Update on the Role of Cytokines as Oral Biomarkers in the Diagnosis of Periodontitis

Salivary Biomarkers of Inflammasome Activation in Unstable Periodontitis: A Case-Control Study

The objective of this study was to investigate the complex network of inflammasome-related biomarkers (NOD-like receptor thermal protein domain associated protein 3 [NLRP3], caspase-1, interleukin [IL]-1β, IL-18, and IL-37) in unstable periodontitis by examining the salivary concentrations of these specific biomarkers and correlating them with periodontal parameters.The design of this study was an observational case-control study. A salivary sample was collected from periodontally healthy patients (n = 40) and unstable periodontitis patients (n = 40). Full-mouth clinical periodontal parameters were recorded (plaque index, bleeding on probing, periodontal pocket depth, and clinical attachment loss). Enzyme-linked immunosorbent assay analyzed NLRP3, caspase-1, IL-1β, IL-18, and IL-37 salivary levels.The normality of the data was tested using the Shapiro-Wilk test. Mean, standard deviation, and percentages were used for data description. An independent sample t-test, Mann-Whitney U test, and chi-square test were used to compare the two groups with a p-value of < 0.05. Spearman's correlation analysis was conducted to examine the relationships between variables.In saliva samples, NLRP3, caspase-1, IL-1β, and IL-18 were the highest in the periodontitis group (p < 0.005), while IL-37 was highest in the healthy group (p < 0.005). There was significant (p < 0.012) negative weak correlation (-0.395) between IL-37 and IL-1β, and significant (p < 0.003) negative moderate correlation (-0.455) between IL-37 and IL-18 in the healthy group. A significant (0.031) positive weak correlation (0.342) was found between the salivary IL-37 and NLRP3, and a significant (p < 0.001) negative moderate correlation (-0.508) was found between salivary IL-37 and IL-1β, in the periodontitis group.The NLRP3 inflammasomes and their cytokines (caspase-1, IL-1β, and IL-18) significantly promote periodontal inflammation and tissue destruction. In contrast, IL-37 acts as an anti-inflammatory cytokine, inhibiting the activity of the NLRP3 inflammasome and reducing excessive inflammation. This interplay highlights the potential of targeting NLRP3 and enhancing IL-37 as a therapeutic approach for the treatment of periodontal disease.

Clinical effects of probiotics on the treatment of gingivitis and periodontitis: a systematic review and meta-analysis

AIMS

This study aimed to evaluate the impact of probiotics as an adjunct to periodontal therapy on clinical outcomes in patients with gingivitis and periodontitis through a meta-analysis of available evidence.

MATERIALS AND METHODS

A detailed bibliographic search on four databases (PubMed, Scopus, Cochrane and EMBASE) was conducted with a language restriction. The collected data were assessed according to the predefined eligibility criteria and randomized clinical trials reporting the effects of probiotics on plaque index (PI), bleeding on probing (BOP) and pocket probing depth (PPD) compared to control or placebo groups were selected and analysed. The risk of bias assessment was conducted using SYRCLE's RoB- 2 tool. The GRADEpro tool was used to determine the overall quality of evidence.

RESULTS

Twenty-four studies (10 about gingivitis and 14 about periodontitis) were included in the meta-analysis. In the gingivitis studies, lower but non-significant PI and BOP were found in the probiotic group. In periodontitis, lower PI (95%-CI [- 0.54; - 0.15], p = 0.001) were reported in the probiotic group, and this difference was greater in studies with longer follow-up. Lower BOP (95%-CI [- 0.58; - 0.05], p = 0.021) was also reported, but this difference was only significant in studies with a shorter follow-up (95%-CI [- 0.86; - 0.11], p = 0.012). Meta-analysis for PPD showed lower, but non-significant, values (95%-CI [- 0.53; + 0.03], p = 0.077). However, this difference became significant when assessing studies with shorter follow-up (95% CI [- 0.77; - 0.07], p = 0.019).

CONCLUSIONS

The meta-analysis provides evidence suggested that probiotics can serve as a beneficial adjunct to periodontal treatment in patients with periodontitis, particularly in improving clinical outcomes such as plaque index and bleeding on probing. The results from gingivitis studies highlight the need for further investigation to better understand the impact of probiotics in the early stages of periodontal disease. These findings emphasize the importance of future research with standardized protocols and longer follow-up periods to confirm and expand on the clinical utility of probiotics in periodontal therapy.

Association between periodontitis severity and prostate-specific antigen levels using the NHANES data

BACKGROUND

Periodontitis has been linked to various systemic health conditions. This study investigated whether the association between periodontitis and prostate-specific antigen (PSA) is direct or mediated through intermediary systemic diseases.

METHODS

Three data cycles (2001-2002, 2003-2004, and 2009-2010) from the National Health and Nutrition Examination Survey (NHANES) comprising 12,874 subjects were included, and 3020 male participants were analyzed for demographic information, periodontal health indicators, systemic conditions, PSA, and C-reactive protein (CRP) levels. The severity of periodontitis was assessed based on tooth loss, the 2012 Centers for Disease Control and Prevention (CDC)/American Academy of Periodontology (AAP) severity, the 2017 European Federation of Periodontology (EFP)/AAP Workshop stage, and a composite outcome of stage and open pocket percentage. Multilevel stepwise regression analysis examined the association between periodontitis severity (expressed by staging and open pocket percentage) and total PSA levels. Mediation analysis explored potential mediators affecting PSA levels, such as calcium (Ca) levels, osteoporosis, arthritis, and CRP. Logistic regression models were also used to assess the likelihood of elevated PSA levels based on different thresholds (>2 ng/mL, >2.5 ng/mL, >4 ng/mL). Additionally, the data from a complete follow-up survey of 58 patients from the 2003-2004 cycle were included in the analysis.

RESULTS

The study revealed a marginal association between the composite outcome and total PSA levels (p < 0.05). However, logistic regression failed to establish significant associations between periodontitis indicators and elevated PSA levels. Mediation analysis demonstrated that Ca levels, osteoporosis, arthritis, and CRP did not significantly mediate this relationship. The follow-up revealed that edentulous patients were more likely to require additional prostate therapy.

CONCLUSION

There is a marginal association between periodontitis severity and total PSA levels with no significant mediation through factors such as Ca levels, osteoporosis, arthritis, or CRP. Longitudinally, edentulous patients were more likely to require more invasive prostate therapy in the future.

PLAIN LANGUAGE SUMMARY

Periodontitis is an inflammatory condition known to be associated with systemic health. This study aimed to investigate a potential association between periodontitis and prostate cancer, focusing on levels of prostate-specific antigen (PSA), a marker used in prostate cancer screening. Age, race, periodontitis severity, and open pocket percentage were significantly associated with total PSA levels. However, this increase did not significantly correlate with the defined PSA cutoff points of 2, 2.5, and 4. Additionally, calcium levels, osteoporosis, arthritis, and C-reactive protein levels as potential mediators did not significantly impact this relationship. Moreover, edentulous patients were significantly associated with higher odds of needing further treatment for prostate disease. Hence, while considering cases where periodontal disease may contribute to systemic prostate issues, implementing a dual-therapy strategy that addresses both the local inflammation as well as the systemic effects of periodontal disease might be a more effective approach in the management of these conditions.

Smart biomaterial gels for periodontal therapy: A novel approach

Periodontitis, a chronic inflammatory condition of the oral cavity, is characterized by the progressive destruction of the supporting structures of the teeth. The pathogenic effects of periodontopathogens extend beyond the local periodontal environment, contributing to systemic health complications, thereby underscoring the need for effective therapeutic strategies. Current standard treatments, which involve mechanical debridement coupled with systemic anti-inflammatory and antibiotic therapies, are often associated with limited efficacy, adverse effects, and the emergence of antibiotic resistance. Recent advancements in localized drug delivery systems present an innovative alternative, offering site-specific targeting with sustained therapeutic action. Smart drug delivery platforms, designed to respond to the unique microenvironment of periodontal pockets, undergo physicochemical transformations such as gelation or controlled drug release, enhancing treatment efficacy. This review comprehensively explores the etiological and prognostic factors of periodontitis, critical diagnostic biomarkers, and an in-depth analysis of stimuli-responsive biomacromolecule-based gels. These systems are evaluated for their structural properties, biological compatibility, and therapeutic potential while addressing their limitations and barriers to clinical translation. By integrating insights into the interplay between material properties and biological performance, this review highlights the future role of these advanced delivery systems in overcoming challenges in periodontal healthcare. Such approaches aim to bridge the gap between bench-side innovation and bedside application, offering the transformative potential to enhance therapeutic outcomes and improve patient quality of life in managing periodontal diseases.

Cytokines in gingivitis and periodontitis: from pathogenesis to therapeutic targets

Chronic inflammatory processes in the oral mucosa and periodontitis are common disorders caused by microflora and microbial biofilms. These factors activate both the innate and adaptive immune systems, leading to the production of pro-inflammatory cytokines. Cytokines are known to play a crucial role in the pathogenesis of gingivitis and periodontitis and have been proposed as biomarkers for diagnosis and follow-up of these diseases. They can activate immune and stromal cells, leading to local inflammation and tissue damage. This damage can include destruction of the periodontal ligaments, gingiva, and alveolar bone. Studies have reported increased local levels of pro-inflammatory cytokines, such as interleukin-1beta (IL-1beta), tumor necrosis factor (TNF), IL-6, IL-17, and IL-23, in patients with periodontitis. In experimental models of periodontitis, TNF and the IL-23/IL-17 axis play a pivotal role in disease pathogenesis. Inactivation of these pro-inflammatory pathways through neutralizing antibodies, genetic engineering or IL-10 function has been demonstrated to reduce disease activity. This review discusses the role of cytokines in gingivitis and periodontitis, with particular emphasis on their role in mediating inflammation and tissue destruction. It also explores new therapeutic interventions that offer potential for research and clinical therapy in these chronic inflammatory diseases.

The association between dental caries and serum crp in the us adult population: evidence from NHANES 2015-2018

BACKGROUND

Dental caries remains one of the most prevalent diseases worldwide, affecting 29.4% of the global population. Despite numerous efforts to diagnose, predict, and prevent dental caries, the incidence continues to rise. Salivary biomarkers provide a non-invasive means for early detection of various oral conditions. C-reactive protein (CRP) is a key marker, elevated in both oral and general inflammatory conditions such as diabetes, periodontitis and oral squamous cell carcinoma. Considering the emerging connection between oral and systemic health, it is worth exploring the various factors associated with this widespread disease. This study investigates the association between CRP levels and dental caries in the United States population, utilizing data from the National Health and Nutrition Examination Survey (NHANES).

METHODS

The study analyzed data from the 2015-2018 NHANES cycles, focusing on a nationally representative sample of individuals aged 30 years and above. Weighted multivariable negative binomial and logistic regression analyses were employed to explore the relationship between dental caries and CRP levels, adjusting for age, gender, race, education level, diabetes status, and gum disease.

RESULTS

The results of the negative binomial regression analysis demonstrated a positive association between higher CRP levels and an increased mean number of dental caries (Adjusted Mean Ratio [AMR] = 1.7; 95% CI: 1.3 - 2; P: < 0.001). The logistic regression analysis showed that individuals with higher CRP levels have a 50% increase in the odds of developing dental caries (AOR: 1.5, CI: 1.2 - 1.9; P: < 0.01).

CONCLUSION

The results of this cross-sectional study of the U.S. population highlight the positive association between high CRP levels and increased dental caries. These findings contribute to the growing body of evidence supporting the integration of oral and systemic health care. Further research is necessary to deepen our understanding of the mechanistic relationship between CRP levels and dental caries.

A Low-Cost Protocol Using the Adjunctive Action of Povidone-Iodine Irrigations and Sodium Hypochlorite Rinsing Solution in Step 2 of Periodontal Therapy for Patients with Stage III-IV Periodontitis: A Single-Blind, Randomized Controlled Trial

In severe stages of periodontitis, conventional periodontal therapy and maintenance care are usually insufficient due to the viral and bacterial etiology; thus, a mechanical approach alone may not be sufficient to eliminate a substantial portion of subgingival pathogens, especially in deep periodontal sites. Background and Objectives: This single-blind, randomized clinical trial aimed to compare the clinical and microbiological efficacy of a low-cost protocol using povidone-iodine and sodium hypochlorite formulations as adjuncts to non-surgical therapy for patients with stage IV periodontitis when compared with chlorhexidine, the most commonly employed substance to date for antimicrobial regimens in periodontal therapy. Materials and Methods: Forty-five patients were randomly divided into two groups: control (subgingival instrumentation, chlorhexidine-assisted) and test (antiviral medication, subgingival instrumentation with povidone-iodine, sodium hypochlorite rinsing solution, and antibiotics). Clinical measurements and microbiological analyses were performed at baseline and after three months. Results: After three months, notable differences were found in the bacterial detection scores for Porphyromonas gingivalis (a significant reduction in detection frequency was observed in the test compared to the control (p = 0.021)), and there were significant reductions in detection in the test group for Tannerella forsythia and Treponema denticola, showing undetectable levels (p < 0.0001 for both). In the test group, the pocket probing depth median value was reduced significantly (p = 0.0005); similarly, bleeding on probing showed a marked decrease (p < 0.0001). However, changes in clinical attachment loss and full-mouth plaque score were not statistically significant. Conclusions: Using the proposed protocol, substantial improvements in clinical and microbiological parameters were obtained when compared with the current antimicrobial recommendations.

A diet rich in omega-3 fatty acid improves periodontitis and tissue destruction by MMP2- and MMP9-linked inflammation in a murine model

Periodontitis is an oral-cavity inflammatory disease and is the principal cause associated with tooth loss. Matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) are important proteases involved in periodontal tissue destruction. The omega-3 polyunsaturated fatty acids (ω-3 PUFA) have been demonstrated to possess immunoregulatory properties in periodontitis. The aim of the study was to investigate the effects of ω-3 PUFA on inflammation and on the expression of MMP-2 and -9 in a murine periodontitis model. Twenty-four male C57BL/6 mice were divided into control mice (Control), control mice treated with ω-3 PUFA (O3), mice with periodontitis (P), and mice with periodontitis treated with ω-3 PUFA (P + O3). ω-3 PUFA were administered orally once a day for 70 days. Periodontitis in mice was induced by Porphyromonas gingivalis-infected ligature placement around the second maxillary molar. The mice were sacrificed, and blood and maxillary samples were collected. Flow cytometry was used to quantify tumor necrosis factor-alpha (TNFα), interleukin (IL)-2, IL-4, IL-5, and interferon-gamma. Histologic analysis and immunohistochemistry for MMP-2 and -9 were performed. The data were statistically evaluated using analysis of variance (ANOVA) and the Tukey post hoc test. Histological analysis showed that ω-3 PUFA supplementation prevented inflammation and tissue destruction and revealed that bone destruction was more extensive in the P group than in the P + O3 group (p < 0.05). Also, it decreased the serum expressions of TNFα and IL-2 and the tissue expression of MMP-2 and -9 in the periodontitis-induced model (p < 0.05). ω-3 PUFA supplementation prevented alveolar bone loss and periodontal destruction, probably by decreasing the expression of MMP-2 and MMP-9 and its immunoregulatory properties.

Accuracy of periodontitis diagnosis obtained using multiple molecular biomarkers in oral fluids: A systematic review and meta-analysis

AIM

To determine the accuracy of biomarker combinations in gingival crevicular fluid (GCF) and saliva through meta-analysis to diagnose periodontitis in systemically healthy subjects.

METHODS

Studies on combining two or more biomarkers providing a binary classification table, sensitivity/specificity values or group sizes in subjects diagnosed with periodontitis were included. The search was performed in August 2022 through PUBMED, EMBASE, Cochrane, LILACS, SCOPUS and Web of Science. The methodological quality of the articles selected was evaluated using the QUADAS-2 checklist. Hierarchical summary receiver operating characteristic modelling was employed to perform the meta-analyses (CRD42020175021).

RESULTS

Twenty-one combinations in GCF and 47 in saliva were evaluated. Meta-analyses were possible for six salivary combinations (median sensitivity/specificity values): IL-6 with MMP-8 (86.2%/80.5%); IL-1β with IL-6 (83.0%/83.7%); IL-1β with MMP-8 (82.7%/80.8%); MIP-1α with MMP-8 (71.0%/75.6%); IL-1β, IL-6 and MMP-8 (81.8%/84.3%); and IL-1β, IL-6, MIP-1α and MMP-8 (76.6%/79.7%).

CONCLUSIONS

Two-biomarker combinations in oral fluids show high diagnostic accuracy for periodontitis, which is not substantially improved by incorporating more biomarkers. In saliva, the dual combinations of IL-1β, IL-6 and MMP-8 have an excellent ability to detect periodontitis and a good capacity to detect non-periodontitis. Because of the limited number of biomarker combinations evaluated, further research is required to corroborate these observations.

Are Adults Over 18 Years of Age with Anaemia More Likely to Develop Chronic Periodontitis Than Adults Without Anaemia? - A Systematic Review and Meta-Analysis

Aims and Objectives

Periodontitis is a chronic disease affecting the supporting tissues of the teeth and exhibits bidirectional relation with systemic diseases. This study aims to determine the association between chronic periodontitis and erythrocyte functional measures: total red blood cells (RBCs), hemoglobin (Hb) concentration, mean corpuscular volume (MCV), and mean corpuscular hemoglobin concentration (MCHC) by systematic review and meta-analysis.

Materials and Methods

A systematic search of the electronic databases PUBMED, OVID, Embase, Web on Science, and Google Scholar was undertaken from inception to July 2022. English language studies that evaluated the erythrocyte functional measures in periodontitis and health were selected. Other review reports, letters/opinion articles, studies without a definition of periodontitis, and the concomitant presence of systemic conditions (diabetes, kidney disease, cancer) were excluded. Two reviewers determined full-text eligibility in a blinded process. Meta-Essentials software was used to generate forest plots and to determine heterogeneity and publication bias.

Results

Twenty-six studies involving 1082 patients with chronic periodontitis and 980 healthy controls were analyzed. Pooled results showed lower Hb concentration (Hedges' g = -1.16; 95% confidence intervals [CI], -1.7 to -0.62), RBC counts (Hedges' g = -0.85; 95% CI, -1.31 to -0.38) and packed cell volume (-0.56; 95% CI, -1.02 to -0.11) in patients with chronic periodontitis.

Conclusion

This meta-analysis showed a decreasing trend in the hematological parameters, including hemoglobin concentration, number of erythrocytes, and hematocrit in patients with chronic periodontitis compared to healthy controls.

Periodontal Inflamed Surface Area (PISA) associates with composites of salivary cytokines

BACKGROUND

Periodontal disease (PerioD) is a chronic, complex inflammatory condition resulting from the interaction between subgingival dysbiotic bacteria and the host immune response leading to local inflammation. Since periodontal inflammation is characterized by multiple cytokines effects we investigated whether Periodontal Inflamed Surface Area (PISA), a continuous measure of clinical periodontal inflammation is a predictor of composite indexes of salivary cytokines.

METHODS AND FINDINGS

In a cross-sectional study of 67 healthy, well-educated individuals, we evaluated PISA and several cytokines expressed in whole stimulated saliva. Two salivary cytokine indexes were constructed using weighted and unweighted approaches based on a Principal Component Analysis [named Cytokine Component Index (CCI)] or averaging the (standardized) level of all cytokines [named Composite Inflammatory Index (CII)]. In regression analysis we found that PISA scores were significantly associated with both salivary cytokine constructs, (CCI: part R = 0.51, p<0.001; CII: part R = 0.40, p = 0.001) independent of age, gender and BMI showing that single scores summarizing salivary cytokines correlated with severity of clinical periodontal inflammation.

CONCLUSIONS

Clinical periodontal inflammation may be reflected by a single score encompassing several salivary cytokines. These results are consistent with the complexity of interactions characterizing periodontal disease. In addition, Type I error is likely to be avoided.