Incidence of bacteremia after chewing, tooth brushing and scaling in individuals with periodontal inflammation

Pyogenic spondylodiscitis from oral odontogenic origins: a frequently overlooked entity

BACKGROUND CONTEXT

Primary spondylodiscitis occurs through the hematogenous spread of a pathogen entering the body via a point of entry. The infection's origin often remains unclear. During dental procedures or through minor traumas, oral bacteria can enter the bloodstream and disseminate throughout the body.

PURPOSE

This study's objective was to further investigate the role of odontogenic (ie, teeth-related) causes of spondylodiscitis, especially in cases where another infective focus could not be identified initially.

DESIGN

Retrospective analysis.

PATIENT SAMPLE

In a cohort of 340 consecutive patients with primary spondylodiscitis treated at a Level I Spine Center from January 1, 2018 to December 31, 2022, those with oral bacteria in blood cultures or disc tissue samples and available orthopantomograms (OPG, ie, panoramic X-ray of the teeth) were retrospectively reevaluated for odontogenic origins. Patients with secondary spondylodiscitis from a previous operation (< 3 months) in the same segment were excluded.

OUTCOME MEASURES

Radiological features indicating an infectious dental focus included apical radiolucency of the tooth, impacted teeth, residual roots, and vertical or cup-shaped bone loss.

METHODS

Patients' medical records, imaging data, laboratory, microbiological and histopathological findings, and surgical reports were analyzed. The term oral bacteria refers to the whole microbiome of the oral cavity. Periodontal bacteria are bacterial species implicated in periodontal diseases. For further classification, periodontal bacteria were assigned to one of five complexes previously described.

RESULTS

The most frequent infective source was an infection of the major joints of the extremities (14.1%), followed by ulcers of the extremities (10.3%) and urosepsis (10.0%). An odontogenic origin was initially identified in 8.9%. In 33.1% of cases, the source of infection was not found. Oral bacteria were found in 38 cases (13.3%) of 286 (ie, all cases with a positive pathogen detection). Six of these had an identified focus of the throat, and six had an initially clear dental focus. Of the remaining 26 cases, OPG was available for 14. Reevaluation of OPG revealed an odontogenic focus in 9 out of 14 cases (64.3%). Two of these cases had a concomitant infective focus, while in 7 cases, no infective source was initially found.

CONCLUSION

An odontogenic origin for spondylodiscitis was more prevalent than initially presumed, particularly in patients where no source was identified at first sight. We therefore recommend a thorough diagnostic dental work-up as a standard procedure for patients with primary spondylodiscitis.

Cross-sectional associations between vitamin D status and periodontitis in adults in Northern Norway: The Tromsø Study 2015-2016

BACKGROUND

Vitamin D is involved in the immune system by regulating inflammatory processes. Over the recent decades, there has been an increase in studies investigating the potential influence of vitamin D status on inflammatory diseases and conditions. However, research on the link between vitamin D and periodontitis remains scarce. Hence, we aimed to examine the relationship between serum 25(OH)D levels and periodontitis in an adult population in Northern Norway.

METHODS

The study was based on cross-sectional data from a population-based study: the seventh Tromsø study, conducted in 2015 - 2016. Eligible participants were adults ( ≥ 40 years old) who had both a valid periodontal diagnosis and data on serum 25(OH)D levels, giving a total study sample of n = 3,693 participants (51.4% women). Periodontitis was defined according to the 2017 AAP/EFP classification system. Two groups were compared: no-periodontitis/stage I periodontitis versus stages II-III/IV periodontitis. Using a bivariate logistic regression analysis, the association between these two groups and serum 25(OH)D was tested, controlling for age, sex, smoking, toothbrushing frequency, and socioeconomic status. Periodontal pockets of ≥ 5 mm and their association with serum 25(OH)D were also tested.

RESULTS

About 89% were classified as having periodontitis, and 51.6% had stages II-III/IV periodontitis. About 4% of the participants were at deficient levels of serum 25(OH)D (< 30 nmol/L). Levels of serum 25(OH)D of < 30 nmol/L were associated with periodontitis stage II-III/IV (odds ratio [OR] 1.53, 95% confidence interval [CI]: 1.03-2.28). Stratified by when the season serum 25(OH)D was measured (March-September vs October-February), the summer strata was significantly associated with periodontitis II-III/IV (30-50 nmol/L = OR 1.31, 95% CI:1.05-1.63, p = 0.018). Vitamin D deficiency and insufficiency were associated with having at least one periodontal pocket of ≥ 5 mm (< 30 nmol/L = 1.78, 95% CI:1.22-2.60, p = 0.003: 30-50 nmol/L = OR was 1.23, 95% CI:1.03-1.47, p = 0.020, respectively).

CONCLUSION

In this Norwegian adult population, blood 25-hydroxy vitamin D [25(OH)D] levels were associated to periodontitis stage II-III/IV and a periodontal pocket depth of ≥ 5 mm.

Bridging oral and systemic health: exploring pathogenesis, biomarkers, and diagnostic innovations in periodontal disease

PURPOSE

This narrative review explores the multifaceted links between periodontal diseases (gingivitis and periodontitis) and systemic health conditions, including cardiovascular disease, diabetes, adverse pregnancy outcomes, Alzheimer's disease, cancers, rheumatoid arthritis, and respiratory infections. It aims to synthesize evidence on how local oral infections exert systemic effects and evaluate the potential of diagnostic technologies to monitor these interactions.

METHODS

This narrative review synthesizes current scientific literature on periodontal disease pathogenesis, focusing on key pathogens (e.g., Porphyromonas gingivalis, Fusobacterium nucleatum) and their roles in driving local and systemic inflammation via virulence factors and microbial dysbiosis. It examines biomarker-based diagnostic approaches (e.g., IL-1β, TNF-α, microbial DNA) in saliva, blood, and gingival crevicular fluid (GCF) and evaluates current and emerging diagnostic tools (e.g., ELISA, PCR, lateral flow assays, biosensors, microfluidics).

RESULTS

The review highlights that periodontal pathogens contribute to systemic disease through complex mechanisms including persistent inflammation (driven by cytokines like IL-1β, TNF-α), endotoxemia (via LPS, noting pathogen-specific structural variations impacting immune response), molecular mimicry, and immune modulation. Current diagnostic methods provide valuable information but often face limitations in speed, portability, and multiplexing capability needed for comprehensive point-of-care assessment. Emerging technologies, particularly multiplex platforms integrating biosensors or microfluidics, demonstrate significant potential for rapid, user-friendly analysis of multiple biomarkers, facilitating earlier detection and personalized risk stratification, especially in high-risk populations.

CONCLUSION

Periodontal diseases significantly impact systemic health via intricate microbial and inflammatory pathways. The complexity of these interactions necessitates moving beyond conventional diagnostics towards integrated, advanced technologies. Implementing rapid, multiplex biomarker detection platforms within a multidisciplinary healthcare framework holds the potential to revolutionize early detection of linked conditions, improve personalized management strategies, and ultimately reduce the systemic burden of periodontal disease.

Bacterial translocation signatures and subgingival microbiome in individuals with periodontitis

OBJECTIVES

To determine bacterial blood translocation signatures and their association with the subgingival microbiota in individuals with and without periodontitis.

MATERIALS AND METHODS

Cross-sectional study. DNA was extracted from blood and subgingival samples of individuals with periodontitis (n = 21) and control volunteers (n = 24). Subgingival microbiota was explored by 16 S rRNA gene sequencing. Detection frequency and loads of total bacteria, Porphyromonas gingivalis (Pg), Porphyromonas endodontalis (Pe) and Fusobacterium nucleatum (Fn) were determined in all samples using quantitative polymerase chain reaction (qPCR). The statistical analysis was performed using STATA 16.

RESULTS

Subgingival samples from individuals with periodontitis presented higher relative abundance of Prevotella intermedia, F. nucleatum subsp. vincentii, Treponema sp. HMT 237, Alloprevotella tannerae, Filifactor alocis, Pg, Treponema denticola and Pe, and higher loads of total bacteria, Pg, Pe and Fn, compared to the control group (p < 0.001). While Pg and Fn were not detected in blood, Pe was detected in 95% of individuals with periodontitis and 83% of the control ones (p = 0.205), with higher loads in blood samples from periodontitis (p = 0.034). No significant correlation was found between subgingival bacterial loads and blood loads of Pe in periodontitis and control groups (p > 0.05).

CONCLUSIONS

Individuals with periodontitis presented higher relative abundance and loads of periodontal bacteria in subgingival samples and higher Pe loads in blood samples, although further research is needed to understand the correlation between subgingival and blood bacterial loads.

CLINICAL RELEVANCE

The present study showed higher loads of Pe in the blood of individuals with periodontitis, suggesting potential extraoral dissemination and a linking mechanism with several systemic diseases.

Oral Fusobacterium nucleatum exacerbates ulcerative colitis via the oral-gut axis: mechanisms and therapeutic implications

Background

Fusobacterium nucleatum (F. nucleatum) is an anaerobic bacterium known for its association with periodontal disease and oral infections. It has been implicated in the development of gastrointestinal diseases such as inflammatory bowel disease and colorectal cancer. Ulcerative colitis (UC), which is characterized by chronic inflammation of the colon, is a condition of unknown etiology with a rising incidence rate, significantly affecting the quality of life for patients. The increased intestinal permeability during UC may facilitate the adherence or invasion of F. nucleatum into the damaged intestinal barrier, leading to exacerbated inflammation.

Methods

This article introduces the concept of the oral-gut axis, reviewing existing literature to analyze the role of F. nucleatum in the pathogenesis of UC and exploring its potential pathogenic mechanisms. It also summarizes the latest advances in treating patients with UC who have F. nucleatum and looks forward to prospective therapeutic strategies and the translational prospects of F. nucleatum within the oral-gut axis.

Results

F. nucleatum may be a key player in the pathogenesis of UC, likely due to its invasiveness during periods of increased intestinal permeability. The paper also discusses innovative approaches for the prevention and management of UC exacerbated by F. nucleatum, paving the way for more effective treatment of UC.

Conclusion

The review offers new insights into the complex relationship between the oral microbiome and intestinal diseases, enhancing our understanding of their dynamic interactions. There is a paucity of literature on therapeutic approaches, indicating a need for further clinical research.

Fatty Acid Binding Protein 4 Could Be a Linking Biomarker Between Periodontitis and Systemic Diseases

Background/Objectives: This study aims to investigate the relationship between serum fatty acid-binding protein 4 (FABP4) levels and the severity of periodontitis in systemically healthy individuals. Additionally, the study examines whether non-surgical periodontal treatment can reduce FABP4 levels, establishing its potential as a biomarker linking periodontitis to systemic diseases. Methods: A total of 89 participants with stage I, II, or III periodontitis were recruited, excluding individuals with systemic diseases. Clinical parameters such as clinical attachment level (CAL), probing depth (PD), and gingival index (GI) were recorded. Serum FABP4 levels and Porphyromonas gingivalis (P. gingivalis) antibody titers were measured before and after periodontal treatment using ELISA kits. Statistical analysis included t-tests, correlation analysis, and multiple linear regression to assess changes in FABP4 levels and their association with clinical parameters. Results: FABP4 and P. gingivalis antibody titers significantly increased with the severity of periodontitis (p < 0.001). After non-surgical periodontal treatment, FABP4 levels significantly decreased across all stages of periodontitis. Moderate positive correlations were observed between FABP4 and CAL, PD, GI, and P. gingivalis antibody titers (p < 0.05). Multiple linear regression showed that FABP4 levels increased significantly with the progression of periodontitis, independent of age and sex. Conclusions: The study indicates that FABP4 is a potential biomarker for linking periodontitis to systemic conditions such as cardiovascular diseases and diabetes. Non-surgical periodontal treatment reduced FABP4 levels, potentially contributing to the improvement of systemic conditions associated with elevated FABP4. Further research should explore the role of FABP4 in patients with periodontitis and systemic diseases to strengthen its clinical relevance.

Broadened substrate specificity of bacterial dipeptidyl-peptidase 7 enables release of half of all dipeptide combinations from peptide N-termini

Dipeptide production mediated by dipeptidyl-peptidase (DPP)4, DPP5, DPP7, and DPP11 plays a crucial role in growth of Porphyromonas gingivalis, a periodontopathic asaccharolytic bacterium. Given the particular P1-position specificity of DPPs, it has been speculated that DPP5 or DPP7 might be responsible for degrading refractory P1 amino acids, i.e., neutral (Thr, His, Gly, Ser, Gln) and hydrophilic (Asn) residues. The present results identified DPP7 as an entity that processes these residues, thus ensuring complete production of nutritional dipeptides in the bacterium. Activity enhancement by the P1' residue was observed in DPP7, as well as DPP4 and DPP5. Toward the refractory P1 residues, DPP7 uniquely hydrolyzed HX|LD-MCA (X = His, Gln, or Asn) and their hydrolysis was most significantly suppressed in dpp7 gene-disrupted cells. Additionally, hydrophobic P2 residue significantly enhanced DPP7 activity toward these substrates. The findings propose a comprehensive 20 P1 × 20 P2 amino acid matrix showing the coordination of four DPPs to achieve complete dipeptide production along with subsidiary peptidases. The present finding of a broad substrate specificity that DPP7 accounts for releasing 48 % (192/400) of N-terminal dipeptides could implicate its potential role in linking periodontopathic disease to related systemic disorders.

Smoking Impacts Alzheimer's Disease Progression Through Oral Microbiota Modulation

Alzheimer's disease (AD) is an important public health challenge with a limited understanding of its pathogenesis. Smoking is a significant modifiable risk factor for AD progression, and its specific mechanism is often interpreted from a toxicological perspective. However, microbial infections also contribute to AD, with oral microbiota playing a crucial role in its progression. Notably, smoking alters the ecological structure and pathogenicity of the oral microbiota. Currently, there is no systematic review or summary of the relationship between these three factors; thus, understanding this association can help in the development of new treatments. This review summarizes the connections between smoking, AD, and oral microbiota from existing research. It also explores how smoking affects the occurrence and development of AD through oral microbiota, and examines treatments for oral microbiota that delay the progression of AD. Furthermore, this review emphasizes the potential of the oral microbiota to act as a biomarker for AD. Finally, it considers the feasibility of probiotics and oral antibacterial therapy to expand treatment methods for AD.

From gingiva to multiple organs in mice: The trace of Porphyromonas gingivalis via in vivo imaging

Background/purpose

Periodontitis is associated with systemic health. One of the underlying mechanisms is the translocation of periodontal pathogens, among which Porphyromonas gingivalis (Pg) is the most common. Here, we aimed to illustrate the biodistribution and dynamics of Pg from gingiva to multiple organs through blood circulation.

Materials and methods

Pg tagged by Cyanine 7 (Cy7-Pg) was injected into the gingiva of healthy and periodontitis mice. In vivo imaging system (IVIS) was applied to monitor the distribution of Cy7-Pg in multiple organs which were isolated at serial timepoints. Polymerase chain reaction (PCR) was conducted to determine the Pg DNA copies in the gingiva, blood and organs. Cy7-Pg in the gingiva and organs was also confirmed by frozen section staining. Furthermore, to figure out whether the bacteremia derived from oral-gut axis, mice received gavage of Cy7-Pg. Then the blood and organ samples were detected in the similar way as above.

Results

Intra-gingival injection induced larger amounts of Cy7-Pg accumulating in the gingiva of periodontitis mice (P < 0.05) as confirmed by above three methods. Twenty minutes after injection, Pg DNA copies in the blood of periodontitis group were 36.3-fold higher than healthy group (P < 0.05). IVIS results, combined with PCR and frozen sections, demonstrated periodontitis induced longer retention with higher amounts of Cy7-Pg in the periodontitis group. Pg was enriched more significantly in the liver for the longer duration than the kidney and pancreas.

Conclusion

Our study showed Pg, which accumulated in the gingiva, could translocate through blood circulation to multiple organs with varied duration and amounts.

Periodontal disease and cirrhosis: current concepts and future prospects

Periodontal diseases are prevalent among the general population and are associated with several systemic conditions, such as chronic kidney disease and type 2 diabetes mellitus. Chronic liver disease and cirrhosis have also been linked with periodontal disease, an association with complex underlying mechanisms, and with potential prognostic implications. Multiple factors can explain this relevant association, including nutritional factors, alcohol consumption, disruption of the oral-gut-liver axis and associated dysbiosis. Additionally, patients with liver disease have been observed to exhibit poorer oral hygiene practices compared with the general population, potentially predisposing them to the development of periodontal disease. Therefore, it is recommended that all patients with liver disease undergo screening and subsequent treatment for periodontal disease. Treatment of periodontal disease in patients with cirrhosis may help reduce liver-derived inflammatory damage, with recent research indicating a potential benefit in terms of reduced mortality. However, further studies on periodontal disease treatment in patients with liver disease are still warranted to determine optimal management strategies. This narrative review describes current concepts on the association between periodontal disease and chronic liver disease.

Association between oral microbiome diversity and all-cause mortality: a longitudinal study of NHANES, 2009-2012

OBJECTIVE

The study investigates the association between oral microbiome diversity and all-cause mortality.

DESIGN

Population-based cohort study.

SETTING

US National Health and Nutrition Examination Survey (2009-2010 and 2011-2012).

PARTICIPANTS

A total of 8224 participants who had valid data on the oral microbiome diversity and survival through 31 December 2019 were included in this study.

PRIMARY AND SECONDARY OUTCOME MEASURES

Oral microbiome diversity was measured using the observed number of amplicon sequence variant (ASV) and grouped into quartiles. Cox proportional hazards regression models were used to estimate the HR and 95% CI for all-cause mortality according to the quartiles of ASV number, adjusted for potential confounders.

RESULTS

Among the 8224 participants (mean (SD) age: 42.0 (15.1) years; 49.9% male; 37.2% white, 23.8% black, 27.2% Hispanic and 11.8% other race/ethnicity), the median follow-up time was 108 months (IQR, 95-120 months) and 429 (5.2%) deaths were identified. Participants with a higher ASV number were more likely to be poor, non-Hispanic black or Hispanic, uninsured and current smokers, more likely to have poor self-rated oral health and periodontitis and less likely to use dental floss. However, compared with the lowest quartile of the ASV number, a suggestive association was observed for the second quartile (HR=0.80, 95% CI: 0.60 to 1.08), a significant reduction in all-cause mortality was observed for the third (HR=0.55, 95% CI: 0.37 to 0.82) and the fourth (HR=0.58, 95% CI: 0.38 to 0.89) quartile. The dose-response association for all-cause mortality risk was curvilinear; the protective association plateaued when the number of ASVs was larger than 120.

CONCLUSION

Despite being linked to greater socioeconomic disadvantages and poorer oral health, higher oral microbiome diversity was significantly associated with a substantial reduction in all-cause mortality.

Oral Pathogens' Substantial Burden on Cancer, Cardiovascular Diseases, Alzheimer's, Diabetes, and Other Systemic Diseases: A Public Health Crisis-A Comprehensive Review

This review synthesizes the findings from 252 studies to explore the relationship between the oral pathogens associated with periodontitis, dental caries, and systemic diseases. Individuals with oral diseases, such as periodontitis, are between 1.7 and 7.5 times (average 3.3 times) more likely to develop systemic diseases or suffer adverse pregnancy outcomes, underscoring the critical connection between dental and overall health. Oral conditions such as periodontitis and dental caries represent a significant health burden, affecting 26-47% of Americans. The most important oral pathogens, ranked by publication frequency, include the herpes virus, C. albicans, S. mutans, P. gingivalis, F. nucleatum, A. actinomycetemcomitans, P. intermedia, T. denticola, and T. forsythia. The systemic diseases and disorders linked to oral infections, ranked similarly, include cancer, respiratory, liver, bowel, fever, kidney, complications in pregnancy, cardiovascular bacteremia, diabetes, arthritis, autoimmune, bladder, dementia, lupus, and Alzheimer's diseases. Evidence supports the efficacy of dental and periodontal treatments in eliminating oral infections and reducing the severity of systemic diseases. The substantial burden that oral pathogens have on cancer, cardiovascular diseases, Alzheimer's, diabetes, and other systemic diseases poses a significant public health crisis.

Assessment of Total Antioxidant Capacity and Malondialdehyde Levels in Obese Patients With Periodontitis

Background and objectives Obesity is increasingly recognized as a serious chronic health issue worldwide. Numerous studies have highlighted its association with periodontal disease. Both obesity and periodontal disease may be connected through oxidative stress. The purpose of this study is to determine whether periodontal problems are linked to obese people's greater vulnerability to oxidative stress. Methods A total of 120 individuals of both sexes (69 females and 51 males), with mean ages of 37.8 ± 9 years, were randomly assigned to one of three groups in a case-control study: 40 were in the control group, 40 were in the obese without periodontitis group, and 40 were in the obese with periodontitis group. The serum of the three groups was then evaluated for biochemical markers (total antioxidant capacity (TAC), malondialdehyde (MDA)) and a clinical periodontal parameter (clinical attachment level, CAL). Results The findings indicated that 30.7% of men and 41.6% of women participated in the study. Within each group, there was a significant difference (p < 0.001) in TAC and MDA levels between the obese and control groups, as well as between those with and without periodontitis. The obese group without periodontitis had a substantially larger mean waist circumference (93 ± 11.9) than the control group (86.0 ± 7.8), and the differences were statistically significant (p < 0.001). Conclusion Anthropometric and demographic measurements revealed no significant differences between obese individuals with periodontitis and those without it. Our results suggest that, in obese individuals, the onset of oxidative stress and reduced antioxidant capacity may act as a pathophysiological link to periodontitis.

The Oral Microbiota, Microbial Metabolites, and Immuno-Inflammatory Mechanisms in Cardiovascular Disease

Cardiovascular diseases (CVDs) remain a leading cause of global morbidity and mortality. Recent advancements in high-throughput omics techniques have enhanced our understanding of the human microbiome's role in the development of CVDs. Although the relationship between the gut microbiome and CVDs has attracted considerable research attention and has been rapidly evolving in recent years, the role of the oral microbiome remains less understood, with most prior studies focusing on periodontitis-related pathogens. In this review, we summarized previously reported associations between the oral microbiome and CVD, highlighting known CVD-associated taxa such as Porphyromonas gingivalis, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans. We also discussed the interactions between the oral and gut microbes. The potential mechanisms by which the oral microbiota can influence CVD development include oral and systemic inflammation, immune responses, cytokine release, translocation of oral bacteria into the bloodstream, and the impact of microbial-related products such as microbial metabolites (e.g., short-chain fatty acids [SCFAs], trimethylamine oxide [TMAO], hydrogen sulfide [H2S], nitric oxide [NO]) and specific toxins (e.g., lipopolysaccharide [LPS], leukotoxin [LtxA]). The processes driven by these mechanisms may contribute to atherosclerosis, endothelial dysfunction, and other cardiovascular pathologies. Integrated multi-omics methodologies, along with large-scale longitudinal population studies and intervention studies, will facilitate a deeper understanding of the metabolic and functional roles of the oral microbiome in cardiovascular health. This fundamental knowledge will support the development of targeted interventions and effective therapies to prevent or reduce the progression from cardiovascular risk to clinical CVD events.

Bite-sized immunology; damage and microbes educating immunity at the gingiva

Immune cells residing at the gingiva experience diverse and unique signals, tailoring their functions to enable them to appropriately respond to immunological challenges and maintain tissue integrity. The gingiva, defined as the mucosal barrier that surrounds and supports the teeth, is the only barrier site completely transected by a hard structure, the tooth. The tissue is damaged in early life during tooth eruption and chronically throughout life by the process of mastication. This occurs alongside challenges typical of barrier sites, including exposure to invading pathogens, the local commensal microbial community and environmental antigens. This review will focus on the immune network safeguarding gingival integrity, which is far less understood than that resident at other barrier sites. A detailed understanding of the gingiva-resident immune network is vital as it is the site of the inflammatory disease periodontitis, the most common chronic inflammatory condition in humans which has well-known detrimental systemic effects. Furthering our understanding of how the immune populations within the gingiva develop, are tailored in health, and how this is dysregulated in disease would further the development of effective therapies for periodontitis.

Balancing the Oral-Gut-Brain Axis with Diet

Background: The oral microbiota is the second largest microbial community in humans. It contributes considerably to microbial diversity and health effects, much like the gut microbiota. Despite physical and chemical barriers separating the oral cavity from the gastrointestinal tract, bidirectional microbial transmission occurs between the two regions, influencing overall host health. Method: This review explores the intricate interplay of the oral-gut-brain axis, highlighting the pivotal role of the oral microbiota in systemic health and ageing, and how it can be influenced by diet. Results: Recent research suggests a relationship between oral diseases, such as periodontitis, and gastrointestinal problems, highlighting the broader significance of the oral-gut axis in systemic diseases, as well as the oral-gut-brain axis in neurological disorders and mental health. Diet influences microbial diversity in the oral cavity and the gut. While certain diets/dietary components improve both gut and oral health, others, such as fermentable carbohydrates, can promote oral pathogens while boosting gut health. Conclusions: Understanding these dynamics is key for promoting a healthy oral-gut-brain axis through dietary interventions that support microbial diversity and mitigate age-related health risks.

Could the periodontal therapy improve the cardiologic patient health? A narrative review

BACKGROUND

Cardiovascular diseases (CVD) is the major cause of mortality globally, with increasing evidence suggesting a link between periodontitis, and CVD. This study aims to explore the association between periodontitis and CVD, and the impact of periodontal therapy on cardiovascular health.

METHODS

This review synthesized findings from preclinical and clinical studies, without publication year restrictions, examining periodontitis and CVD through various lenses. Scientific databases were inspected with keywords related to periodontitis and CVD.

RESULTS

The review identifies a substantial association between periodontitis and an increased risk of several CVD, supported by both epidemiological and interventional studies. Results suggest the complexity of the relationship, influenced by factors like the severity of periodontitis and the presence of other systemic conditions. Clinical data indicates that periodontal therapy, particularly non-surgical periodontal therapy, may reduce systemic inflammatory markers and thus may play a role in the primary and secondary prevention of CVD events, highlighting the potential of periodontal therapy to not only maintain oral health but also to modulate cardiovascular risk factors.

CONCLUSIONS

Current evidence supports a significant association between periodontitis and increased cardiovascular risk, promoting integrated healthcare approaches that consider oral health as a key-component of cardiovascular care and wellbeing.

The PerioGene North Study Uncovers Serum Proteins Related to Periodontitis

The sequalae of periodontitis include irreversible degradation of tooth-supporting structures and circulatory spread of inflammatory mediators. However, the serum protein profile in periodontitis is not well described, which is partly attributable to the limited number of studies based on large and well-characterized periodontitis cohorts. This study aims to identify novel, circulating inflammation-related proteins associated with periodontitis within the PerioGene North case-control study, which includes 478 cases with severe periodontitis and 509 periodontally healthy controls. The serum concentrations of high-sensitivity C-reactive protein (hs-CRP) and a panel of 45 inflammation-related proteins were analyzed using targeted proteomics. A distinguishable serum protein profile was evident in periodontitis cases. The protein pattern could separate cases from controls with a sensitivity of 0.81 and specificity of 0.81 (area under the curve = 0.87). Adjusted levels for hs-CRP and 24 of the 45 proteins were different between cases and controls. High levels of hs-CRP and matrix metalloproteinase-12, and low levels of epidermal growth factor (EGF) and oxidized low-density lipoprotein receptor 1 (OLR-1) were detected among the cases. Furthermore, the levels of C-C motif chemokine-19, granulocyte colony-stimulating factor-3 (CSF-3), interleukin-7 (IL-7), and hs-CRP were significantly higher in cases with a high degree of gingival inflammation. The levels of CSF-3 and tumor necrosis factor ligand superfamily member-10 TNFSF-10 were higher in cases with many deep periodontal pockets. The PerioGene North study includes detailed clinical periodontal data and uncovers a distinct serum protein profile in periodontitis. The findings of lower EGF and OLR-1 among the cases are highlighted, as this has not been presented before. The role of EGF and OLR-1 in periodontitis pathogenesis and as possible future biomarkers should be further explored.

Oral microbiome, periodontal disease and systemic bone-related diseases in the era of homeostatic medicine

BACKGROUND

Homeostasis is a state of self-regulation and dynamic equilibrium, maintaining the good physiological functions of each system in living organisms. In the oral cavity, the interaction between the host and the oral microbiome forms oral microbial homeostasis. Physiological bone remodeling and renewal can occur under the maintenance of oral microbial homeostasis. The imbalance of bone homeostasis is a key mechanism leading to the occurrence of systemic bone-related diseases. Considering the importance of oral microbial homeostasis in the maintenance of bone homeostasis, it still lacks a complete understanding of the relationship between oral microbiome, periodontal disease and systemic bone-related diseases.

AIM OF REVIEW

This review focuses on the homeostatic changes, pathogenic routes and potential mechanisms in the oral microbiome in periodontal disease and systemic bone-related diseases such as rheumatoid arthritis, osteoarthritis, osteoporosis and osteomyelitis. Additionally, this review discusses oral microbiome-based diagnostic approaches and explores probiotics, mesenchymal stem cells, and oral microbiome transplantation as promising treatment strategies.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review highlights the association between oral microbial homeostasis imbalance and systemic bone-related diseases, and highlights the possibility of remodeling oral microbial homeostasis for the prevention and treatment of systemic bone-related diseases.

Assessment of the Potential Role of Preoperative Dental Clearance in Total Joint Arthroplasty Optimization: A Pilot Study

AIMS AND OBJECTIVES

Periprosthetic joint infection (PJI) is a serious complication after total joint arthroplasty (TJA) and is associated with significant morbidity, mortality, and cost. This pilot study primarily aimed to investigate if preoperative dental screenings would impact the rate of PJI following TJA when compared to historical controls. Secondarily, this study aimed to evaluate the prevalence of dental pathology in patients undergoing TJA.

METHODS

Charts from 103 consecutive patients undergoing primary or revision total hip arthroplasty (THA, rTHA) or total knee arthroplasty (TKA, rTKA) by a single surgeon at a single academic institution over a two-year period were reviewed and selected for inclusion. All patients were referred to a dentist for preoperative clearance using a standardized form. The rate of dental pathology before surgery, details of the dental intervention required, and any dental work performed within six months postoperatively were evaluated. The demographic and comorbidity composition of our patient population was also collected. Finally, rates of PJI following each type of TJA were obtained for demographic- and comorbidity-matched historical controls from similar study designs to examine the potential impact of preoperative dental intervention.

RESULTS

Of the 103 patients, 31 (30.1%) were found to have preoperative dental pathology. Twenty-eight of these 31 patients (90.3%) required dental intervention prior to surgery. Based on demographic- and comorbidity-matched historical data, we expected two (95% CI (0, 6)) PJI cases for the THA group, 0 (95% CI (0, 2)) PJI cases for the TKA group, two (95% CI (0, 5)) PJI cases for the rTHA group, and two (95% CI (0, 5)) PJI cases for the rTKA group. However, in our study, there were no PJIs after any TJA up to the latest follow-up, which was unlikely for THA, rTHA, and rTKA groups given the calculated Poisson probabilities (9.39%, 15.11%, and 11.26%, respectively). Finding 0 cases was likely for the TKA group given the calculated Poisson probability of 72.61%.

CONCLUSIONS

This pilot study demonstrated that preoperative dental screening, which aims to decrease the chance of PJI due to bacteremia, may have an impact on the rate of PJI following THA, rTKA, and rTHA but not TKA based on Poisson probabilities calculated from demographic- and comorbidity-matched historical controls that lacked preoperative dental screening. For THA, rTKA, and rTHA, the Poisson probabilities of observing 0 cases of PJI postoperatively, as was the case in our study, were unlikely, suggesting that some variable in our cohort was decreasing the PJI rate for these groups. However, in the case of TKA, the Poisson probability of observing 0 cases was likely and matched the results of our study, suggesting that no variable in our cohort was affecting the PJI rate for this group. We cannot draw direct conclusions from this retrospective observational study, but the preliminary findings prompt further investigation through an appropriately controlled, blinded, multi-centered, and powered prospective randomized controlled trial.

The Presence of Bacteremia in 13 Dogs Undergoing Oral Surgery Without the Use of Antibiotic Therapy

This study aimed to assess if transient bacteremia developed from dental scaling, root planing (SRP) and dental extraction(s), if the bacteria originated from oral flora, and if the amount of bacteremia produced would warrant the use of pre-, intra-, or post-operative antibiotic therapy in healthy canine patients. Blood cultures were obtained from 13 healthy dogs with chronic periodontal disease that necessitated the extraction of one tooth or multiple teeth. Patients included did not receive any antibiotic therapy for a minimum of 2 weeks prior to their scheduled procedure and did not receive antibiotic therapy intra- or post-operatively. Blood collection occurred at specific time increments to determine the presence of bacteremia and if clearance of the bacteremia occurred post-procedure. The study found transient bacteremia developed at different time increments throughout the dental procedure. At the time of the final sample collection, no bacterial growth was evident in any of the blood cultures. Results of the blood cultures indicated that only four of 13 dogs had evidence of bacterial growth at any one of the time increments; however, by the final collection, there was no bacterial growth suggesting the transient bacteremia had cleared without the use of systemic antimicrobial therapy. The study findings indicate that systemic antibiotic usage is not warranted for severe periodontal disease where an episode of transient bacteremia is produced from SRP and dental extractions in an otherwise healthy patient.

Association between masticatory function, frailty, and functional disability: an observational study

BACKGROUND

Increase in functional disability in aging societies is an international medical and public health issue. Masticatory function may be a potential risk factor for functional disability, but the role of frailty in the association has not been clarified.

METHODS

Forty thousand five hundred sixty-two community-dwelling older adults aged 65 years and over who were insured by public health insurance as of April 2018 were followed up for a median of 3.0 years. Masticatory function was categorized as good, moderate, or poor based on a self-reported questionnaire. The development of functional disability was defined as a new certification of the need for long-term care. A Cox proportional hazards model was used to calculate hazard ratios (HRs) and their 95% confidence intervals (CIs).

RESULTS

During the follow-up period, 1,397 individuals experienced functional disability. After adjusting for age, sex, comorbidities, medical history, and lifestyle behaviors, the HR for incident functional disability was significantly higher in the moderate and poor groups compared to the good group (moderate, HR 1.21 [95% CI, 1.07-1.37]; poor, HR 1.64 [95% CI, 1.03-2.62]). However, after additional adjustment for frailty-related factors-namely, underweight, regular exercise, and gait speed-the association was attenuated in both the moderate group (HR 1.06 [95% CI, 0.94-1.21]) and the poor group (HR 1.51 [95% CI, 0.94-2.41]).

CONCLUSIONS

Masticatory dysfunction was significantly associated with incident functional disability in a community-dwelling older Japanese population. Our findings suggest that masticatory dysfunction may be a surrogate of frailty rather than a direct cause of functional disability.

An outer membrane vesicle specific lipoprotein promotes Porphyromonas gingivalis aggregation on red blood cells

Porphyromonas gingivalis uses a variety of mechanisms to actively interact with and promote the hydrolysis of red blood cells (RBCs) to obtain iron in the form of heme. In this study, we investigated the function of lipoprotein PG1881 which was previously shown to be up-regulated during subsurface growth and selectively enriched on outer membrane vesicles (OMVs). Our results show that wildtype strain W83 formed large aggregates encompassing RBCs whereas the PG1881 deletion mutant remained predominately as individual cells. Using a PG1881 antibody, immunofluorescence revealed that the wildtype strain's aggregation to RBCs involves an extracellular matrix enriched with PG1881. Our findings discover that RBCs elicit cell aggregation and matrix formation by P. gingivalis and that this process is promoted by an OMV-specific lipoprotein. We propose this strategy is advantageous for nutrient acquisition as well as dissemination from the oral cavity and survival of this periodontal pathogen.

Multifunctional role of oral bacteria in the progression of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of liver disorders of varying severity, ultimately leading to fibrosis. This spectrum primarily consists of NAFL and non-alcoholic steatohepatitis. The pathogenesis of NAFLD is closely associated with disturbances in the gut microbiota and impairment of the intestinal barrier. Non-gut commensal flora, particularly bacteria, play a pivotal role in the progression of NAFLD. Notably, Porphyromonas gingivalis, a principal bacterium involved in periodontitis, is known to facilitate lipid accumulation, augment immune responses, and induce insulin resistance, thereby exacerbating fibrosis in cases of periodontitis-associated NAFLD. The influence of oral microbiota on NAFLD via the "oral-gut-liver" axis is gaining recognition, offering a novel perspective for NAFLD management through microbial imbalance correction. This review endeavors to encapsulate the intricate roles of oral bacteria in NAFLD and explore underlying mechanisms, emphasizing microbial control strategies as a viable therapeutic avenue for NAFLD.

P. gingivalis in oral-prostate axis exacerbates benign prostatic hyperplasia via IL-6/IL-6R pathway

BACKGROUND

Benign prostatic hyperplasia (BPH) is the most common disease in elderly men. There is increasing evidence that periodontitis increases the risk of BPH, but the specific mechanism remains unclear. This study aimed to explore the role and mechanism of the key periodontal pathogen Porphyromonas gingivalis (P. gingivalis) in the development of BPH.

METHODS

The subgingival plaque (Sp) and prostatic fluid (Pf) of patients with BPH concurrent periodontitis were extracted and cultured for 16S rDNA sequencing. Ligature-induced periodontitis, testosterone-induced BPH and the composite models in rats were established. The P. gingivalis and its toxic factor P. gingivalis lipopolysaccharide (P.g-LPS) were injected into the ventral lobe of prostate in rats to simulate its colonization of prostate. P.g-LPS was used to construct the prostate cell infection model for mechanism exploration.

RESULTS

P. gingivalis, Streptococcus oralis, Capnocytophaga ochracea and other oral pathogens were simultaneously detected in the Pf and Sp of patients with BPH concurrent periodontitis, and the average relative abundance of P. gingivalis was found to be the highest. P. gingivalis was detected in both Pf and Sp in 62.5% of patients. Simultaneous periodontitis and BPH synergistically aggravated prostate histological changes. P. gingivalis and P.g-LPS infection could induce obvious hyperplasia of the prostate epithelium and stroma (epithelial thickness was 2.97- and 3.08-fold that of control group, respectively), and increase of collagen fibrosis (3.81- and 5.02-fold that of control group, respectively). P. gingivalis infection promoted prostate cell proliferation, inhibited apoptosis, and upregulated the expression of inflammatory cytokines interleukin-6 (IL-6; 4.47-fold), interleukin-6 receptor-α (IL-6Rα; 5.74-fold) and glycoprotein 130 (gp130; 4.47-fold) in prostatic tissue. P.g-LPS could significantly inhibit cell apoptosis, promote mitosis and proliferation of cells. P.g-LPS activates the Akt pathway through IL-6/IL-6Rα/gp130 complex, which destroys the imbalance between proliferation and apoptosis of prostate cells, induces BPH.

CONCLUSION

P. gingivalis was abundant in the Pf of patients with BPH concurrent periodontitis. P. gingivalis infection can promote BPH, which may affect the progression of BPH via inflammation and the Akt signaling pathway.

Porphyromonas gingivalis, a bridge between oral health and immune evasion in gastric cancer

Porphyromonas gingivalis (P. gingivalis) is a gram-negative oral pathogen associated with chronic periodontitis. Previous studies have linked poor oral health and periodontitis with oral cancer. Severe cases of periodontal disease can result in advanced periodontitis, leading to tissue degradation, tooth loss, and may also correlate with higher gastric cancer (GC) risk. In fact, tooth loss is associated with an elevated risk of cancer. However, the clinical evidence for this association remains inconclusive. Periodontitis is also characterized by chronic inflammation and upregulation of members of the Programmed Death 1/PD1 Ligand 1 (PD1/PDL1) axis that leads to an immunosuppressive state. Given that chronic inflammation and immunosuppression are conditions that facilitate cancer progression and carcinogenesis, we hypothesize that oral P. gingivalis and/or its virulence factors serve as a mechanistic link between oral health and gastric carcinogenesis/GC progression. We also discuss the potential impact of P. gingivalis' virulence factors (gingipains, lipopolysaccharide (LPS), and fimbriae) on inflammation and the response to immune checkpoint inhibitors in GC which are part of the current standard of care for advanced stage patients.

Microbiome interactions with different risk factors in development of myocardial infarction

Among all non-communicable diseases, Cardiovascular Diseases (CVDs) stand as the leading global cause of mortality. Within this spectrum, Myocardial Infarction (MI) strikingly accounts for over 15 % of all deaths. The intricate web of risk factors for MI, comprising family history, tobacco use, oral health, hypertension, nutritional pattern, and microbial infections, is firmly influenced by the human gut and oral microbiota, their diversity, richness, and dysbiosis, along with their respective metabolites. Host genetic factors, especially allelic variations in signaling and inflammatory markers, greatly affect the progression or severity of the disease. Despite the established significance of the human microbiome-nutrient-metabolite interplay in associations with CVDs, the unexplored terrain of the gut-heart-oral axis has risen as a critical knowledge gap. Moreover, the pivotal role of the microbiome and the complex interplay with host genetics, compounded by age-related changes, emerges as an area of vital importance in the development of MI. In addition, a distinctive disease susceptibility and severity influenced by gender-based or ancestral differences, adds a crucial insights to the association with increased mortality. Here, we aimed to provide an overview on interactions of microbiome (oral and gut) with major risk factors (tobacco use, alcohol consumption, diet, hypertension host genetics, gender, and aging) in the development of MI and therapeutic regulation.

Periodontitis, Dental Procedures, and Young-Onset Cryptogenic Stroke

Periodontitis is associated with an increased risk of ischemic stroke, and the risk may be particularly high among young people with unexplained stroke etiology. Thus, we investigated in a case-control study whether periodontitis or recent invasive dental treatments are associated with young-onset cryptogenic ischemic stroke (CIS). We enrolled participants from a multicenter case-control SECRETO study including adults aged 18 to 49 y presenting with an imaging-positive first-ever CIS and stroke-free age- and sex-matched controls. Thorough clinical and radiographic oral examination was performed. Furthermore, we measured serum lipopolysaccharide (LPS) and lipotechoic acid (LTA) levels. Multivariate conditional regression models were adjusted for stroke risk factors, regular dentist visits, and patent foramen ovale (PFO) status. We enrolled 146 case-control pairs (median age 41.9 y; 58.2% males). Periodontitis was diagnosed in 27.5% of CIS patients and 20.1% of controls (P < 0.001). In the fully adjusted models, CIS was associated with high periodontal inflammation burden (odds ratio [OR], 95% confidence interval) with an OR of 10.48 (3.18-34.5) and severe periodontitis with an OR of 7.48 (1.24-44.9). Stroke severity increased with the severity of periodontitis, having an OR of 6.43 (1.87-23.0) in stage III to IV, grade C. Invasive dental treatments performed within 3 mo prestroke were associated with CIS, with an OR of 2.54 (1.01-6.39). Association between CIS and invasive dental treatments was especially strong among those with PFO showing an OR of 6.26 (1.72-40.2). LPS/LTA did not differ between CIS patients and controls but displayed an increasing trend with periodontitis severity. Periodontitis and recent invasive dental procedures were associated with CIS after controlling for multiple confounders. However, the role of bacteremia as a mediator of this risk was not confirmed.

The association between periodontitis and cerebrovascular disease, and dementia. Scientific report of the working group of the Spanish Society of Periodontology and the Spanish Society of Neurology

OBJECTIVE

This article reviews the scientific evidence on the relationship between periodontitis and neurological disease, and particularly cerebrovascular disease and dementia. We also issue a series of recommendations regarding the prevention and management of periodontitis and these neurological diseases at dental clinics and neurology units.

DEVELOPMENT

In response to a series of questions proposed by the SEPA-SEN working group, a literature search was performed, with no restrictions on study design, to identify the most relevant articles on the association between periodontitis and cerebrovascular disease and dementia from the perspectives of epidemiology, treatment, and the biological mechanisms involved in these associations.

CONCLUSIONS

Periodontitis increases the risk of ischaemic stroke and Alzheimer dementia. Recurrent bacterial infections and increased low-grade systemic inflammation seem to be possible biological mechanisms underlying this association. Limited evidence suggests that various oral health interventions can reduce the future risk of cerebrovascular disease and dementia.

Brain Abscess Caused by Oral Cavity Bacteria: A Nationwide, Population-based Cohort Study

BACKGROUND

Oral cavity bacteria are the most frequent etiology of brain abscess. Yet, data on the clinical presentation and outcome are scarce.

METHODS

We performed a nationwide, population-based study comprising all adults (aged ≥18 years) with brain abscess due to oral cavity bacteria in Denmark from 2007 through 2020. Prognostic factors for unfavorable outcome (Glasgow outcome scale, 1-4) were examined using modified Poisson regression to compute adjusted relative risks (RRs) with 95% confidence intervals (CIs).

RESULTS

Among 287 identified patients, the median age was 58 years (interquartile range, 47-66), and 96 of 287 (33%) were female. Preexisting functional impairment was absent or mild in 253 of 280 (90%), and risk factors for brain abscess included immunocompromise in 95 of 287 (33%), dental infection in 68 of 287 (24%), and ear-nose-throat infection in 33 of 287 (12%). Overall, a neurological deficit was present in 246 of 276 (86%) and in combination with headache and fever in 64 of 287 (22%). Identified microorganisms were primarily the Streptococcus anginosus group, Fusobacterium, Actinomyces, and Aggregatibacter spp., and 117 of 287 (41%) were polymicrobial. Unfavorable outcome occurred in 92 of 246 (37%) at 6 months after discharge and was associated with antibiotics before neurosurgery (RR, 3.28; 95% CI, 1.53-7.04), rupture (RR, 1.89; 95% CI, 1.34-2.65), and immunocompromise (RR, 1.80; 95% CI, 1.29-2.51), but not with specific targeted antibiotic regimens. Identified dental infection was associated with favorable prognosis (RR, 0.58; 95% CI, .36-.93).

CONCLUSIONS

Brain abscess due to oral cavity bacteria often occurred in previously healthy individuals without predisposing dental infections. Important risk factors for unfavorable outcome were rupture and immunocompromise. However, outcome was not associated with specific antibiotic regimens supporting carbapenem-sparing strategies.

Long-term follow-up of a healthy man with endogenous Streptococcus anginosus endophthalmitis

We report the long-term follow-up of an immunocompetent patient who presented with slowly progressive endogenous endophthalmitis secondary to Streptococcus anginosus. A 46-year-old healthy man presented with a two-month history of right eye iritis. On examination, visual acuity was 20/60 with intraocular pressure of 6 mm Hg. There was a small layer of hypopyon with non-granulomatous anterior uveitis and vitritis. On funduscopy, fluffy white peripheral retinal and pre-retinal lesions were noted in superonasal periphery. The patient denied any present or past illness. Diagnostic pars plana vitrectomy was performed. Culture and polymerase chain reaction of the vitreous sample were positive for Streptococcus anginosus. Intravitreal vancomycin and ceftazidime and systemic ceftriaxone were administered. Work-up which included blood and urine cultures, chest x-ray, echocardiography and abdominal ultrasound was unyielding. Subsequently and because of persistent post-infectious inflammatory reaction, intravitreal and oral steroids were administered in addition to oral azathioprine later on. After one year of follow-up, visual acuity was 20/20 with near vision of Jaeger 3 + and no signs of active uveitis were seen. Therefore, Streptococcus anginosus should be considered in the differential diagnosis of a slowly progressive endophthalmitis also in immunocompetent individuals.

Exploring the presence of oral bacteria in non-oral sites of patients with cardiovascular diseases using whole metagenomic data

Cardiovascular diseases (CVDs) encompass various conditions affecting the heart and its blood vessels and are often linked with oral microbes. Our data analysis aimed to identify oral bacteria from other non-oral sites (i.e., gut, arterial plaque and cultured blood) that could be linked with CVDs. Taxonomic profiling identified bacteria to the species level and compared with the Human Oral Microbiome Database (HOMD). The oral bacteria in the gut, cultured blood and arterial plaque samples were catalogued, with their average frequency calculated for each sample. Additionally, data were filtered by comparison with the Human Microbiome Project (HMP) database. We identified 17,243 microbial species, of which 410 were present in the HOMD database and further denominated as "oral", and were found in at least one gut sample, but only 221 and 169 species were identified in the cultured blood and plaque samples, respectively. Of the 410 species, 153 were present solely in oral-associated environments after comparison with the HMP database, irrespective of their presence in other body sites. Our results suggest a potential connection between the presence of specific species of oral bacterial and occurrence of CVDs. Detecting these oral bacterial species in non-oral sites of patients with CVDs could help uncover the link between oral health and general health, including cardiovascular conditions via bacterial translocation.

Nisin lantibiotic prevents NAFLD liver steatosis and mitochondrial oxidative stress following periodontal disease by abrogating oral, gut and liver dysbiosis

Oral microbiome dysbiosis mediates chronic periodontal disease, gut microbial dysbiosis, and mucosal barrier disfunction that leads to steatohepatitis via the enterohepatic circulation. Improving this dysbiosis towards health may improve liver disease. Treatment with antibiotics and probiotics have been used to modulate the microbial, immunological, and clinical landscape of periodontal disease with some success. The aim of the present investigation was to evaluate the potential for nisin, an antimicrobial peptide produced by Lactococcus lactis, to counteract the periodontitis-associated gut dysbiosis and to modulate the glycolipid-metabolism and inflammation in the liver. Periodontal pathogens, namely Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia and Fusobacterium nucleatum, were administrated topically onto the oral cavity to establish polymicrobial periodontal disease in mice. In the context of disease, nisin treatment significantly shifted the microbiome towards a new composition, commensurate with health while preventing the harmful inflammation in the small intestine concomitant with decreased villi structural integrity, and heightened hepatic exposure to bacteria and lipid and malondialdehyde accumulation in the liver. Validation with RNA Seq analyses, confirmed the significant infection-related alteration of several genes involved in mitochondrial dysregulation, oxidative phosphorylation, and metal/iron binding and their restitution following nisin treatment. In support of these in vivo findings indicating that periodontopathogens induce gastrointestinal and liver distant organ lesions, human autopsy specimens demonstrated a correlation between tooth loss and severity of liver disease. Nisin's ability to shift the gut and liver microbiome towards a new state commensurate with health while mitigating enteritis, represents a novel approach to treating NAFLD-steatohepatitis-associated periodontal disease.

Brain abscess of odontogenic origin: A case report and literature review

BACKGROUND

The objective of this study is to investigate and understand the characteristics of odontogenic brain abscess.

METHODS

A case of brain abscess suspected to be caused by odontogenic infection was documented, and a comprehensive analysis and summary of odontogenic brain abscess cases reported in various countries over the past 20 years was conducted.

RESULTS

Based on the analysis and synthesis of both the present and previous reports, we have examined and consolidated the distinctive features of odontogenic brain abscess, the potential transmission pathway of pathogenic bacteria, diagnostic assertions, verification techniques, and crucial considerations during treatment.

CONCLUSION

This investigation contributes to an enhanced comprehension and improved clinical identification of odontogenic brain abscess.

Saliva: a challenging human fluid to diagnose brain disorders with a focus on Alzheimer's disease

Biomarkers are molecules of biological processes that help in both the diagnosis of human diseases and in follow-up assessments of therapeutic responses. Biomarkers can be measured in many human fluids, such as blood, cerebrospinal fluid, urine, and saliva. The -omics methods (genomics, RNomics, proteomics, and metabolomics) are useful at measuring thousands of markers in a small volume. Saliva is a human fluid that is easily accessible, without any ethical concerns. Yet, saliva remains unexplored in regard to many human disease biomarkers. In this review, we will give an overview on saliva and how it can be influenced by exogenous factors. As we focus on the potential use of saliva as a diagnostic tool in brain disorders (especially Alzheimer's disease), we will cover how saliva is linked to the brain. We will discuss that saliva is a heterogeneous human fluid, yet useful for the discovery of biomarkers in human disorders. However, a procedure and consensus that is controlled, validated, and standardized for the collection and processing of saliva is required, followed by a highly sensitive diagnostic approach.

Pelvic infection caused by periodontitis: A case report

Oral bacteria in patients with periodontitis can disseminate into the bloodstream via broken oral epithelial cells, causing odontogenic maxillofacial infections, brain abscesses and endocarditis. However, pelvic infection caused by periodontitis is rare. The case of a 48-year-old woman with a long history of recurrent periodontal infections, who complained of abdominal distention and pain for 14 days after dental implantation, is reported here. Pelvic ultrasound and magnetic resonance imaging signaled multiple inflammatory encapsulated effusions in the posterior uterus, which were removed by laparoscopic surgery and tested with metagenomic next-generation sequencing (mNGS). Through mNGS, numerous oral pathogens, including Filifactor alocis, were identified in the pelvic effusions. The patient was subsequently diagnosed with a pelvic infection originating from periodontitis, and recovered after undergoing surgery and targeted antibacterial treatment. Thus, the possibility of extrabuccal complications in patients with a history of periodontitis or invasive oral procedures merits closer attention.

Exploring the link between poor oral hygiene and mesh infection after hernia repair: a systematic review and proposed best practices

BACKGROUND

There is a reasonable body of evidence around oral/dental health and implant infection in orthopaedic and cardiovascular surgery. Another large area of surgical practice associated with a permanent implant is mesh hernia repair. This study aimed to review the evidence around oral/dental health and mesh infection.

METHODS

The research protocol was registered in PROSPERO (CRD42022334530). A systematic review of the literature was undertaken according to the PRISMA 2020 statement. The initial search identified 582 publications. A further four papers were identified from references. After a review by title and abstract, 40 papers were read in full text. Fourteen publications were included in the final review, and a total of 47,486 patients were included.

RESULTS

There is no published evidence investigating the state of oral hygiene/health and the risk of mesh infection or other infections in hernia surgery. Improvement in oral hygiene/health can reduce surgical site infection and implant infection in colorectal, gastric, liver, orthopaedic and cardiovascular surgery. Poor oral hygiene/health is associated with a large increase in oral bacteria and bacteraemia in everyday activities such as when chewing or brushing teeth. Antibiotic prophylaxis does not appear to be necessary before invasive dental care in patients with an implant.

CONCLUSION

Good oral hygiene and oral health is a strong public health message. The effect of poor oral hygiene on mesh infection and other complications of mesh hernia repair is unknown. While research is clearly needed in this area, extrapolating from evidence in other areas of surgery where implants are used, good oral hygiene/health should be encouraged amongst hernia patients both prior to and after their surgery.

Periodontitis and systemic inflammation as independent and interacting risk factors for mortality: evidence from a prospective cohort study

BACKGROUND

Recent studies have highlighted the role of low-grade systemic inflammation in linking periodontitis to cardiovascular disease (CVD) outcomes, but many aspects remain unclear. This study examines the independent and reciprocal associations of periodontitis and low-grade systemic inflammation with all-cause and CVD mortality in a large-scale cohort.

METHODS

A total of 3047 participants from the prospective, population-based Study of Health in Pomerania (SHIP-START) were followed for a period of 13.0 ± 2.4 years. For the association between various inflammation/periodontitis measures and mortality, hazard ratios (HRs) were obtained from covariate-adjusted Cox proportional hazards models. Interactions were analysed in joint models: on the multiplicative scale, HRs were reported and on the additive scale, relative excess risks due to interaction (RERI) were calculated. Subject and variable-specific interval records were used to account for time-varying exposures and covariates.

RESULTS

During the observation period, 380 (12.5%) individuals died from CVD (n = 125) or other causes (n = 255). All markers of periodontitis and inflammation showed apparent associations with all-cause mortality (HRs per SD-increase: mean PPD: 1.068 (95% confidence interval (CI): 0.988-1.155), mean CAL: 1.205 (95% CI: 1.097-1.323), missing teeth: 1.180 (95% CI: 1.065-1.307), periodontitis score: 1.394 (95% CI: 1.202-1.616), leukocytes: 1.264 (95% CI: 1.163-1.374), fibrinogen: 1.120 (95% CI: 1.030-1.218), CRP: 1.231 (95% CI: 1.109-1.366), inflammation score: 1.358 (95% CI: 1.210-1.523)). For CVD mortality, all PPD related variables showed significant associations. Interaction modelling revealed some variation with respect to mortality type and exposure combinations. On the additive scale, RERIs for periodontitis score and inflammation score implied 18.9% and 27.8% excess mortality risk for all-cause and CVD mortality, respectively. On the multiplicative scale, the HRs for interaction were marginal.

CONCLUSIONS

Both periodontitis and inflammation were significantly associated with all-cause mortality and CVD mortality. On the additive scale, a substantial excess risk was observed due to the interaction of periodontitis and inflammation, suggesting that the greatest treatment benefit may be achieved in patients with both periodontitis and high systemic inflammation. As periodontal therapy has been reported to also reduce systemic inflammation, the possibility of a reduction in CVD mortality risk by anti-inflammatory treatments, including periodontal interventions, seems worthy of further investigation.

Effects of probiotics in rats with experimental metabolic syndrome and periodontitis: An investigation of the intestine-adipose tissue axis

BACKGROUND

This study evaluated the systemic (intestine and adipose tissue) and local (periodontal tissues) impact of probiotic therapy in rats with metabolic syndrome (MS) associated or not with periodontitis (PE).

METHODS

Forty-eight rats received a high-fat diet for induction of MS for 16 weeks. They were subdivided into groups with (+) and without (-) PE, receiving (*) or not (**) receiving probiotics (PROB): MS (-**), MSP (-*), MSPE (+**), and MSPEP (+*). PROB administration (Bifidobacterium animalis subsp. lactis HN019) started on the 8th week of the study and PE was induced on the 14th week by placing ligature on the animals' lower first molars. Euthanasia occurred in the 16th week. Biomolecular, immunoenzymatic assays, and histomorphometric analyses were performed. The data obtained were statistically analyzed (ANOVA, Tukey, p < 0.05).

RESULTS

The MSPEP group exhibited reduced alveolar bone loss when compared with the MSPE group, as well as lower levels of hepatic steatosis and proteinuria (p < 0.05). In the intestinal environment, the MSPE group exhibited significantly lower villus height and crypt depth, as well as a greater increase in Bacillota when compared with the MSPEP group (p < 0.05). The MSPEP group showed lower adipokine gene expression (LEPR, NAMPT, and FABP4) in adipose tissue than the MSPE group (p < 0.05).

CONCLUSION

The probiotic B. lactis HN019 reduced the severity of experimental periodontitis and modulated the expression of lipogenic genes and intestinal morphological and microbiological parameters in rats with MS.

An Ex-Vivo Model for Investigating Bacterial Extrusion from Infected Root Canals during Masticatory Function

INTRODUCTION

The extrusion of bacteria from infected root canals may lead to increase in symptoms, expansion of periapical lesions, and contribution to systemic diseases. The aim of this study is to investigate a potential proof-of-concept model to study the extent to which bacteria can escape from infected root canals under dynamic loading (simulated chewing).

METHODS

The study was completed in 2 experiments performed at 2 institutions. Biofilms of Streptococcus intermedius in the first experiment and S. intermedius and Actinomyces naeslundii were allowed to grow in root canals of single-rooted extracted teeth for 3 weeks. The roots of the teeth were suspended in a small chamber containing dental transport medium and were mounted on a lower sample holder of a chewing simulator. In the experimental group, simulated chewing cycles equivalent to 1 year of function were conducted, and then bacterial migration was quantified and compared with stationary teeth.

RESULTS

All experimental samples of the loading group revealed bacterial penetration in both experiments. Several of the unloaded samples revealed no bacterial penetration. In the first experiment, a significantly higher number of bacteria were able to escape into the periapex of the loaded group compared with the unloaded group (P = .017). In the second experiment, there was no significant difference between the 2 bacterial species used in the amount of extruded bacteria; however, there was a highly significant effect for occlusal loading (P = .0001).

CONCLUSIONS

The potential for occlusal forces to enhance bacterial extrusion from infected root canals should be further explored.

Infective endocarditis: prevention strategy and risk factors in an animal model

INTRODUCTION

Infective endocarditis is a serious infection of the endocardium, especially the heart valves, which is associated with a high mortality rate. It generally occurs in patients with altered and abnormal cardiac architecture combined with exposure to bacteria from trauma and other potentially high-risk activities with transient bacteremia.

Bacteremia Prevention during Periodontal Treatment-An In Vivo Feasibility Study

The link between periodontitis and systemic diseases has increasingly become a focus of research in recent years. In this context, it is reasonable-especially in vulnerable patient groups-to minimize bacteremia during periodontal treatment. The aim of the present in vivo feasibility study was to investigate the possibility of laser-based bacteremia prevention. Patients with stage III, grade B generalized periodontitis were therefore treated in a split-mouth design either with prior 445 nm laser irradiation before nonsurgical periodontal therapy or without. During the treatments, clinical (periodontal measures, pain sensation, and body temperature), microbiological (sulcus samples and blood cultures before, 25 min after the start, and 10 min after the end of treatment), and immunological parameters (CRP, IL-6, and TNF-α) were obtained. It was shown that periodontal treatment-related bacteremia was detectable in both patients with the study design used. The species isolated were Schaalia georgiae, Granulicatella adiacens, and Parvimonas micra. The immunological parameters increased only slightly and occasionally. In the laser-assisted treatments, all blood cultures remained negative, demonstrating treatment-related bacteremia prevention. Within the limitations of this feasibility study, it can be concluded that prior laser disinfection can reduce bacteremia risk during periodontal therapy. Follow-up studies with larger patient numbers are needed to further investigate this effect, using the study design presented here.

Neutrophils' Contribution to Periodontitis and Periodontitis-Associated Cardiovascular Diseases

Neutrophils represent the primary defense against microbial threats playing a pivotal role in maintaining tissue homeostasis. This review examines the multifaceted involvement of neutrophils in periodontitis, a chronic inflammatory condition affecting the supporting structures of teeth summarizing the contribution of neutrophil dysfunction in periodontitis and periodontal-related comorbidities. Periodontitis, a pathological condition promoted by dysbiosis of the oral microbiota, is characterized by the chronic inflammation of the gingiva and subsequent tissue destruction. Neutrophils are among the first immune cells recruited to the site of infection, releasing antimicrobial peptides, enzymes, and reactive oxygen species to eliminate pathogens. The persistent inflammatory state in periodontitis can lead to aberrant neutrophil activation and a sustained release of proinflammatory mediators, finally resulting in tissue damage, bone resorption, and disease progression. Growing evidence now points to the correlation between periodontitis and systemic comorbidities. Indeed, the release of inflammatory mediators, immune complexes, and oxidative stress by neutrophils, bridge the gap between local and systemic immunity, thus highlighting neutrophils as key players in linking periodontal inflammation to chronic conditions, including cardiovascular diseases, diabetes mellitus, and rheumatoid arthritis. This review underscores the crucial role of neutrophils in the pathogenesis of periodontitis and the complex link between neutrophil dysfunction, local inflammation, and systemic comorbidities. A comprehensive understanding of neutrophil contribution to periodontitis development and their impact on periodontal comorbidities holds significant implications for the management of oral health. Furthermore, it highlights the need for the development of novel approaches aimed at limiting the persistent recruitment and activation of neutrophils, also reducing the impact of periodontal inflammation on broader health contexts, offering promising avenues for improved disease management and patient care.

The role of periodontitis-associated bacteria in Alzheimer's disease: A narrative review

Alzheimer's disease causes memory loss and dementia in older adults through a neurodegenerative mechanism. Despite the pathophysiological clarification of this cognitive disorder, novel molecular and cellular pathways should be identified to determine its exact mechanism. Alzheimer's disease (AD) is pathologically characterized by senile plaques comprising beta-amyloid and neurofibrillary tangles (NFTs) formed by hyperphosphorylated tau as a microtubule-associated protein with a key role in the pathogenesis of AD. Periodontitis through inflammatory pathways is a risk factor for deteriorating cognitive impairment in AD patients. Poor oral hygiene coupled with immunocompromised status in older adults causes periodontal diseases and chronic inflammations through an oral bacterial imbalance. Toxic bacterial products, including bacteria themselves, can reach the central nervous system through the bloodstream and evoke inflammatory responses. The present review was conducted to investigate relationships between AD and periodontitis-involved bacteria as a risk factor.

Associations of Dental Health With the Progression of Hippocampal Atrophy in Community-Dwelling Individuals: The Ohasama Study

BACKGROUND AND OBJECTIVES

Although tooth loss and periodontitis have been considered risk factors of Alzheimer disease, recent longitudinal researches have not found a significant association with hippocampal atrophy. Therefore, this study aimed to clarify a longitudinal association between the number of teeth present (NTP) and hippocampal atrophy dependent on the severity of periodontitis in a late middle-aged and older adult population.

METHODS

This study included community-dwelling individuals aged 55 years or older who had no cognitive decline and had undergone brain MRI and oral and systemic data collection twice at 4-year intervals. Hippocampal volumes were obtained from MRIs by automated region-of-interest analysis. The mean periodontal probing depth (PD) was used as a measure of periodontitis. Multiple regression analysis was performed with the annual symmetric percentage change (SPC) of the hippocampal volume as the dependent variable and including an interaction term between NTP and mean PD as the independent variable. The interaction details were examined using the Johnson-Neyman technique and simple slope analysis. The 3-way interaction of NTP, mean PD, and time on hippocampal volume was analyzed using a linear mixed-effects model, and the interaction of NTP and time was examined in subgroups divided by the median mean PD. In all models, dropout bias was adjusted by inverse probability weighting.

RESULTS

Data of 172 participants were analyzed. The qualitative interaction between NTP and the mean PD was significant for the annual SPC in the left hippocampus. The regression coefficient of the NTP on the annual SPC in the left hippocampus was positive (B = 0.038, p = 0.026) at the low-level mean PD (mean -1 SD) and negative (B = -0.054, p = 0.001) at the high-level mean PD (mean +1 SD). Similar results were obtained in the linear mixed-effects model; the interaction of NTP and time was significant in the higher mean PD group.

DISCUSSION

In a late middle-aged and older cohort, fewer teeth were associated with a faster rate of left hippocampal atrophy in patients with mild periodontitis, whereas having more teeth was associated with a faster rate of atrophy in those with severe periodontitis. The importance of keeping teeth healthy is suggested.

Impact of Dietary Nitrate on the Recovery of Therapy-related Vascular Health Impairments Following Standard Periodontal Aftercare Therapy: a Hypothesis-generating Subanalysis

This follow-up study assessed the impact of a nitrate-rich diet on salivary nitrate/nitrite levels and the recovery of therapy-induced vascular impairments in a cohort of 39 periodontitis patients treated by standard subgingival mechanical plaque removal (PMPR). At baseline, saliva samples for nitrate/nitrite analysis were collected, and peripheral/central blood and augmentation pressure was documented using the Arteriograph recording system. Immediately after, PMPR vascular parameters were reassessed. All study patients received a randomly allocated supply of a lettuce beverage to be consumed for 14 days, containing either a daily dosage of 200 mg nitrate (test group, n = 20) or being void of nitrate (placebo group, n = 19). At day 14, salivary and vascular parameters were reassessed. Initial salivary and vascular parameters did not differ significantly between the groups. PMPR impaired all vascular parameters in both groups with no differences between the groups. At day 14, salivary nitrate/nitrite levels of the test group were significantly elevated compared to baseline. All vascular parameters had significantly recovered from the impairment inflicted by PMPR. In the placebo group, by contrast, salivary parameters did not differ significantly from baseline, and the recovery of impaired vascular parameters was restricted to a significant improvement of diastolic blood pressure. Correlation analysis identified a significant inverse correlation between salivary nitrate/nitrite sum and central/peripheral blood pressure and augmentation pressure. In conclusion, the data of this subanalysis suggest that increasing salivary nitrate/nitrite levels by a diet rich in nitrate may improve recovery of therapy-induced vascular impairments after PMPR.

Cerebral abscesses with odontogenic origin: a population-based cohort study

Objectives

Recent studies have indicated that cerebral abscess (CA) patients with odontogenic origin are on the rise. However, CA patients are often poorly characterized and with an unknown etiologic background. The purpose of this study is to identify and characterize CA patients that may have an odontogenic origin based on microbiologic, radiographic, and/or clinical findings.

Materials and methods

This is a population-based cohort study analyzing retrospective and prospective data from CA patients. Radiographic examinations of panoramic radiographs (PRs) or computed tomography (CT) scans were conducted. CA patients characterized with odontogenic origin required the fulfilment of the following criteria on admission: (1) Oral pathologic conditions were the only bacterial infections present, (2) oral microorganisms were isolated in the purulent exudate from the brain, and (3) radiographically and/or clinical recordings of oral pathologic conditions.

Results

A total of 44 patients could be included in this study of which 25 (57%) were characterized as having CA with a likely odontogenic origin. Type two diabetes (T2D) (p = 0.014) and microorganisms of the Streptococcus anginosus group (SAG) (p < 0.01) were overrepresented in patients with CAs of odontogenic origin.

Conclusions

Odontogenic infections may cause CAs to a greater extent than previously assumed. T2D was overrepresented among patients with odontogenic CA. When microorganisms of the SAG were isolated from the brain pus, CA patients had a predisposing odontogenic or sinus infection.

Clinical relevance

The identification of patients with a likely odontogenic CA will contribute to understanding the etiology of the infectious disease and highlighting the importance of preserving oral health.

Who is in the driver's seat? Parvimonas micra: An understudied pathobiont at the crossroads of dysbiotic disease and cancer

Recent advances in our understanding of microbiome composition at sites of inflammatory dysbiosis have triggered a substantial interest in a variety of historically understudied bacteria, especially among fastidious obligate anaerobes. A plethora of new evidence suggests that these microbes play outsized roles in establishing synergistic polymicrobial infections at many different sites in the human body. Parvimonas micra is a prime example of such an organism. Despite being almost completely uncharacterized at the genetic level, it is one of the few species commonly detected in abundance at multiple mucosal sites experiencing either chronic or acute inflammatory diseases, and more recently, it has been proposed as a discriminating biomarker for multiple types of malignancies. In the absence of disease, P. micra is commonly found in low abundance, typically residing within the oral cavity and gastrointestinal tract. P. micra exhibits the typical features of an inflammophilic organism, meaning its growth actually benefits from active inflammation and inflammatory tissue destruction. In this mini-review, we will describe our current understanding of this underappreciated but ubiquitous pathobiont, specifically focusing upon the role of P. micra in polymicrobial inflammatory dysbiosis and cancer as well as the key emerging questions regarding its pathobiology. Through this timely work, we highlight Parvimonas micra as a significant driver of disease and discuss its unique position at the crossroads of dysbiosis and cancer.