MIR-DEGs.

KEY FINDINGS

A total of ten MIR-DEGs (CYP24A1, PRDX4, GLDC, PDK1, BCL2A1, CBR3, ARMCX3, BNIP3, IFI27, and UNG) were identified, the expression of which could effectively distinguish patients with periodontitis from the healthy controls. Enhanced immune response was detected in the periodontitis group with that in the healthy controls, especially in B cells. PDK1 was a critical MIR-DEG correlated with B cell immune response and clinical periodontal probing pocket depth. Both animal and clinical periodontal samples presented higher gene and protein expression of PDK1 than the control samples. Additionally, PDK1 colocalized with B cells in both animal and clinical periodontal tissues.

SIGNIFICANCE

Mitochondria participate in the regulation of the immune response in periodontitis. PDK1 may be the key mitochondria-related gene regulating B-cell immune response in periodontitis.

Mendelian Randomization Reveals No Causal Association Between Periodontitis and Infective Endocarditis

OBJECTIVES

Clarifying the uncertain causal relationship between periodontitis and infective endocarditis using Mendelian randomization analysis, given their historically perceived association and clinical significance.

METHODS

Genetic variation data for acute periodontitis, chronic periodontitis, aggressive periodontitis, and infective endocarditis were obtained from published GWAS in individuals of European ancestry. Instrumental variables significantly associated with periodontitis were selected and univariable Mendelian randomization was conducted to infer the causal association between periodontitis and infective endocarditis. Multivariable Mendelian randomization was also performed to adjust for potential confounders including smoking, drinking, diabetes, and education.

RESULTS

Our analysis found no evidence of a causal association between periodontitis and infective endocarditis, with odds ratios (ORs) of 0.992 (95% CI: 0.879-1.120), 0.947 (95% CI: 0.738-1.214), and 1.056 (95% CI: 0.916-1.217) for acute periodontitis, chronic periodontitis, aggressive periodontitis, respectively. The robustness of our findings was confirmed by heterogeneity tests, pleiotropy tests, leave-one-out analyses, and MR-PRESSO. In the multivariable MR analysis, adjusting for smoking, drinking, diabetes, and education, the overall patterns between genetic liability to periodontitis and infective endocarditis remained consistent (all P > .05).

CONCLUSION

Our findings indicate that there is no genetic causal association between periodontitis and infective endocarditis.

A Mendelian Randomisation Analysis Reveals No Relationship Between Periodontitis and Coronary Atherosclerosis

OBJECTIVES

Growing evidence appears to intimate a profound connection between periodontitis and coronary atherosclerosis (CA), yet the existence of a causal relationship remains unclear. Through the implementation of Mendelian randomization analysis, we further evaluated the potential causal link between chronic/acute periodontitis (CP/AP) and CA.

METHODS

Utilizing genome-wide association study (GWAS) summary statistics, we incorporated periodontitis data derived from European samples (n1 = 198,441; n2 = 195,762) and CA data from 61,194 cases. We conducted a 2 sample, bidirectional Mendelian randomization (MR) analysis using the inverse-variance weighted (IVW) method as the main analytical approach. Supplementary analyses were executed through MR Egger, Weighted median (WM), IVW, Simple mode, and Weighted mode approaches.

RESULTS

The IVW analysis revealed no significant causal relationship between CA and periodontitis (CA-CP: OR = 2.110, 95% CI = 0.208-21.317, P = .527; CA-AP: OR = 0.414, 95% CI = 0.051-3.384, P = .644). Similarly, the bidirectional analysis did not identify impact of periodontitis on CA (OR = 1.000, 95% CI = 0.999-1.001, P = .953). The supplementary analyses corroborated these findings.

CONCLUSIONS

While studies highlighting a correlation between periodontitis and CA, our comprehensive analysis does not corroborate a causal association between periodontitis and CA. Further research is needed to elucidate other potential shared mechanisms and causal evidence between periodontitis and CA.

The oral organ: A new vision of the mouth as a whole for a gerophysiological approach to healthy aging

This article brings a new perspective on oral physiology by presenting the oral organ as an integrated entity within the entire organism and its surrounding environment. Rather than considering the mouth solely as a collection of discrete functions, this novel approach emphasizes its role as a dynamic interphase, supporting interactions between the body and external factors. As a resilient ecosystem, the equilibrium of mouth ecological niches is the result of a large number of interconnected factors including the heterogeneity of different oral structures, diversity of resources, external and internal pressures and biological actors. The manuscript seeks to deepen the understanding of age-related changes within the oral cavity and throughout the organism, aligning with the evolving field of gerophysiology. The strategic position and fundamental function of the mouth make it an invaluable target for early prevention, diagnosis, treatment, and even reversal of aging effects throughout the entire organism. Recognizing the oral cavity capacity for sensory perception, element capture and information processing underscores its vital role in continuous health monitoring. Overall, this integrated understanding of the oral physiology aims at advancing comprehensive approaches to the oral healthcare and promoting broader awareness of its implications on the overall well-being.

Extracellular vesicles-Potential link between periodontal disease and diabetic complications

It has long been suggested that a bidirectional impact exists between periodontitis and diabetes. Periodontitis may affect diabetes glycemic control, insulin resistance, and diabetic complications. Diabetes can worsen periodontitis by delaying wound healing and increasing the chance of infection. Extracellular vesicles (EVs) are heterogeneous particles of membrane-enclosed spherical structure secreted by eukaryotes and prokaryotes and play a key role in a variety of diseases. This review will introduce the biogenesis, release, and biological function of EVs from a microbial and host cell perspective, discuss the functional properties of EVs in the development of periodontitis and diabetes, and explore their role in the pathogenesis and clinical application of these two diseases. Their clinical implication and diagnostic value are also discussed.

Red blood cell folate level is associated with periodontitis in American adults: results from the NHANES 2009-2014

BACKGROUND

Red blood cell (RBC) folate is an indicator of long-term folate nutrition. Whether there is an association between RBC folate and periodontitis is unclear. This study aimed to use the NHANES database to determine whether RBC folate is associated with moderate/severe periodontitis.

METHODS

A cross-sectional analysis of 10,151 participants in the NHANES database from 2009 to 2014 was performed. Multivariate logistic regression was used to analyze the independent relationship between RBC folate and moderate/severe periodontitis. The generalized additive model (GAM), restricted cubic splines (RCS), smooth curve fitting, and threshold effect analysis were used to explore the dose-response relationship and the potential nonlinear relationship between RBC folate and periodontitis. Finally, subgroup analysis and interaction tests were performed to determine the effect of covariates on the relationship between RBC folate and moderate/severe periodontitis.

RESULTS

After adjusting for all confounders, there was a negative association between RBC folate concentration and moderate/severe periodontitis. The lowest fraction Q1 (< 360 ng/mL) of RBC folate concentration was used as the reference group, multivariable-adjusted ORs and 95% CIs of the second (360-463 ng/mL), third (464-569 ng/mL), fourth (570-732 ng/mL), and the highest quintile (> 733 ng/mL) categories were 0.88 (0.77, 1.01), 0.83 (0.72, 0.96), 0.77 (0.67, 0.90), 0.65 (0.56, 0.77) respectively. Additionally, a threshold nonlinear association was found between RBC folate (ng/mL) log2 transformation and moderate/severe periodontitis.

CONCLUSION

This cross-sectional study revealed a negative relationship between RBC folate and moderate/severe periodontitis within a certain threshold range. Dentists and policymakers should pay closer attention to oral hygiene and health care for people with low or high RBC folate levels. Further causal and longitudinal research mechanisms are needed to validate our findings.

Persistent enrichment of multidrug-resistant Klebsiella in oral and nasal communities during long-term starvation

BACKGROUND

The human oral and nasal cavities can act as reservoirs for opportunistic pathogens capable of causing acute infection. These microbes asymptomatically colonize the human oral and nasal cavities which facilitates transmission within human populations via the environment, and they routinely possess clinically significant antibiotic resistance genes. Among these opportunistic pathogens, the Klebsiella genus stands out as a notable example, with its members frequently linked to nosocomial infections and multidrug resistance. As with many colonizing opportunistic pathogens, the essential transmission factors influencing the spread of Klebsiella species among both healthy and diseased individuals remain unclear.

RESULTS

Here, we explored a possible explanation by investigating the ability of oral and nasal Klebsiella species to outcompete their native microbial community members under in vitro starvation conditions, which could be analogous to external hospital environments or the microenvironment of mechanical ventilators. When K. pneumoniae and K. aerogenes were present within a healthy human oral or nasal sample, the bacterial community composition shifted dramatically under starvation conditions and typically became enriched in Klebsiella species. Furthermore, introducing K. pneumoniae exogenously into a native microbial community lacking K. pneumoniae, even at low inoculum, led to repeated enrichment under starvation. Precise monitoring of K. pneumoniae within these communities undergoing starvation indicated rapid initial growth and prolonged viability compared to other members of the microbiome. K. pneumoniae strains isolated from healthy individuals' oral and nasal cavities also exhibited resistance to multiple classes of antibiotics and were genetically similar to clinical and gut isolates. In addition, we found that in the absence of Klebsiella species, other understudied opportunistic pathogens, such as Peptostreptococcus, increased in relative abundance under starvation conditions.

CONCLUSIONS

Our findings establish an environmental and microbiome community circumstance that allows for the enrichment of Klebsiella species and other opportunistic pathogens. Klebsiella's enrichment may hinge on its ability to quickly outgrow other members of the microbiome. The ability to outcompete other commensal bacteria and to persist under harsh environmental conditions could be an important factor that contributes to enhanced transmission in both commensal and pathogenic contexts. Video Abstract.

Early detection of cardiovascular risk markers through non-invasive ultrasound methodologies in periodontitis patients

Objectives

This narrative review aims to update the current evidence and offer insight into the new non-invasive ultrasound techniques used to early identify degenerative vascular changes in subjects with periodontitis and to investigate if these methodologies could be useful to identify subclinical cardiovascular disease (CVD) dysfunction in periodontitis patients and to monitor changes in CVD risk after periodontal treatment.

Methods

Studies examining the assessment of vascular endothelial function through the latest methodologies were analyzed. Systematic reviews, observational studies, and clinical trials in the English language were identified using PubMed, Web of Science, and Google Scholar databases with key search terms such as "periodontitis," "endothelial dysfunction (ED)," "arterial stiffness," and "periodontal therapy."

Results

Several mechanisms are involved in the association between periodontitis and CVD. The key players are periodontal bacteria and their toxins, which can enter the circulation and infiltrate blood vessel walls. The increase in proinflammatory molecules such as interleukins and chemokines, c-reactive protein, fibrinogen, and oxidative stress also plays a decisive role. In addition, an increase in parameters of ED, arterial stiffness, and atherosclerosis, such as carotid intima-media thickness, pulse wave velocity, and flow-mediated dilatation, has been shown in periodontal patients.

Conclusions

The literature today agrees on the association of periodontitis and CVD and the positive role of periodontal therapy on systemic inflammatory indices and cardiovascular outcomes. Hopefully, these non-invasive methodologies could be extended to periodontal patients to provide a comprehensive understanding of the CVD-periodontitis link from the perspective of a personalized medicine approach in periodontology.

Systematic review to evaluate accuracy studies of the diagnostic criteria for periodontitis in pregnant women

The diversity of criteria used in the diagnosis of periodontitis in pregnant women makes it difficult to define and compare the disease. Using a systematic review, this study evaluated the accuracy of criteria for diagnosing periodontitis in pregnant women. Searches were carried out in the databases: Medline/PubMed, Embase, Scopus, Web of Science, SciELO, Lilacs, ProQuest, and CINAHL. Validation studies of the criteria used for diagnosing periodontitis met the inclusion criteria. The study steps were performed by three independent reviewers. A qualitative synthesis of the included articles was carried out and the quality methodological analysis using the QUADAS-2 instrument. The assessment of the quality of the evidence was obtained through the GRADE tool. A total of 592 records were identified, of which only 6 made up this systematic review. The included studies analyzed different criteria for diagnosing periodontitis, evaluating 3,005 pregnant women. The criteria selected as a test presented results equivalent to the performance of those recognized as the gold standard. The self-reported criteria were of lower diagnostic accuracy. A major limitation of this review was the small number of primary studies that evaluated clinical diagnosis of periodontitis in pregnant women, which was highly heterogeneous, making it impossible to carry out accuracy meta-analysis and additional analyzes. There is a lack of consensus on the criteria for the diagnosis of periodontitis, with great variability in the accuracy and prevalence of the disease in pregnant women.

Hepatitis B infection is associated with periodontitis: the national health and nutrition examination survey (2009-2014)

BACKGROUND

Current research has been inconclusive regarding whether hepatitis B infection is associated with an increased risk of periodontitis. This study aims to test the null hypothesis that no association exists between hepatitis B infection and an increased risk of periodontitis using the National Health and Nutrition Examination Survey (2009-2014).

METHODS

We performed a cross-sectional study using the National Health and Nutrition Examination Survey (NHANES) database (2009-2014) to assess the rate of the prevalence of periodontitis in patients with and without hepatitis B infection. Participants who had tested for hepatitis B and periodontitis were included. The included participants were divided into no/mild periodontitis and moderate/severe periodontitis groups according to their periodontal status. The association between hepatitis B infection and chronic periodontitis was evaluated by multivariable regression analyses adjusting for age, gender, race/ethnicity, education level, income-to-poverty ratio, smoking, alcohol, BMI, ALT, AST, creatinine, hypertension, and diabetes.

RESULTS

A total of 5957 participants were included and divided into two groups: inactive periodontitis group (n = 3444) and active periodontitis group (n = 2513). The results showed that participants with hepatitis B had a higher risk of periodontitis. After adjusting for covariables, adults with hepatitis B infection were 38% more likely to have periodontitis compared to those without hepatitis B infection (95% Confidence Interval [CI]:1.085-1.754).

CONCLUSIONS

In general, the results suggest that CHB is positively associated with the more severe periodontitis. These results suggest that people with hepatitis B infection should take good periodontal care measures to avoid the occurrence and development of periodontitis.

Causal role of immune cells in chronic periodontitis: a bidirectional Mendelian randomization study

BACKGROUND

This study aims to explore the bidirectional causal relationship between immune cell phenotypes and chronic periodontitis using a Mendelian randomization framework.

MATERIALS AND METHODS

Through a two-sample Mendelian randomization analysis, this research examined genetic data related to 731 immune cell traits and chronic periodontitis. Instrumental variables were chosen based on their genetic links to either immune traits or periodontitis. Various statistical techniques, including MR-Egger regression, weighted median, and inverse-variance weighted (IVW) analysis, were employed to determine the causal connections.

RESULTS

Predominantly using the IVW method, 26 distinct immune phenotypes were identified as potentially influencing periodontitis (P < 0.05). Conversely, periodontitis potentially affected 33 different immune phenotypes (P < 0.05). The results for pleiotropy and sensitivity tests were stable. However, these associations lost significance after adjusting for the False Discovery Rate.

CONCLUSION

This study uncovers a complex bidirectional causal relationship between certain immune cell phenotypes and chronic periodontitis, underscoring the intricate interaction between the immune system and the pathogenesis of periodontal disease.

Considerations for oral and dental tissues in holistic care during long-haul space flights

The health of astronauts during and after the return from long-haul space missions is paramount. There is plethora of research in the literature about the medical side of astronauts' health, however, the dental and oral health of the space crew seem to be overlooked with limited information in the literature about the effects of the space environment and microgravity on the oral and dental tissues. In this article, we shed some light on the latest available research related to space dentistry and provide some hypotheses that could guide the directions of future research and help maintain the oral health of space crews. We also promote for the importance of regenerative medicine and dentistry as well highlight the opportunities available in the expanding field of bioprinting/biomanufacturing through utilizing the effects of microgravity on stem cells culture techniques. Finally, we provide recommendations for adopting a multidisciplinary approach for oral healthcare during long-haul space flights.

Evaluating the impact of oral hygiene instruction and digital oral health education within cardiac rehabilitation clinics: A protocol for a novel, dual centre, parallel randomised controlled trial

INTRODUCTION

Diseases of the periodontal tissues including gingivitis and periodontitis can affect up to 90% and 50% of the population respectively. These conditions are multifactorial inflammatory conditions involving a dysbiotic biofilm that, if left untreated, can lead to the destruction of the supporting structures of the teeth and have significant systemic implications, specifically on cardiovascular health. The elevation of inflammatory markers, particularly high-sensitive C-reactive protein (hsCRP), are strongly associated with an increased risk of atherosclerosis, a key risk factor for cardiovascular disease (CVD). HsCRP as well as other inflammatory markers can be detected in blood samples as early as 21 days after ceasing toothbrushing, due to the immune response to stagnant oral biofilm. The most effective way to ensure oral biofilm cannot remain on oral tissues, thus preventing periodontitis and reducing inflammatory CVD risk, is with good oral hygiene. The primary aim of this study is to assess whether individualised oral hygiene instruction (OHI) partnered with a digital oral health education (DOHE) package can improve the oral health of patients living with CVD.

METHODS AND ANALYSIS

A total of 165 participants will be recruited from the Westmead and Blacktown Mt Druitt cardiac rehabilitation out-patient clinics into this dual centre, single blind, parallel design, randomised controlled trial. A baseline oral health clinical examination will be completed, followed by a self-report questionnaire before they are randomised in a 1:1:1 ratio into one of 3 arms as follows: individualised OHI partnered with DOHE (Group A), (Group B) DOHE only (Group B), and control/usual care (no oral health education) (Group C). Groups will have their intervention repeated at the 6-week follow-up. After completing the 12-week follow-up, Group B and Group C will receive tailored OHI. Group C will also receive the DOHE package. The primary outcome is the change in approximal plaque index score between baseline and 6-week follow up.

ETHICS AND DISSEMINATION

The study has been approved by the Western Sydney Local Health District Human Ethics Committee 2023/ETH00516. Results will be published in peer-reviewed journals and presented at conferences.

TRIAL REGISTRATION NUMBER

ACTRN12623000449639p ANZCTR: https://www.anzctr.org.au/.

A Flagellin-Adjuvanted Trivalent Mucosal Vaccine Targeting Key Periodontopathic Bacteria

Periodontal disease (PD) is caused by microbial dysbiosis and accompanying adverse inflammatory responses. Due to its high incidence and association with various systemic diseases, disease-modifying treatments that modulate dysbiosis serve as promising therapeutic approaches. In this study, to simulate the pathophysiological situation, we established a "temporary ligature plus oral infection model" that incorporates a temporary silk ligature and oral infection with a cocktail of live Tannerella forsythia (Tf), Pophyromonas gingivalis (Pg), and Fusobacterium nucleatum (Fn) in mice and tested the efficacy of a new trivalent mucosal vaccine. It has been reported that Tf, a red complex pathogen, amplifies periodontitis severity by interacting with periodontopathic bacteria such as Pg and Fn. Here, we developed a recombinant mucosal vaccine targeting a surface-associated protein, BspA, of Tf by genetically combining truncated BspA with built-in adjuvant flagellin (FlaB). To simultaneously induce Tf-, Pg-, and Fn-specific immune responses, it was formulated as a trivalent mucosal vaccine containing Tf-FlaB-tBspA (BtB), Pg-Hgp44-FlaB (HB), and Fn-FlaB-tFomA (BtA). Intranasal immunization with the trivalent mucosal vaccine (BtB + HB + BtA) prevented alveolar bone loss and gingival proinflammatory cytokine production. Vaccinated mice exhibited significant induction of Tf-tBspA-, Pg-Hgp44-, and Fn-tFomA-specific IgG and IgA responses in the serum and saliva, respectively. The anti-sera and anti-saliva efficiently inhibited epithelial cell invasion by Tf and Pg and interfered with biofilm formation by Fn. The flagellin-adjuvanted trivalent mucosal vaccine offers a novel method for modulating dysbiotic bacteria associated with periodontitis. This approach leverages the adjuvant properties of flagellin to enhance the immune response, aiming to restore a balanced microbial environment and improve periodontal health.

ML-Based Edge Node for Monitoring Peoples' Frailty Status

The development of contactless methods to assess the degree of personal hygiene in elderly people is crucial for detecting frailty and providing early intervention to prevent complete loss of autonomy, cognitive impairment, and hospitalisation. The unobtrusive nature of the technology is essential in the context of maintaining good quality of life. The use of cameras and edge computing with sensors provides a way of monitoring subjects without interrupting their normal routines, and has the advantages of local data processing and improved privacy. This work describes the development an intelligent system that takes the RGB frames of a video as input to classify the occurrence of brushing teeth, washing hands, and fixing hair. No action activity is considered. The RGB frames are first processed by two Mediapipe algorithms to extract body keypoints related to the pose and hands, which represent the features to be classified. The optimal feature extractor results from the most complex Mediapipe pose estimator combined with the most complex hand keypoint regressor, which achieves the best performance even when operating at one frame per second. The final classifier is a Light Gradient Boosting Machine classifier that achieves more than 94% weighted F1-score under conditions of one frame per second and observation times of seven seconds or more. When the observation window is enlarged to ten seconds, the F1-scores for each class oscillate between 94.66% and 96.35%.

Curcumin inhibits growth of Porphyromonas gingivalis by arrest of bacterial dipeptidyl peptidase activity

Background

Curcumin is a multi-functional polyphenol with anti-bacterial and anti-inflammatory effects and may have potential for treatment of periodontal diseases. The present study was conducted to examine the molecular basis of the anti-bacterial effect of curcumin against Porphyromonas gingivalis using metabolome analysis.

Materials and Methods

P. gingivalis were incubated with 10 µg/mL curcumin, and then metabolites were analyzed with CE-TOF/MS. Expression levels of sigma factors were also evaluated using RT-PCR assays. The activities of dipeptidyl peptidases (DPPs) were assessed by examining the degradation reactions of MCA-labeled peptides.

Results

The relative amounts of various glycogenic amino acids were significantly decreased when P. gingivalis was incubated with curcumin. Furthermore, the metabolites on the amino acid degradation pathway, including high-energy compounds such as ATP, various intermediate metabolites of RNA/DNA synthesis, nucleoside sugars and amino sugars were also decreased. Additionally, the expression levels of sigma-54 and sigma-70 were significantly decreased, and the same results as noted following nutrient starvation. Curcumin also significantly suppressed the activities of some DPPs, while the human DPP-4 inhibitors markedly inhibited the growth of P. gingivalis and activities of the DPPs.

Conclusions

Curcumin suppresses the growth of P. gingivalis by inhibiting DPPs and also interferes with nucleic acid synthesis and central metabolic pathways, beginning with amino acid metabolism.

Clinico-immunological evaluation of use of omega-3 fatty acids as nutraceutical approach in management of patients with chronic periodontitis: A randomized clinical trial

Background

Subgingival bacterial colonization and biofilm formation are known to be the main etiology of periodontal disease progression. This biofilm elicits host response and the interaction between host defence mechanisms with plaque microorganisms and their products results in periodontal disease. Host modulatory therapy (HMT) is a form of treatment of periodontitis that focuses on treatment of the host in the host-bacteria interaction. Omega-3 fatty acids have emerged as a potential HMT agent to treat inflammation associated with periodontal disease.

Methods

A total of 60 cases of chronic periodontitis were allocated into two groups; the test group (n = 30) were treated with scaling and root planing (SRP) and given a dietary supplementation of omega-3 fatty acid while the control group were treated with SRP alone. Clinical parameters carried out were plaque index (PI), gingival bleeding index (GBI), pocket probing depth (PPD) and clinical attachment level (CAL) and immunological parameter included interleukin-1β level in saliva at baseline, 3 months and 6 months after therapy.

Results

At 6 months, both the groups showed significant improvements with regards to all clinical and immunological parameters compared to baseline (all p < 0.05). However, test group presented with more favourable statistically significant results.

Conclusion

The use of omega-3 fatty acid as nutraceutical agent to conventional method acted as beneficial therapeutic measures and effective in patients with chronic periodontitis when compared with SRP alone.

Role of Nonalcoholic Fatty Liver Disease in Periodontitis: A Bidirectional Relationship

Nonalcoholic fatty liver disease (NAFLD) and periodontitis share common risk factors such as obesity, insulin resistance (IR), and dyslipidemia, which contribute to systemic inflammation. It has been suggested that a bidirectional relationship exists between NAFLD and periodontitis, indicating that one condition may exacerbate the other. NAFLD is characterized by excessive fat deposition in the liver and is associated with low-grade chronic inflammation. There are several risk factors for the development of NAFLD, including gender, geriatric community, race, ethnicity, poor sleep quality and sleep deprivation, physical activity, nutritional status, dysbiosis gut microbiota, increased oxidative stress, overweight, obesity, higher body mass index (BMI), IR, type 2 diabetes mellitus (T2DM), metabolic syndrome (MetS), dyslipidemia (hypercholesterolemia), and sarcopenia (decreased skeletal muscle mass). This systemic inflammation can contribute to the progression of periodontitis by impairing immune responses and exacerbating the inflammatory processes in the periodontal tissues. Furthermore, individuals with NAFLD often exhibit altered lipid metabolism, which may affect oral microbiota composition, leading to dysbiosis and increased susceptibility to periodontal disease. Conversely, periodontitis has been linked to the progression of NAFLD through mechanisms involving systemic inflammation and oxidative stress. Chronic periodontal inflammation can release pro-inflammatory cytokines and bacterial toxins into the bloodstream, contributing to liver inflammation and exacerbating hepatic steatosis. Moreover, periodontitis-induced oxidative stress may promote hepatic lipid accumulation and IR, further aggravating NAFLD. The interplay between NAFLD and periodontitis underscores the importance of comprehensive management strategies targeting both conditions. Lifestyle modifications such as regular exercise, a healthy diet, and proper oral hygiene practices are crucial for preventing and managing these interconnected diseases. Additionally, interdisciplinary collaboration between hepatologists and periodontists is essential for optimizing patient care and improving outcomes in individuals with NAFLD and periodontitis.

Bidirectional Association between Periodontitis and Thyroid Disease: A Scoping Review

Periodontitis is a chronic inflammatory disease of the tissues surrounding and supporting the teeth. Due to the development of chronic inflammation, periodontitis can contribute to the development of several systemic diseases, including thyroid disease. Thyroid pathology includes benign, malignant, and autoimmune conditions leading to hypothyroidism, hyperthyroidism, or euthyroidism. Alterations in thyroid hormones, especially hypothyroidism, can reveal significant oral manifestations, including periodontitis. This scoping review aims to explore the probable causal relationship between periodontitis and thyroid disease, in terms of epidemiology, pathogenesis, and treatment. The search strategy follows the PRISMA-ScR guidelines. PubMed, Scopus, Web of Science, and Cochrane were searched from January 2014 to January 2024, entering the MESH terms "periodontitis" and "thyroid". Of 153 initial records, 20 articles were selected and discussed. There is a high prevalence of periodontitis among patients with thyroid disease, including thyroid cancer. The causes at the basis of this association are genetic factors, the oral microbiome, and proinflammatory cytokines. Periodontal treatment, specifically scaling and root planning, can ameliorate thyroid parameters. Although there are a few randomized controlled studies in the literature, this review lays the foundation for a bidirectional relationship between periodontitis and thyroid disease, the link to which is, once again, systemic inflammation.

Integrating network pharmacology and experimental evaluation to explore the complementary therapeutic effect and mechanism of melatonin in periodontitis

Objective

To explore the potential targets for melatonin in the treatment of periodontitis through network pharmacologic analysis and experimental validation via in vivo animal models and in vitro cellular experiments.

Materials and methods

In this study, we first screened melatonin targets from Pharm Mapper for putative targets, Drug Bank, and TCMSP databases for known targets. Then, disease database was searched and screened for differential expressed genes associated with periodontitis. The intersection of disease and melatonin-related genes yielded potential target genes of melatonin treatment for periodontitis. These target genes were further investigated by protein-protein interaction network and GO/KEGG enrichment analysis. In addition, the interactions between melatonin and key target genes were interrogated by molecular docking simulations. Then, we performed animal studies to validate the therapeutic effect of melatonin by injecting melatonin into the peritoneal cavity of ligation-induced periodontitis (LIP) mice. The effects of melatonin on the predicted target proteins were also analyzed using Western blot and immunofluorescence techniques. Finally, we constructed an in vitro cellular model and validated the direct effect of melatonin on the predicted targets by using qPCR.

Results

We identified 8 potential target genes by network pharmacology analysis. Enrichment analysis suggests that melatonin may treat periodontitis by inhibiting the expression of three potential targets (MPO, MMP8, and MMP9). Molecular docking results showed that melatonin could effectively bind to MMP8 and MMP9. Subsequently, melatonin was further validated in a mouse LIP model to inhibit the expression of MPO, MMP8, and MMP9 in the periodontal tissue. Finally, we verified the direct effect of melatonin on the mRNA expression of MPO, MMP8, and MMP9 in an in vitro cellular model.

Conclusions

Through a combination of network pharmacology and experimental validation, this study provides a more comprehensive understanding of the mechanism of melatonin to treat periodontitis. Our study suggests that MPO, MMP8, and MMP9 as key target genes of melatonin to treat periodontitis. These findings present a more comprehensive basis for further investigation into the mechanisms of pharmacological treatment of periodontitis by melatonin.

Impact of Periodontitis on Endothelial Risk Dysfunction and Oxidative Stress Improvement in Patients with Cardiovascular Disease

Periodontitis is a multifactorial chronic inflammatory disease that affects the periodontium and overall oral health and is primarily caused by a dysbiotic gingival biofilm, which includes, among others, Gram-negative bacteria such as Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, and Tannerella forsythensis that colonize gingival tissues and that can lead, if not properly treated, to periodontal tissue destruction and tooth loss. In the last few decades, several large-scale epidemiological studies have evidenced that mild and severe forms of periodontitis are strictly bilaterally associated with several cardiovascular diseases (CVDs), stroke, and endothelial dysfunction. Specifically, it is hypothesized that patients with severe periodontitis would have compromised endothelial function, a crucial step in the pathophysiology of atherosclerosis and several CVD forms. In this regard, it was postulated that periodontal treatment would ameliorate endothelial dysfunction, hence bolstering the notion that therapeutic approaches targeted at diminishing cardiovascular risk factors and different forms of periodontal treatment could improve several CVD biomarker outcomes in the short- and long-term in CVD patients. The aim of this review is to update and analyze the link between periodontitis and CVD, focusing on the inflammatory nature of periodontitis and its correlation with CVD, the effects of periodontal therapy on endothelial dysfunction and oxidative stress, and the impact of such therapy on CVD biomarkers and outcomes. The article also discusses future research directions in this field.

Evidence of microbiota-host dysbiosis between periodontitis and cerebral small vessel disease

OBJECTIVES

To investigate the correlation between periodontitis and cerebral small vessel disease (CSVD) from the clinical and microbiological aspects.

SUBJECTS AND METHODS

Periodontitis patients (CP group, n = 31) and CSVD patients (CSVD group, n = 30) were examined for neurological and periodontal condition. Subgingival plaque was collected and performed using 16S rRNA sequencing. Logistic regression and LASSO regression were used to analyze the periodontal parameters and subgingival microbiota related to CSVD, respectively. Inflammatory factors in gingival crevicular fluid (GCF) were also detected and compared between the two groups.

RESULTS

Clinical attachment level (CAL), teeth number and plaque index demonstrated a significant difference between CP and CSVD group, meanwhile, CAL was independently associated with CSVD. Besides, the microbial richness and composition were distinct between two groups. Five genera related to periodontal pathogens (Treponema, Prevotella, Streptococcus, Fusobacterium, Porphyromonas) were screened out by LASSO regression, suggesting a potential association with CSVD. Finally, the levels of inflammatory factors in GCF were statistically higher in CSVD group than those in CP group.

CONCLUSIONS

Cerebral small vessel disease patients demonstrated worse periodontal condition, meanwhile the interaction between microbiota dysbiosis and host factors (inflammation) leading to a better understanding of the association between periodontitis and CSVD.

Molecularly imprinted nanogels as synthetic recognition materials for the ultrasensitive detection of periodontal disease biomarkers

Periodontal disease affects supporting dental structures and ranks among one of the top most expensive conditions to treat in the world. Moreover, in recent years, the disease has also been linked to cardiovascular and Alzheimer's diseases. At present, there is a serious lack of accurate diagnostic tools to identify people at severe risk of periodontal disease progression. Porphyromonas gingivalis is often considered one of the most contributing factors towards disease progression. It produces the Arg- and Lys-specific proteases Rgp and Kgp, respectively. Within this work, a short epitope sequence of these proteases is immobilised onto a magnetic nanoparticle platform. These are then used as a template to produce high-affinity, selective molecularly imprinted nanogels, using the common monomers N-tert-butylacrylamide (TBAM), N-isopropyl acrylamide (NIPAM), and N-(3-aminopropyl) methacrylamide hydrochloride (APMA). N,N-Methylene bis(acrylamide) (BIS) was used as a crosslinking monomer to form the interconnected polymeric network. The produced nanogels were immobilised onto a planar gold surface and characterised using the optical technique of surface plasmon resonance. They showed high selectivity and affinity towards their template, with affinity constants of 79.4 and 89.7 nM for the Rgp and Kgp epitope nanogels, respectively. From their calibration curves, the theoretical limit of detection was determined to be 1.27 nM for the Rgp nanogels and 2.00 nM for the Kgp nanogels. Furthermore, they also showed excellent selectivity against bacterial culture supernatants E8 (Rgp knockout), K1A (Kgp knockout), and W50-d (wild-type) strains in complex medium of brain heart infusion (BHI).

Oral health education strategies for patients living with cardiovascular disease within hospital settings: a scoping review

Objective

To identify and describe the impact of current oral health education programmes provided to patients in cardiology hospital wards and outpatient clinics.

Methods

This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Scoping Reviews statement. Searches were conducted using electronic databases: Cochrane, Medline, and Scopus, as well as grey literature searching.

Results

Three eligible studies were identified. All included studies reported generalised poor oral health in their participants at baseline, with significant improvement at follow-up. They all reported significant reductions in plaque deposits and gingival bleeding. One study reported significantly less bacteria on participant tongues, as well as fewer days with post-operative atrial fibrillation in the intervention group. Furthermore, in this study, one patient in the intervention group developed pneumonia, whilst four patients in the control group did.

Conclusion

Oral health education for patients with cardiovascular disease is limited and many have poor oral health. Educational programmes to improve oral health behaviours in patients with cardiovascular disease can improve both oral and general health outcomes.

Implications for public health

Oral disease is a modifiable risk factor for cardiovascular disease. Integrating oral health education into cardiology hospital settings is a simple strategy to improve access to oral health information and improve both oral and cardiovascular outcomes.

Periodontal inflammation as a potential driver of HIV low level viremia

HIV can be successfully suppressed to undetectable levels by antiretroviral therapy (ART) in most people with HIV (PWH). However, a small proportion continues to have persistent low-level viremia (LLV) during ART. A presumed source of LLV is production or replication from viral reservoirs, which are maintained in the presence of ART. It is unknown whether the oral cavity can be considered an HIV reservoir. As periodontal inflammation is a common problem in PWH, we hypothesize that periodontal inflammation in the oral cavity activates (latently) infected cells and thus might be associated with LLV. We included 11 individuals with HIV LLV, and compared HIV-RNA levels in saliva and plasma at baseline and at week 24 after switch of ART. We compared the LLV-group at baseline with 11 age-matched controls with suppressed viremia. To investigate the severity of periodontitis we used Periodontal Inflamed Surface Areas (PISA) by measuring probing depth, gingival recession, bleeding on probing and clinical attachment level. Severity of periodontitis was classified according to the CDC-AAP case definition. Additional insights in periodontal inflammation were obtained by comparing immune activation markers and the presence of periodontal pathogens. In four individuals of the LLV group, residual levels of HIV-RNA were detected in saliva at baseline (N = 1) or at week 24 (N = 2) or both (N = 1). Of the four individuals with LLV, three had residual levels of HIV-RNA in saliva. All 22 individuals had moderate to severe periodontitis. PISA was not significantly different between cases with LLV and controls. Similarly, periodontal pathogens were frequently observed in both groups. Total activated HLA-DR+CD38+ CD4+ cells and CD8+ cells were significantly higher in the LLV group than in the control group (p = <0.01). No immune markers were associated with LLV. In conclusion, periodontal inflammation is an unlikely driver of HIV LLV compared to HIV suppressed individuals.

Bacteria of healthy periodontal tissues as candidates of probiotics: a systematic review

OBJECTIVES

The use of probiotics could promote the balance of the subgingival microbiota to contribute to periodontal health. This study aimed to identify the potential of bacteria commonly associated with healthy periodontal tissues as probiotic candidates.

MATERIAL AND METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed, Scopus, Science Direct, ProQuest, and Ovid databases as well as the combination of Medical Subject Headings (MeSH) and non-MeSH terms. Based on the selection criteria, original studies published in English and identifying the microorganisms present in the periodontium of healthy individuals and patients with periodontitis using the high-throughput 16S ribosomal gene sequencing technique were included.

RESULTS

Out of 659 articles, 12 met the criteria for this review. These articles were published from 2012 to 2020 and mainly originated from the United States, China, and Spain. Most of these studies reported adequate criteria for selecting participants, using standardized clinical criteria, and compliance with quality based on the tools used. In periodontal healthy tissue were identified species like Actinomyces viscosus, Actinomyces naeslundii, Haemophilus parainfluenzae, Rothia dentocariosa, Streptococcus sanguinis, Streptococcus mitis, Streptococcus oralis, Streptococcus gordonii, Streptococcus intermedius, and Prevotella nigrescens which have recognized strains with a capacity to inhibit periodontopathogens.

CONCLUSIONS

S. sanguinis, S. oralis, S. mitis, and S. gordonii are among the bacterial species proposed as potential probiotics because some strains can inhibit periodontopathogens and have been reported as safe for humans.

Long intergenic non-coding RNA 01126 activates IL-6/JAK2/STAT3 pathway to promote periodontitis pathogenesis

OBJECTIVES

Periodontitis seriously affects oral-related quality of life and overall health. Long intergenic non-coding RNA 01126 (LINC01126) is aberrantly expressed in periodontitis tissues. This study aimed to explore the possible pathogenesis of LINC01126 in periodontitis.

METHODS

Inflammatory model of human gingival fibroblasts (HGFs) was established. Cell Counting Kit-8 (CCK-8), wound healing assay, and flow cytometry were utilized to detect biological roles of LINC01126. Binding site of miR-655-3p to LINC01126 and IL-6 was predicted. Then, subcellular localization of LINC01126 and the binding ability of miR-655-3p to LINC01126 and IL-6 in HGFs were verified. Hematoxylin-Eosin (H&E) staining and immunohistochemistry (IHC) staining were utilized to detect tissue morphology and proteins expression of clinical samples.

RESULTS

LINC01126 silencing can alleviate cell inflammation induced by lipopolysaccharide derived from Porphyromonas gingivalis, reduce cell apoptosis, and promote cell migration. As a "sponge" for miR-655-3p, LINC01126 inhibits its binding to mRNA of IL-6, thereby promoting inflammation progression and JAK2/STAT3 pathway activation. Quantitative real-time PCR, Western Blot, and IHC results of clinical tissue samples further confirmed that miR-655-3p expression was down-regulated and IL-6/JAK2/STAT3 was abnormally activated in periodontitis tissues.

CONCLUSIONS

In summary, serving as an endogenous competitive RNA of miR-655-3p, LINC01126 promotes IL-6/JAK2/STAT3 pathway activation, thereby promoting periodontitis pathogenesis.

Exploring gut microbiota's role in rheumatic valve disease: insights from a Mendelian randomization study and mediation analysis

Background

Investigating the relationship between gut microbiota and Rheumatic Valve Disease (RVD) is crucial for understanding the disease's etiology and developing effective interventions. Our study adopts a novel approach to examine the potential causal connections between these factors.

Methods

Utilizing a two-sample Mendelian Randomization (MR) framework, we incorporated a multi-variable MR (MVMR) strategy to assess the mediatory mechanisms involved. This approach involved analyzing data from the MiBioGen consortium for gut microbiota and the FinnGen for RVD, among other sources. Instrumental variables (IVs) were carefully selected based on rigorous MR principles, and statistical analysis was conducted using bidirectional two-sample MR, such as inverse variance-weighted (IVW), weighted median, MR-Egger regression and MR Steiger Test methods. The MR-PRESSO strategy was employed for outlier detection, and MVMR was used to untangle the complex relationships between multiple microbiota and RVD.

Results

Our analysis highlighted several gut microbiota classes and families with potential protective effects against RVD, including Lentisphaerae, Alphaproteobacteria, and Streptococcaceae. In contrast, certain genera, such as Eubacterium eligens and Odoribacter, were identified as potential risk factors. The MVMR analysis revealed significant mediation effects of various immune cell traits and biomarkers, such as CD4-CD8- T cells, CD3 on Terminally Differentiated CD8+ T cell and Pentraxin-related protein PTX, elucidating the complex pathways linking gut microbiota to RVD.

Conclusion

This study underscores the intricate and potentially causal relationship between gut microbiota and RVD, mediated through a range of immune and hormonal factors. The use of MVMR in our methodological approach provides a more comprehensive understanding of these interactions, highlighting the gut microbiota's potential as therapeutic targets in RVD management. Our findings pave the way for further research to explore these complex relationships and develop targeted interventions for RVD.

TPG-functionalized PLGA/PCL nanofiber membrane facilitates periodontal tissue regeneration by modulating macrophages polarization via suppressing PI3K/AKT and NF-κB signaling pathways

Traditional fibrous membranes employed in guided tissue regeneration (GTR) in the treatment of periodontitis have limitations of bioactive and immunomodulatory properties. We fabricated a novel nTPG/PLGA/PCL fibrous membrane by electrospinning which exhibit excellent hydrophilicity, mechanical properties and biocompatibility. In addition, we investigated its regulatory effect on polarization of macrophages and facilitating the regeneration of periodontal tissue both in vivo and in vitro. These findings showed the 0.5%TPG/PLGA/PCL may inhibit the polarization of RAW 264.7 into M1 phenotype by suppressing the PI3K/AKT and NF-κB signaling pathways. Furthermore, it directly up-regulated the expression of cementoblastic differentiation markers (CEMP-1 and CAP) in periodontal ligament stem cells (hPDLSCs), and indirectly up-regulated the expression of cementoblastic (CEMP-1 and CAP) and osteoblastic (ALP, RUNX2, COL-1, and OCN) differentiation markers by inhibiting the polarization of M1 macrophage. Upon implantation into a periodontal bone defect rats model, histological assessment revealed that the 0.5%TPG/PLGA/PCL membrane could regenerate oriented collagen fibers and structurally intact epithelium. Micro-CT (BV/TV) and the expression of immunohistochemical markers (OCN, RUNX-2, COL-1, and BMP-2) ultimately exhibited satisfactory regeneration of alveolar bone, periodontal ligament. Overall, 0.5%TPG/PLGA/PCL did not only directly promote osteogenic effects on hPDLSCs, but also indirectly facilitated cementoblastic and osteogenic differentiation through its immunomodulatory effects on macrophages. These findings provide a novel perspective for the development of materials for periodontal tissue regeneration.

IL-37 evaluation in chronic periodontitis after periodontal treatment with and without low level laser therapy

BACKGROUND

Periodontal disease poses a significant global health challenge. Traditional treatments focus on reducing inflammation and bacterial load, yet novel approaches are continually being investigated. Recent research suggests that IL-37, a potent anti-inflammatory cytokine, may play a crucial role in modulating the inflammatory processes associated with periodontal disease. In conjunction with IL-37, low-level laser therapy (LLLT) has gained attention for its potential in promoting tissue repair, reducing inflammation, and enhancing cellular processes. This study aims to investigate the effects of LLLT on IL-37 in periodontal disease management.

METHODS

Thirty patients were enrolled: the G1 group patients were treated with only scaling and root planning-SRP, the G2 group was treated with SRP and LLLT. Before treatment (T0) all periodontal probing pocket depth and bleeding on probing were obtained. Before (T0) and 10 (T1), 30 (T2) and 60 (T3) days after treatment, was achieved plaque sample and specimens of gingival crevicular fluid. Diode laser wavelength range was used between 600-1000 nm and 0.04-60 J/cm2 energy density for 3-s spotlights.

RESULTS

In all patients PPD, BOP and IL-37 have shown healing improved parameters.

CONCLUSIONS

Although LLLT is widely recommended for its biostimulatory and anti-inflammatory roles, it only showed additional short-term merits in reducing the pocket depth after conventional SRP. Its long-term adjunctive benefits remain unclear. Future RCTs with better study designs, adequate sample power and longer durations of follow-up are required to assess the effectiveness of LLLT as an adjunctive treatment strategy in patients with periodontal disease.

Porphyromonas gingivalis interaction with Candida albicans allows for aerobic escape, virulence and adherence

In the oral cavity Candida albicans interacts with many oral bacteria, including Porphyromonas gingivalis, both physically and metabolically. The aim of this in vitro study was to characterize these interactions and study their effects on the survival of P. gingivalis. First, metabolic interactions were evaluated by counting the colony forming units (CFU) after co-culturing. The results indicated that the anaerobic bacterium P. gingivalis survives under aerobic conditions when co-cultured with C. albicans. This is due to the oxygen consumption by C. albicans as determined by a reduction in survival upon the addition of Antimycin A. By measuring the protease activity, it was found that the presence of C. albicans induced gingipain activity by P. gingivalis, which is an important virulence factor. Adherence of P. gingivalis to hyphae of C. albicans was observed with a dynamic flow system. Using various C. albicans mutants, it was shown that the mechanism of adhesion was mediated by the cell wall adhesins, members of the agglutinin-like sequence (Als) family: Als3 and Als1. Furthermore, the two microorganisms could be co-cultured into forming a biofilm in which P. gingivalis can survive under aerobic culturing conditions, which was imaged using scanning electron microscopy. This study has further elucidated mechanisms of interaction, virulence acquisition and survival of P. gingivalis when co-cultured with C. albicans. Such survival could be essential for the pathogenicity of P. gingivalis in the oxygen-rich niches of the oral cavity. This study has emphasized the importance of interaction between different microbes in promoting survival, virulence and attachment of pathogens, which could be essential in facilitating penetration into the environment of the host.

Influence of periodontal status on patients undergoing hematopoietic stem cell transplantation: A retrospective analysis

Objective

This retrospective analysis aimed to evaluate the prevalence of periodontitis in patients undergoing hematopoietic stem cell transplantation, and investigate the effects of various periodontal statuses and risk factors on oral infection incidence.

Study design

Medical records of patients pre- and post-hematopoietic stem cell transplantation from June 2019 to October 2021were reviewed. The study examined the effort of different periodontal statuses on oral complications and infections in patients during transplantation.

Results

Of 549 transplant patients studied, 363 had periodontitis. Patients with or without periodontitis showed significant differences in mean age, male proportion, and mucositis incidence during transplantation (P < 0.05). Bacteremia rates were slightly higher in patients with periodontitis, but not significant. Male proportion, age, and hospitalization duration significantly increased with advancing periodontitis stages. Only two patients experienced periodontal complications, that were effectively managed and did not interfere in the grafting process.

Conclusion

Periodontitis is prevalent in patients with hematopoietic diseases. Despite its association with oral mucositis, the occurrence of periodontal infection remains low and controllable.

Far-ultraviolet irradiation at 222 nm destroys and sterilizes the biofilms formed by periodontitis pathogens

BACKGROUND

Periodontal disease is the leading cause of tooth loss, and an association between periodontal disease and non-oral systemic diseases has been shown. Formation of biofilm by periodontal pathogens such as Fusobacterium nucleatum, Porphyromonas gingivalis, and Streptococcus mutans and their resistance to antimicrobial agents are at the root of persistent and chronic bacterial infections.

METHODS

The bactericidal effect of far-ultraviolet (F-UV) light irradiation at 222 nm on periodontal bacteria was assessed qualitatively and quantitatively. The effect of biofilm disruption by F-UV light on periodontal bacteria was examined by crystal violet staining, and the morphologic changes of the biofilm after F-UV irradiation were explored by confocal laser microscopy and scanning electron microscopy. We developed a thin fiber-type 222 nm F-UV irradiator and studied its safety and effect of reducing bacteria in rodent models.

RESULTS

F-UV light at 222 nm had a bactericidal effect on F. nucleatum, P. gingivalis, and S. mutans. Irradiation with F-UV light reduced the biofilm formed by the bacteria and sterilized them from within. Confocal laser microscopy showed a clear reduction in biofilm thickness, and scanning electron microscopy confirmed disintegration of the biofilm architecture. F-UV irradiation was less damaging to DNA and less cytotoxic than deep-ultraviolet light, and it reduced bacterial counts on the tooth surface.

CONCLUSION

F-UV irradiation has the potential to destroy biofilm and act as a bactericide against pathogenic bacteria in the biofilm.

Bioactive injectable mucoadhesive thermosensitive natural polymeric hydrogels for oral bone and periodontal regeneration

Periodontitis is an inflammation-related condition, caused by an infectious microbiome and host defense that causes damage to periodontium. The natural processes of the mouth, like saliva production and eating, significantly diminish therapeutic medication residency in the region of periodontal disease. Furthermore, the complexity and diversity of pathological mechanisms make successful periodontitis treatment challenging. As a result, developing enhanced local drug delivery technologies and logical therapy procedures provides the foundation for effective periodontitis treatment. Being biocompatible, biodegradable, and easily administered to the periodontal tissues, hydrogels have sparked substantial an intense curiosity in the discipline of periodontal therapy. The primary objective of hydrogel research has changed in recent years to intelligent thermosensitive hydrogels, that involve local adjustable sol-gel transformations and regulate medication release in reaction to temperature, we present a thorough introduction to the creation and efficient construction of new intelligent thermosensitive hydrogels for periodontal regeneration. We also address cutting-edge smart hydrogel treatment options based on periodontitis pathophysiology. Furthermore, the problems and prospective study objectives are reviewed, with a focus on establishing effective hydrogel delivery methods and prospective clinical applications.

Periodontopathogen-Related Cell Autophagy-A Double-Edged Sword

The periodontium is a highly organized ecosystem, and the imbalance between oral microorganisms and host defense leads to periodontal diseases. The periodontal pathogens, mainly Gram-negative anaerobic bacteria, colonize the periodontal niches or enter the blood circulation, resulting in periodontal tissue destruction and distal organ damage. This phenomenon links periodontitis with various systemic conditions, including cardiovascular diseases, malignant tumors, steatohepatitis, and Alzheimer's disease. Autophagy is an evolutionarily conserved cellular self-degradation process essential for eliminating internalized pathogens. Nowadays, increasing studies have been carried out in cells derived from periodontal tissues, immune system, and distant organs to investigate the relationship between periodontal pathogen infection and autophagy-related activities. On one hand, as a vital part of innate and adaptive immunity, autophagy actively participates in host resistance to periodontal bacterial infection. On the other, certain periodontal pathogens exploit autophagic vesicles or pathways to evade immune surveillance, therefore achieving survival within host cells. This review provides an overview of the autophagy process and focuses on periodontopathogen-related autophagy and their involvements in cells of different tissue origins, so as to comprehensively understand the role of autophagy in the occurrence and development of periodontal diseases and various periodontitis-associated systemic illnesses.

Effects of Oleanolic Acid Derived from Wine Pomace on Periodontopathic Bacterial Growth in Healthy Individuals: A Randomized Placebo-Controlled Study

Periodontal disease is caused by oral pathogenic bacteria and is associated with systemic disease and frailty. Therefore, its prevention is crucial in extending healthy life expectancy. This study aimed to evaluate the effect of orally administered oleanolic acid, extracted from wine pomace, on periodontopathic bacterial growth in healthy individuals. In this randomized, placebo-controlled, double-blind, parallel-group comparison study, 84 healthy adults were assigned to a placebo (n = 29), low-dose (n = 29, 9 mg oleanolic acid), or high-dose (n = 26, 27 mg oleanolic acid) groups. The number of oral bacteria in their saliva, collected before and 5 h after administration, was determined using the polymerase chain reaction-invader technique. The proportion of periodontopathic bacteria among the total oral bacteria in the saliva was calculated. Oleanolic acid significantly decreased the proportion of Porphyromonas gingivalis among the total oral bacteria in a dose-dependent manner (p = 0.005 (low-dose) and p = 0.003 (high-dose) vs. placebo, Williams' test). Moreover, high-dose oleanolic acid decreased the proportion of Tannerella forsythia (p = 0.064 vs. placebo, Williams' test). Periodontopathic bacteria are closely associated with the development and progression of periodontal disease; thus, the continuous daily intake of oleanolic acid derived from pomace may be helpful in maintaining a healthy oral microbiome by controlling the proportion of periodontopathic bacteria.

SARS-CoV-2, periodontal pathogens, and host factors: The trinity of oral post-acute sequelae of COVID-19

COVID-19 as a pan-epidemic is waning but there it is imperative to understand virus interaction with oral tissues and oral inflammatory diseases. We review periodontal disease (PD), a common inflammatory oral disease, as a driver of COVID-19 and oral post-acute-sequelae conditions (PASC). Oral PASC identifies with PD, loss of teeth, dysgeusia, xerostomia, sialolitis-sialolith, and mucositis. We contend that PD-associated oral microbial dysbiosis involving higher burden of periodontopathic bacteria provide an optimal microenvironment for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. These pathogens interact with oral epithelial cells activate molecular or biochemical pathways that promote viral adherence, entry, and persistence in the oral cavity. A repertoire of diverse molecules identifies this relationship including lipids, carbohydrates and enzymes. The S protein of SARS-CoV-2 binds to the ACE2 receptor and is activated by protease activity of host furin or TRMPSS2 that cleave S protein subunits to promote viral entry. However, PD pathogens provide additional enzymatic assistance mimicking furin and augment SARS-CoV-2 adherence by inducing viral entry receptors ACE2/TRMPSS, which are poorly expressed on oral epithelial cells. We discuss the mechanisms involving periodontopathogens and host factors that facilitate SARS-CoV-2 infection and immune resistance resulting in incomplete clearance and risk for 'long-haul' oral health issues characterising PASC. Finally, we suggest potential diagnostic markers and treatment avenues to mitigate oral PASC.

Lactobacillus rhamnosus inhibits osteoclast differentiation by suppressing the TLR2/NF-κB pathway

OBJECTIVE

This study aimed to investigate the role of ultrasonicated Lactobacillus rhamnosus extract in osteoclast differentiation and its underlying mechanism, providing new strategies for the treatment of periodontitis.

MATERIALS AND METHODS

Osteoclasts were induced using macrophage colony-stimulating factor and receptor activator for nuclear factor-κB ligand. Lactobacillus rhamnosus extracts were obtained via ultrasonic crushing and ultracentrifugation. The effects of the LGG extract on osteoclast differentiation were evaluated, and the related signaling pathways were examined using western blotting. A mouse periodontitis model was established, and Lactobacillus rhamnosus extract was injected into the gingival sulcus to evaluate the inhibitory effect of Lactobacillus rhamnosus extract on alveolar bone resorption.

RESULTS

At 50 μg/mL, Lactobacillus rhamnosus extract inhibited osteoclast differentiation with no effect on apoptosis and proliferation. This phenomenon was achieved by deactivating the NF-κB/c-Fos/NFATc1 signaling pathway through toll-like receptor 2. The in vivo results showed that the local injection of Lactobacillus rhamnosus extract suppressed osteoclast differentiation and alveolar bone resorption.

CONCLUSION

The ultrasonicated extract of Lactobacillus rhamnosus inhibited osteoclast differentiation by suppressing the activation of the NF-κB/c-Fos/NFATc1 pathway. Furthermore, it inhibited the destruction of the alveolar bone, providing a new strategy for the use of probiotics in the treatment of periodontitis.

Antibacterial activity of lysozyme-chitosan oligosaccharide conjugates on two periodontal bacteria

OBJECTIVE

This study aimed to evaluate the in vitro antibacterial effects of lysozyme-chitosan oligosaccharide conjugates (LYZOX) against Streptococcus gordonii and Porphyromonas gingivalis.

MATERIALS AND METHODS

Planktonic S. gordonii and P. gingivalis were treated with various concentrations of LYZOX for 10 min. The treated bacteria were incubated on trypticase soy agar plates, and colony-forming unit (CFU) was calculated. The antibacterial effect of LYZOX was compared with that of lysozyme, chitosan, physiological saline, and benzalkonium chloride solution. Cell morphology before and after LYZOX treatment was observed using a scanning electron microscope (SEM). The antibacterial effect of LYZOX with decanoic acid against the biofilm-like bacteria was also examined via crystal violet staining. The Kruskal-Wallis test and post hoc Dunn tests were performed to compare the difference in antibacterial activity of each treatment.

RESULTS

Bacterial CFU numbers were reduced after LYZOX treatment in a concentration-dependent manner. The reduction in CFUs was smaller for corresponding concentrations of chitosan or lysozyme alone. SEM analyses revealed bacterial cells shrank following LYZOX treatment. The combined use of LYZOX and decanoic acid yielded an even higher antibacterial effect against bacterial biofilms.

CONCLUSION

LYZOX exhibits antibacterial activity against two periodontal bacteria and may be a promising plaque control agent.

Oral health as a modifiable risk factor for cardiovascular diseases

Cardiovascular diseases (CVDs) are a leading cause of morbidity and mortality worldwide with a high socioeconomic burden. Increasing evidence supports a convincing connection with increased cardiovascular risk of periodontal diseases (PD), a group of widespread, debilitating, and costly dysbiotic relapsing-remitting inflammatory diseases of the tissues supporting the teeth. Herein, we ensembled the best available evidence on the connection between CVDs and PD to review the recently emerging concept of the latter as a non-traditional risk factor for CVDs. We focused on oral dysbiosis, inflammation-associated molecular and cellular mechanisms, and epigenetic changes as potential causative links between PD and CVDs. The available evidence on the effects of periodontal treatment on cardiovascular risk factors and diseases was also described.

Antibacterial activity of corydalis saxicola bunting total alkaloids against Porphyromonas gingivalis in vitro

Aim: To investigate the antibacterial effects of Corydalis Saxicola bunting total alkaloid (CSBTA) on Porphyromonas gingivalis. Methods: SEM, chemical staining, RT-qPCR and ELISA were used to detect effects of CSBTA on P. gingivalis. Results: CSBTA treatment caused shrinkage and rupture of P. gingivalis morphology, decreased biofilm density and live bacteria in biofilm, as well as reduced mRNA expression of virulence genes hagA, hagB, kgp, rgpA and rgpB of P. gingivalis. Furthermore, NOK cells induced by CSBTA-treated P. gingivalis exhibited lower IL-6 and TNF-α expression levels. Conclusion: CSBTA is able to kill free P. gingivalis, disrupt the biofilm and weaken the pathogenicity of P. gingivalis. It has the potential to be developed as a drug against P. gingivalis infection.

Tooth Loss and Chronic Pain: A Population-based Analysis of the National Health and Nutrition Examination Survey

Poor oral health conditions in adults are associated with chronic pain. A nationwide cross-sectional study was conducted to investigate the link between tooth loss and chronic pain. The study involved 8,662 participants from the National Health and Nutrition Examination Survey. Tooth count was categorized into 4 groups, and chronic pain was defined as persistent pain lasting over 3 months despite treatment. Location of the chronic pain, demographics, comorbidities, lifestyle determinants, and dietary intake were retrieved. Univariate and multivariate logistic regression were used to explore cross-sectional associations between tooth count and chronic pain. Compared to participants with more than 20 teeth, those with severe tooth loss presented greater odds of chronic pain (adjusted odds ratio [aOR] = 2.111, 95% confidence intervals (CI) = 1.213-3.676 for patients with 1-8 teeth). Edentulous participants presented with significantly higher odds of chronic pain in the lower extremities (78.4%) and buttocks (49.5%). In the multivariate model, apart from rheumatic arthritis (aOR = 4.004, 95% CI = 2.766-5.798), variables of higher chronic pain included smoking (aOR = 1.518, 95% CI = 1.228-1.878), and hypertension (aOR = 1.463, 95% CI = 1.013-2.112). On the contrary, being Mexican American (aOR = .603, 95% CI = .414-.880) was associated with lower odds of chronic pain. The findings suggested a significant link between chronic pain and tooth loss, independent of ethnicity, lifestyle determinants, and immune-mediated inflammatory diseases including rheumatoid arthritis. PERSPECTIVE: A U.S. nationwide study examined tooth loss and chronic pain. Those with severe tooth loss had increased odds of chronic pain. Edentulous individuals presented higher odds of pain in lower extremities and buttocks. This study highlighted the link between tooth loss and chronic pain, independent of comorbidities and lifestyle factors.

Effect of prolonged hospitalization on the maintenance of oral health: A self-report survey

OBJECTIVES

This study aims to evaluate the effect of prolonged hospitalization on the maintenance of dental health and to assess the nursing staff's approach to addressing these concerns.

METHODS

A survey questionnaire explored changes in the routine dental care of patients hospitalized for over a month. The involvement of nursing staff in addressing dental care was also evaluated.

RESULTS

Fifty adult patients aged 18-89 years (mean age 62.4 ± 20.54 years), 27 (54%) males, completed the survey. During hospitalization (mean 58.59 ± 38.63 days) 26% and 18%, increased consumption of sweets and sugary beverages, between meals, respectively; 26% and 20% of the patients reduced the frequency of tooth brushing in the morning and in the evening, respectively, and 42.2% of them, reduced the quality of their toothbrushing during hospitalization. Nevertheless, 95.9% and 93.9% of them were never instructed during hospitalization to limit their consumption of sweets and sugary beverages and 83.3% and 62.5% of them had never been reminded or offered assistance during hospitalization in performing toothbrushing, respectively. The lower frequency of morning toothbrushing was significantly correlated with a lack of nurses' assistance (p = 0.004). In contrast, 62.6% reported they were reminded every day to shower. Patients in the rehabilitation and geriatrics departments reported a greater need for a brush/toothpaste (p < 0.0001) and assistance in toothbrushing (p < 0.0001).

CONCLUSIONS

Prolonged hospitalization leads to significant deterioration in inpatients' dental health maintenance. Raising awareness among nurses regarding their inpatient's oral health maintenance is warranted. Providing patients with toothbrushes, toothpaste and educational materials upon hospitalization is recommended.

Comparative analysis of microbial composition and functional characteristics in dental plaque and saliva of oral cancer patients

BACKGROUND

The oral cavity is home to various ecological niches, each with its own unique microbial composition. Understanding the microbial communities and gene composition in different ecological niches within the oral cavity of oral cancer (OC) patients is crucial for determining how these microbial populations contribute to disease progression.

METHODS

In this study, saliva and dental plaque samples were collected from patients with OC. Metagenomic sequencing was employed to analyze the microbial community classification and functional composition of the different sample groups.

RESULTS

The results of the study revealed significant differences in both the function and classification of microbial communities between saliva and dental plaque samples. The diversity of microbial species in saliva was found to be higher compared to  that in plaque samples. Notably, Actinobacteria were enriched in the dental plaque of OC patients. Furthermore, the study identified several inter-group differential marker species, including Prevotella intermedia, Haemophilus parahaemolyticus, Actinomyces radius, Corynebacterium matruchitii, and Veillonella atypica. Additionally, 1,353 differential genes were annotated into 23 functional pathways. Interestingly, a significant correlation was observed between differentially labeled species and Herpes simplex virus 1 (HSV-1) infection, which may be related to the occurrence and development of cancer.

CONCLUSIONS

Significant differences in the microbial and genetic composition of saliva and dental plaque samples were observed in OC patients. Furthermore, pathogenic bacteria associated with oral diseases were predominantly enriched in saliva. The identification of inter-group differential biomarkers and pathways provide insights into the relationship between oral microbiota and the occurrence and development of OC.

Migraine and the microbiota. Can probiotics be beneficial in its prevention? - a narrative review

Migraine is a recurrent disease of the central nervous system that affects an increasing number of people worldwide causing a continuous increase in the costs of treatment. The mechanisms underlying migraine are still unclear but recent reports show that people with migraine may have an altered composition of the intestinal microbiota. It is well established that the gut-brain axis is involved in many neurological diseases, and probiotic supplementation may be an interesting treatment option for these conditions. This review collects data on the gastrointestinal and oral microbiota in people suffering from migraine and the use of probiotics as a novel therapeutic approach in its treatment.

Frankincense (Boswellia serrata) Extract Effects on Growth and Biofilm Formation of Porphyromonas gingivalis, and Its Intracellular Infection in Human Gingival Epithelial Cells

Frankincense is produced by Boswellia trees, which can be found throughout the Middle East and parts of Africa and Asia. Boswellia serrata extract has been shown to have anti-cancer, anti-inflammatory, and antimicrobial effects. Periodontitis is an oral chronic inflammatory disease that affects nearly half of the US population. We investigated the antimicrobial effects of B. serrata extract on two oral pathogens associated with periodontitis. Using the minimum inhibitory concentration and crystal violet staining methods, we demonstrated that Porphyromonas gingivalis growth and biofilm formation were impaired by treatment with B. serrata extracts. However, the effects on Fusobacterium nucleatum growth and biofilm formation were not significant. Using quantification of colony-forming units and microscopy techniques, we also showed that concentrations of B. serrata that were not toxic for host cells decreased intracellular P. gingivalis infection in human gingival epithelial cells. Our results show antimicrobial activity of a natural product extracted from Boswellia trees (B. serrata) against periodontopathogens. Thus, B. serrata has the potential for preventing and/or treating periodontal diseases. Future studies will identify the molecular components of B. serrata extracts responsible for the beneficial effects.

Periodontitis exacerbates pulmonary hypertension by promoting IFNγ+ T cell infiltration in mice

Uncovering the risk factors of pulmonary hypertension and its mechanisms is crucial for the prevention and treatment of the disease. In the current study, we showed that experimental periodontitis, which was established by ligation of molars followed by orally smearing subgingival plaques from patients with periodontitis, exacerbated hypoxia-induced pulmonary hypertension in mice. Mechanistically, periodontitis dysregulated the pulmonary microbiota by promoting ectopic colonization and enrichment of oral bacteria in the lungs, contributing to pulmonary infiltration of interferon gamma positive (IFNγ+) T cells and aggravating the progression of pulmonary hypertension. In addition, we identified Prevotella zoogleoformans as the critical periodontitis-associated bacterium driving the exacerbation of pulmonary hypertension by periodontitis, and the exacerbation was potently ameliorated by both cervical lymph node excision and IFNγ neutralizing antibodies. Our study suggests a proof of concept that the combined prevention and treatment of periodontitis and pulmonary hypertension are necessary.

Oral and gut microbial profiling in periodontitis and Parkinson's disease

Objectives

We tested the hypothesis that Parkinson's disease (PA) alters the periodontitis-associated oral microbiome.

Method

Patients with periodontitis with Parkinson's disease (PA+P) and without PA (P) and systemically and periodontally healthy individuals (HC) were enrolled. Clinical, periodontal and neurological parameters were recorded. The severity of PA motor functions was measured. Unstimulated saliva samples and stool samples were collected. Next-generation sequencing of 16S ribosomal RNA (V1-V3 regions) was performed.

Results

PA patients had mild-to-moderate motor dysfunction and comparable plaque scores as those without, indicating that oral hygiene was efficient in the PA+P group. In saliva, there were statistically significant differences in beta diversity between HC and PA+P (p = 0.001), HC and P (p = 0.001), and P and PA+P (p = 0.028). The microbial profiles of saliva and fecal samples were distinct. Mycoplasma faucium, Tannerella forsythia, Parvimonas micra, and Saccharibacteria (TM7) were increased in P; Prevotella pallens, Prevotella melaninogenica, Neisseria multispecies were more abundant in PA+P group, Ruthenibacterium lactatiformans, Dialister succinatiphilus, Butyrivibrio crossotus and Alloprevotella tannerae were detected in fecal samples in P groups compared to healthy controls.

Conclusions

No significant differences were detected between Parkinson's and non-Parkinson's gut microbiomes, suggesting that Parkinson's disease modifies the oral microbiome in periodontitis subjects independent of the gut microbiome.