Pro-inflammatory and anti-inflammatory cytokine expression in post-treatment apical periodontitis

Sodium p-perfluorinated noneoxybenzen sulfonate (OBS) induced neurotoxicity in zebrafish through mitochondrial dysfunction

Sodium p-perfluorous nonenoxybenzene sulfonate (OBS)-one of the main alternatives to perfluorooctane sulfonate-has been increasingly detected in both aquatic environments and human bodies. Therefore, the pathogenic risks of OBS exposure warrant attention, especially its central nervous system toxicity mechanism under long-term exposure. In this study, the effects and mechanisms of OBS on the zebrafish brain at 40 days post exposure were examined. The results demonstrated that at 3.2 μg/L, OBS had no significant effect on the zebrafish brain, but 32 μg/L OBS caused depression or poor social behavior in zebrafish and reduced both their memory and survival ability. These changes were accompanied by histological damage and cell apoptosis. Furthermore, OBS caused the accumulation of excessive reactive oxygen species in the fish brain, leading to oxidative stress and subsequently cell apoptosis. Moreover, an imbalance of both inflammatory factors (IL-6, IL-1β, IL-10, TNF-α, and NF-κB) and neurotransmitters (GABA and Glu) led to neuroinflammation. Additionally, 32 μg/L OBS induced decreases in mitochondrial membrane potential and Na+-K+-ATPase activity, leading to both mitochondrial structural damage and the emergence of mitochondrial autophagosomes, partly explaining the neurotoxicity of OBS. These results help to analyze the target sites and molecular mechanisms of OBS neurotoxicity and provide a basis for the scientific evaluation of its health risks to humans.

Is there any association between the presence of biomarkers and apical periodontitis? A systematic review

This systematic review aimed to verify whether there is evidence of an association between apical periodontitis and the presence of systemic biomarkers. This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses - PRISMA. For this, the acronym PECO was used; population (P) of adult humans exposed (E) to the presence of apical periodontitis, compared (C) to adult humans without apical periodontitis, and the outcome (O) of the presence of biomarkers was observed. The articles were searched in PubMed, Scopus, Web of Science, LILACS, Cochrane Library, OpenGray, and Google Scholar grey databases. Subsequently, studies were excluded based on title, abstract, and full article reading, following the eligibility criteria. The methodological quality of the selected studies was evaluated using the Newcastle-Ottawa qualifier. After exclusion, 656 studies were identified, resulting in 17 final articles that were divided into case-control, cross-sectional, and cohort studies. Eight studies were considered to have a low risk of bias, one had a medium risk of bias, and eight had a high risk of bias. In addition, 12 articles evaluated biomarkers in blood plasma, four evaluated them in saliva, and only one evaluated them in gingival crevicular fluid. The results of these studies indicated an association between apical periodontitis and the systemic presence of biomarkers. These markers are mainly related to inflammation, such as interleukins IL-1, IL-2, and IL-6, oxidative markers, such as nitric oxide and superoxide anions, and immunoglobulins IgG and IgM.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier (CRD42023493959).

Correlation Between Proinflammatory Cytokine Expression and Clinical Data in Apical Granuloma

INTRODUCTION

This study was intended to evaluate the expression of inflammatory cytokines commonly secreted by CD4+ T cells (IL-2, IL-5, IL-17, TGF-β, TNF-α, and IFN-γ) in apical granulomas and correlate with the clinical conditions and time elapsed since root canal treatment.

METHODS

Eighteen biopsy specimens obtained by periradicular surgery of teeth with post-treatment apical periodontitis and diagnosed as apical granuloma were available from the oral pathology laboratory. Silanized slides containing paraffin sections were used for immunohistochemical reactions. Images were analyzed by using an optical microscopy and each slide was subdivided into 5 fields at high magnification.

RESULTS

IFN-γ and TGF-β were the cytokines with the highest expression levels. There were statistically significant differences when comparing IL-2 and IFN-γ (P < .05), and IL-2 and TGF-β (P < .05). Comparison between the detected cytokines and clinical data and time of treatment demonstrated significant correlation (P < .05) between lower expression of IL-2 and the presence of painful symptoms, absence of sinus tract, and treatments performed more than 4 years before. It was also possible to observe a significant correlation between lower expression of IL-5 and treatments performed less than 4 years before (P < .05).

CONCLUSION

IFN-γ and TGF-β were highly expressed in apical granulomas. However, only IL-2 and IL-5 levels were associated with clinical data and time since previous root canal treatment.

Chronic alcohol and nicotine consumption as catalyst for systemic inflammatory storm and bone destruction in apical periodontitis

AIM

To assess the periapical alveolar bone pattern and the serum levels of proinflammatory cytokines, biochemical markers and metabolites in rats subjected to chronic alcohol and nicotine consumption and induced apical periodontitis.

METHODOLOGY

Twenty-eight male Wistar rats were divided into four groups: Control, Alcohol, Nicotine and Alcohol+Nicotine. The alcohol groups were exposed to self-administration of a 25% alcohol solution, while the other groups were given only filtered water. The nicotine groups received daily intraperitoneal injections of a nicotine solution (0.19 μL of nicotine/mL), whereas the other groups received saline solution. Periapical lesions were induced by exposing the pulps of the left mandibular first molars for 28 days. After euthanasia, the mandibles were removed and the percentage bone volume, bone mineral density, trabecular thickness, trabecular separation and trabecular number of the periapical bone were measured using micro-computed tomography images. Serum samples were collected for analysis of proinflammatory cytokines (IL-1β, IL-4, IL-6 and TNF-α), biochemical and metabolomic analysis. Statistical analysis was performed with a significance level of 5%. Nonparametric data were analysed using the Kruskal-Wallis test followed by Dunn's test, while one-way anova followed by Tukey's test was performed for parametric data.

RESULTS

The groups exposed to alcohol or nicotine consumption exhibited an altered bone pattern indicating lower bone density and higher levels of IL-1β, IL-6 and TNF-α compared to the Control group (p < .05). Significant differences were observed among the groups in the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, cholesterol, triglycerides, urea, creatinine, albumin, uric acid, bilirubin and calcium. Metabolomic analysis revealed significant differences in glycine, phosphocholine, lysine, lactate, valine, pyruvate and lipids (CH2 CH2 CO), n(CH2 ) and n(CH3 ). Most of these parameters were even more altered in the simultaneous consumption of both substances compared to single consumption.

CONCLUSION

Alcohol and nicotine chronic consumption altered several metabolic markers, impaired liver and kidney function, increased the production of systemic proinflammatory mediators and harmed the periapical bone microarchitecture in the presence of apical periodontitis. The simultaneous consumption of alcohol and nicotine intensified these detrimental effects.

Does crocin create new hope for the treatment of oral problems? A focus on periodontitis

According to the World Health Organization (WHO) reports, oral health has an indispensable role in the maintenance of human public health. However, oral problems, especially periodontitis, are known as bad players in this issue. Periodontitis, as the most prevalent oral disease, is a type of chronic illness mediated by bacterial pathogens and immune system reactions, which is linked with the destruction of tooth-protecting tissues, such as alveolar bone and periodontal ligament. Periodontitis has a high prevalence (over 40% in the United States) and can be associated with other systemic ailments, for instance, arthritis, osteoporosis, metabolic syndrome, cancer, respiratory diseases, chronic kidney disease, and Alzheimer's disease. The common treatments for periodontitis are classified into invasive (surgical) and noninvasive (antibiotic therapy, scaling, and root planning) methods; however, these therapies have not reflected enough effectiveness for related patients. New documents inform the beneficial effects of plant-based compounds in healing various disorders, like periodontitis. In conjunction with this subject, it has been revealed that crocin, as an active component of saffron, regulates the balance between osteoclasts and osteoblasts and has a stroking role in the accumulation of the most common collagen in teeth and bone (type 1 collagen). Besides, this carotenoid compound possesses anti-inflammatory and anti-oxidative effects, which can be associated with the therapeutic processes of crocin in this oral disease. Hence, this narrative review study was performed to reflect the reparative/regenerative aspects of crocin agonist periodontitis.

Effects of Nd: YAG laser on tumour necrosis factor-alpha, interleukin-1beta and interferon-gamma levels in teeth with apical periodontitis: A clinical study

This study aimed to evaluate the levels of tumour necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and interferon-gamma (IFN-γ) with asymptomatic apical periodontitis (AP). A total of 60 participants were randomly divided into two groups: the conventional irrigation (control) and the Nd: YAG laser irradiation. The interstitial fluids were obtained after root canal cleaning (day 0) and 1 week later (day 7). The TNF-α, IL-1β and IFN-γ levels were assayed using the enzyme-linked immunosorbent assay. The Mann-Whitney U, continuity correction chi-square, Pearson chi-square and Fisher exact tests were used. An increased level of cytokines on day 7 in the control group was observed, without statistically significant differences (p > 0.05). All cytokine levels decreased over time in the laser group. Only the IL-1β level showed a significant difference (p < 0.05). Nd: YAG irradiation has a positive effect on decreasing the proinflammatory cytokine level and may help to control infection in teeth with AP.

Proinflammatory Cytokine Expression in Apical Periodontitis from Diabetic Patients

Diabetes mellitus has been regarded as a condition capable of influencing the evolution of periapical lesions. Therefore, this study evaluated the immunoexpression of IL-1β, TNF-α, and IL-17 in apical periodontitis from type 2 diabetic patients through immunohistochemistry. Twenty-six periapical lesions were selected, and the images obtained through immunohistochemistry reactions were analyzed. The statistical significance was set at p < 0.05. IL-1β expression was considered focal (54%), weak to moderate (38%), and strong (8%) in diabetics, and focal (46%), weak to moderate (31%), and strong (23%), in controls. TNF-α was focal (85%) and weak to moderate (15%) in diabetics, and focal (92%) and weak to moderate (8%), in controls. IL-17 was focal (8%), weak to moderate (46%), and strong (46%) in diabetics, and focal (62%), weak to moderate (8%), and strong (30%), in controls. The quantitative analysis revealed greater expression of IL-17, with a significant difference between IL-17 × IL-1β × TNF-α(p=0.0009) in the diabetic group. The cytokines IL-1β and TNF-α did not express statistical differences between the tested groups. The IL-17 showed higher immunoexpression in the diabetic group (p=0.047), which may suggest higher bone resorption activity in chronic apical periodontitis in this group of patients.

The influence of apical periodontitis on circulatory inflammatory mediators in peripheral blood: A prospective case-control study

AIM

To explore the influence of apical periodontitis (AP) on inflammatory markers in blood of otherwise healthy individuals and to depict the inflammatory profile of the healing after dental extraction.

METHODOLOGY

This is a prospective case-control intervention study, during which, individuals with a diagnosis of AP of one affected tooth were included, along with a control group matched for age and gender. A broad panel of blood inflammatory mediators was examined longitudinally in all subjects during six visits. In the case of the AP subjects, the tooth with AP was extracted at the third visit. Results were analysed by linear regression analyses and linear mixed-model analyses.

RESULTS

A total of 53 subjects were included in the study, 27 with AP and 26 without. Fifteen females and 12 males were included in the AP group, and 14 females and 12 males in the control group. At baseline, granulocyte colony-stimulating factor (p < .001), interleukin (IL)-1β (p = .03) and IL-4 (p = .01) were significantly lower in AP subjects than in controls. Comparison of the differences between baseline and the last visit, i.e. 3 months after the tooth extraction, showed a significant reduction in IL-10 (p = .03) and IL-12p70 (p = .01).

CONCLUSIONS

The immunologic profile of chronic AP in one tooth and its healing profile reveals a systemic low-grade inflammation through compensatory immunosuppression. A larger lesion or multiple lesions could disrupt the balance that the system is trying to maintain, resulting in loss of homeostasis.

Systemic inhibition of 5-lipoxygenase by MK-886 exacerbates apical periodontitis bone loss in a mouse model

BACKGROUND

To investigate if 5-LO selective inhibitor (MK-886) could be used for systemic treatment of experimentally induced apical periodontitis in a mouse model.

METHODS

Twenty-four C57BL/6 mice were used. After coronal opening, a solution containing Escherichia coli LPS (1.0 µg/µL) was inoculated into the root canals of the lower and upper right first molars (n = 72 teeth). After 30 days apical periodontitis was established, and the animals were treated with MK-886 (5 mg/kg), a 5-LO inhibitor, for 7 and 14 days. The tissues were removed for histopathological and histometric analyses, evaluation of osteoclast number and gene expression for receptor activator of nuclear factor kappa-B (Tnfrsf11a), receptor activator of nuclear factor kappa-B ligand (Tnfsf11), osteoprotegerin (Tnfrsf11b), tartrate-resistant acid phosphatase (Acp5), matrix metalloproteinase-9 (Mmp9), cathepsin K (Ctsk) and calcitonin receptor (Calcr). Statistical data analysis was performed using Kruskal Wallis followed by Dunn's tests (α = 0.05).

RESULTS

Administration of MK-886 for 7 days exerted no effect on apical periodontitis progression compared to LPS inoculation without treatment (p = 0.3549), while treatment for 14 days exacerbated bone loss (p < 0.0001). Administration of MK-886 enhanced osteoclastogenesis signaling and osteoclast formation within 7 days (p = 0.0005), but exerted no effect at 14 days (p > 0.9999). After 7 days of treatment, MK-886 induced mRNA expression for Acp5 (p = 0.0001), Calcr (p = 0.0003), Mmp9 (p = 0.0005) and Ctsk (p = 0.0008), however no effect in those gene expression was observed after 14 days (p > 0.05).

CONCLUSION

Systemic treatment with MK-886 exacerbated LPS-induced apical periodontitis in a mouse model.

RESULTS OF INFLAMMATORY AND IMMUNOLOGICAL PARAMETERS OF THE ORAL CAVITY AFTER CYSTECTOMY WITH DIFFERENT METHODS OF CONNECTING THE EDGES OF THE OPERATED AREA

OBJECTIVE

The aim: To analyze the results of inflammatory and immunological parameters of the oral cavity after cystectomy with different methods of connecting the edges of the operated area.

PATIENTS AND METHODS

Materials and methods: The research was conducted in 87 patients who sought surgical treatment of odontogenic cysts of the jaws. Patients were divided into groups depending on the method of wound closure after surgery. We analyzed the results of laboratory tests (leukocytes, ESR, IL-1β, IL-6, TNF-α, IL-8, NO synthase, MMP-9).

RESULTS

Results: The analysis of the effectiveness of using different methods of approximation of the oral mucosa wound on inflammatory and immunological pa¬rameters showed that when using welding of the edges of the operated area using the EKVZ-300 "Patonmed" apparatus, we get positive results of laboratory indicators of inflammatory markers faster (leukocyte counts are normal on day 30, ESR, IL-1β - on the 14th day, TNF-α - on the 7th day, IL-6, IL-8, NO synthase, MMP-9 - on the 30th day), that is, healing in such patients is faster than in patients with wound closure with classic suture material or laser.

CONCLUSION

Conclusions: When comparing the methods of approximation of postoperative oral mucosa wounds by different methods, based on the results of these inflammatory and immunological parameters, the best results were obtained when using electric welding of tissues. Further research and use of the proposed method will facilitate and shorten the rehabilitation period of patients after surgery.

Genetic, Cellular and Molecular Aspects involved in Apical Periodontitis

The development, establishment and repair of apical periodontitis (AP) is dependent of several factors, which include host susceptibility, microbial infection, immune response, quality of root canal treatment and organism's ability to repair. The understanding of genetic contributions to the risk of developing AP and presenting persistent AP has been extensively explored in modern Endodontics. Thus, this article aims to provide a review of the literature regarding the biochemical mediators involved in immune response signaling, osteoclastogenesis and bone neoformation, as the genetic components involved in the development and repair of AP. A narrative review of the literature was performed through a PUBMED/MEDLINE search and a hand search of the major AP textbooks. The knowledge regarding the cells, receptors and molecules involved in the host's immune-inflammatory response during the progression of AP added to the knowledge of bone biology allows the identification of factors inherent to the host that can interfere both in the progression and in the repair of these lesions. The main outcomes of studies evaluated in the review that investigated the correlation between genetic polymorphisms and AP in the last five years, demonstrate that genetic factors of the individual are involved in the success of root canal treatment. The discussion of this review gives subsides that may help to glimpse the development of new therapies based on the identification of therapeutic targets and the development of materials and techniques aimed at acting at the molecular level for clinical, radiographic and histological success of root canal treatment.

Postbiotics Enhance NK Cell Activation in Stress-Induced Mice through Gut Microbiome Regulation

Recent studies have revealed that probiotics and their metabolites are present under various conditions; however, the role of probiotic metabolites (i.e., postbiotics in pathological states) is controversial. Natural killer (NK) cells play a key role in innate and adaptive immunity. In this study, we examined NK cell activation influenced by a postbiotics mixture in response to gut microbiome modulation in stress-induced mice. In vivo activation of NK cells increased in the postbiotics mixture treatment group in accordance with Th1/Th2 expression level. Meanwhile, the Red Ginseng treatment group, a reference group, showed very little expression of NK cell activation. Moreover, the postbiotics mixture treatment group in particular changed the gut microbiome composition. Although the exact role of the postbiotics mixture in regulating the immune system of stress-induced mice remains unclear, the postbiotics mixture-induced NK cell activation might have affected gut microbiome modulation.

Correlation between Transforming Growth Factor-β and Periapical Lesions in Patients with Chronic Apical Periodontitis

Objective

To examine the expression of transforming growth factor-β (TGF-β) in the periapical granulation tissue and serum of patients with chronic apical periodontitis and to conduct immunohistochemical analysis so as to explore the relationship between TGF-β and the degree of periapical lesions.

Methods

Periapical granulation tissues of 20 cases of chronic apical periodontitis were collected as the experimental group. Healthy gingival tissues without eruption of third molars of 5 cases were collected as the control group. Immunohistochemistry, enzyme-linked immunosorbent assay, and real-time PCR (RT-PCR) were utilized to determine the expression of TGF-β mRNA and protein, and the difference in the expression of TGF-β was compared between groups. In the experimental group, oral CBCT was taken to measure the periapical bone resorption area. Spearman's correlation method was applied to analyze the correlation between TGF-β protein and gene expression levels and periapical bone resorption area.

Results

Immunohistochemistry and enzyme-linked immunosorbent assay demonstrated that the expression of TGF-β protein in chronic apical periodontitis tissue and serum was higher than that in the controls (P < 0.05). RT-PCR revealed that the expression of TGF-β mRNA was higher in chronic apical periodontitis tissue than that of the controls (P < 0.05). Spearman's correlation analysis showed that in the experimental group, the mRNA expression of TGF-β was positively correlated with the periapical bone resorption area (P < 0.01), and the protein expression level was not correlated with the periapical bone resorption area (P < 0.05).

Conclusion

The increased expression of TGF-β in the periapical granulation tissue and serum of patients with chronic apical periodontitis has a certain correlation with the progression of periapical periodontitis. The correlation between TGF-β at the mRNA level and the degree of early stage disease as well as the high expression of TGF-β in inflammatory cells in immunohistochemistry have confirmed that TGF-β promotes bone resorption in early periapical periodontitis, and its mechanism of action deserves further investigation.

Ex vivo study of IL-6 expression and function in immune cell subsets from human periapical lesions

AIM

Even though IL-6 is a key inflammatory cytokine in periapical lesions (PLs), its function in stable periapical disease is unknown. Therefore, the aim of this study was to investigate following: first, the ex vivo production of IL-6 by clinically different PLs; next, subsets of immune cells expressing IL-6 in PLs according to their inflammatory status and finally, modulatory effect of IL-6 on T-cell cytokine production in cell cultures.

METHODOLOGY

Inflammatory cells were isolated from a total of 95 human PLs. Detection of IL-6⁺ cells within the myeloid and lymphoid populations was performed by multicolour flow cytometry. ELISA and FlowCytomix Microbeads Assay were used to measure cytokine levels in culture supernatants. To study the role of IL-6 in PLs, mononuclear cells (MNC) from symptomatic (Sy) or asymptomatic (Asy) PLs were treated with IL-6 or Tocilizumab, an IL-6R blocking antibody. The differences between groups were tested by unpaired t-test, Mann-Whitney or Friedman tests.

RESULTS

The levels of IL-6 in PL MNC culture supernatants were significantly higher compared to total PL cells and PL granulocytes (p<0.001). MNC from Sy PLs produced significantly hihger levels of IL-6 than MNC from Asy PLs (p<0.001). Flow cytometry analysis showed that NKT cells, CD8⁺ T cells and M2 macrophages (MØ), were dominant IL-6⁺ cells, in contrast to CD4⁺ T cells. However, CD8⁺ and CD4⁺ T cells contributed the most to IL-6 production. IL-6^hi producing MNC cultures had higher levels of Th1 (IFN-γ), Th17 (IL-17A), Tfh (IL-21) and RANKL, whereas Th2 (IL-4) and Tregs cytokines (IL-10, TGF-β) were lower, compared to IL-6^low producing cultures. Exogenous IL-6 stimulated 17A, IL-21 and RANKL, independently of PL activation status, but decreased IFN-γ, IL-4 and IL-33 levels in IL-6^hi producing cultures. Tocilizumab increased IL-10 and TGF-β in IL-6^low producing cultures. All differences were p<0.05.

CONCLUSIONS

Most immune cells from Sy PLs expressed higher levels of IL-6 compared to Asy PLs, which correlated with IL-6 production in culture. Analysis of cytokines suggested a dominant pro-inflammatory T-cell response and osteodestructive function of IL-6 in PLs judging by Th17/Tfh cell activation, Tregs inhibition and increased RANKL/OPG ratio. Excessive IL-6 production decreased Th1/Th2 responses.

Virgin Coconut Oil as a New Concept for Periodontal Tissue Regeneration via Expressions of TNF-α and TGF-β1

Background

Virgin coconut oil is a natural product from coconut that has many benefits such as antibacterial, anti-inflammatory, and antioxidant. Inflammatory disease of the periodontal tissues has a high prevalence worldwide. The main etiology of periodontitis plaque of biofilm contains colonies of pathogenic microorganisms. The occurrence of inflammation in the periodontal tissue stimulates the release of inflammatory mediators, such as TNF-α and TGF-β. Treatment for periodontitis can be performed starting from initial therapy and usually accompanied by additional therapy such as local drug delivery. VCO can be used as an alternative to antibiotics.

Objective

To determine the effectiveness of VCO gel on periodontal tissue regeneration materials through the expression of TNF-α and TGF-β1.

Methods

This is an experimental laboratory with a posttest-only control group design. VCO was made from grated fresh coconut and then mixed with NaCMC to obtain gel viscosity. The subjects of this study were 30 male periodontitis-induced Wistar rats by injecting Porphyromonas gingivalis into the gingival sulcus. Wistar rats were then divided into 3 groups. On the 7th and 14th days, the rats were sacrificed and the jaw was sampled to determine the amount of TNF-α and TGF-β1 expression in the regenerative process of periodontal tissue.

Result

The amount of TNF-α and TGF-β1 increased significantly in the treatment group, but not as much as the increase in the positive control and negative control groups.

Conclusion

VCO gel can affect the expression of TNF-α and TGF-β1 in the regeneration process of periodontal tissue in periodontitis-induced rats.

Aging as a Risk Factor on the Immunoexpression of Pro-Inflammatory IL-1β, IL-6 and TNF-α Cytokines in Chronic Apical Periodontitis Lesions

Persistent inflammatory responses in the elderly may act as modifiers on the progression and repair of chronic apical periodontitis lesions (CAPLs). While the involvement of IL-1β, IL-6 and TNF-α in inflammatory responses and, particularly, in CAPL has been documented, their expression in elderly patients needs to be further characterized. Therefore, the purpose of this study was to evaluate and compare the expressions of pro-inflammatory cytokines in CAPL from elderly individuals with young/middle-aged individuals. Thirty CAPL (15 cysts and 15 granulomas) from elderly patients (>60 years) and 30 CAPL (15 cysts and 15 granuloma) from young/middle-aged individuals (20–56 years) were selected. Immunohistochemical reactions were performed against IL-1β, IL-6 and TNF-α. The slides were subdivided into five high-magnification fields and analyzed. The number of positive stains was evaluated for each antibody. There was no significant difference between the cytokines when the cysts and granuloma were compared in the two groups. In the young/middle-aged, only IL-1β showed a difference and was significantly higher in granulomas (p = 0.019). CAPL pro-inflammatory cytokine levels in the elderly were significantly higher than in young/middle-aged individuals (p < 0.05). The pro-inflammatory cytokines IL-1β, IL-6 and TNF-α were significantly higher in CAPL in the elderly compared with the young/middle-aged group. Further elaborate research studies/analyses to elucidate the reasons for and consequences of inflammation in the elderly are recommended.

Periodontal Inflammation and Systemic Diseases: An Overview

Periodontitis is a common inflammatory disease of infectious origins that often evolves into a chronic condition. Aside from its importance as a stomatologic ailment, chronic periodontitis has gained relevance since it has been shown that it can develop into a systemic condition characterized by unresolved hyper-inflammation, disruption of the innate and adaptive immune system, dysbiosis of the oral, gut and other location's microbiota and other system-wide alterations that may cause, coexist or aggravate other health issues associated to elevated morbi-mortality. The relationships between the infectious, immune, inflammatory, and systemic features of periodontitis and its many related diseases are far from being fully understood and are indeed still debated. However, to date, a large body of evidence on the different biological, clinical, and policy-enabling sources of information, is available. The aim of the present work is to summarize many of these sources of information and contextualize them under a systemic inflammation framework that may set the basis to an integral vision, useful for basic, clinical, and therapeutic goals.

Plasma Rich in Growth Factors in the Treatment of Endodontic Periapical Lesions in Adult Patients: A Narrative Review

Platelet concentrates have been widely used in regenerative medicine, including endodontics. The aim of this manuscript was to assess critically the efficacy of PRF in the treatment of endodontic periapical lesions in adult patients on the basis of the literature. The PICO approach was used to properly develop literature search strategies. The PubMed database was analyzed with the keywords: "((PRP) OR (PRF) OR (PRGF) OR (CGF)) AND (endodontic) AND ((treatment) OR (therapy))". After screening of 155 results, 14 articles were included in this review. Different types of platelet concentrates are able to stimulate the processes of proliferation and differentiation of mesenchymal stem cells. Platelet rich fibrin (PRF) releases growth factors for at least 7 days at the application site. Growth factors and released cytokines stimulate the activity of osteoblasts. Moreover, the release of growth factors accelerates tissue regeneration by increasing the migration of fibroblasts. It was not possible to assess the efficacy of PRF supplementation in the treatment of endodontic periapical lesions in permanent, mature teeth with closed apexes, due to the lack of well-designed scientific research. Further studies are needed to analyze the effect of PRF on the healing processes in the periapical region.

Comparison of Biocompatibility of Calcium Silicate-Based Sealers and Epoxy Resin-Based Sealer on Human Periodontal Ligament Stem Cells

The aim of this study was to evaluate the biocompatibility of calcium silicate-based sealers (CeraSeal and EndoSeal TCS) and epoxy resin-based sealer (AH-Plus) in terms of cell viability, inflammatory response, expression of mesenchymal phenotype, osteogenic potential, cell attachment, and morphology, of human periodontal ligament stem cells (hPDLSCs). hPDLSCs were acquired from the premolars (n = 4) of four subjects, whose ages extended from 16 to 24 years of age. Flow cytometry analysis showed stemness of hPDLSCs was maintained in all materials. In cell viability test, AH-Plus showed the lowest cell viability, and CeraSeal showed significantly higher cell viability than others. In ELISA test, AH-Plus showed higher expression of IL-6 and IL-8 than calcium silicate-based sealers. In an osteogenic potential test, AH-Plus showed a lower expression level than other material; however, EndoSeal TCS showed a better expression level than others. All experiments were repeated at least three times per cell line. Scanning electronic microscopy studies showed low degree of cell proliferation on AH-Plus, and high degree of cell proliferation on calcium silicate-based sealers. In this study, calcium silicate-based sealers appear to be more biocompatible and less cytotoxic than epoxy-resin based sealers.

Treatment with Luteolin Improves Lipopolysaccharide-Induced Periodontal Diseases in Rats

Periodontitis is a dental disease that produces the progressive destruction of the bone surrounding the tooth. Especially, lipopolysaccharide (LPS) is involved in the deterioration of the alveolar bone, inducing the release of pro-inflammatory mediators, which cause periodontal tissue inflammation. Luteolin (Lut), a molecule of natural origin present in a large variety of fruits and vegetables, possess beneficial properties for human health. On this basis, we investigated the anti-inflammatory properties of Lut in a model of periodontitis induced by LPS in rats. Animal model predicted a single intragingival injection of LPS (10 μg/μL) derived from Salmonella typhimurium. Lut administration, was performed daily at different doses (10, 30, and 100 mg/kg, orally), starting from 1 h after the injection of LPS. After 14 days, the animals were sacrificed, and their gums were processed for biochemical analysis and histological examinations. Results showed that Lut (30 and 100 mg/kg) was equally able to reduce alveolar bone loss, tissue damage, and neutrophilic infiltration. Moreover, Lut treatment reduced the concentration of collagen fibers, mast cells degranulation, and NF-κB activation, as well as the presence of pro-inflammatory enzymes and cytokines. Therefore, Lut implementation could represent valid support in the pharmacological strategy for periodontitis, thus improving the well-being of the oral cavity.

Can Resveratrol Treatment Control the Progression of Induced Periodontal Disease? A Systematic Review and Meta-Analysis of Preclinical Studies

Resveratrol is an anti-inflammatory compound found in several foods. Periodontal disease (PD) is associated to other systemic diseases, and inflammation may be responsible for the association. Consequently, controlling inflammation not only may benefit oral health but also may assist with the management of other chronic inflammatory conditions. We aimed to investigate the effects of resveratrol administration on PD control in preclinical studies. A systematic search was performed for scientific articles using both electronic databases and a manual search using combinations of the following keywords: “resveratrol” OR “3,5,4′-trihydroxystilbene” AND “periodontal disease” OR “periodontitis” OR “gingivitis”. Only in vivo original studies investigating resveratrol treatment on experimental animal models of PD were selected. A quality assessment of the studies was performed using the Animal Research Reporting In Vivo Experiment (ARRIVE) guidelines, and the risk of bias was assessed using the Syrcle tool. The search returned 570 articles, and 11 matched the inclusion criteria. A meta-analysis showed that resveratrol treatment attenuated alveolar bone loss (τ² = 0.0041; 95% CI: −0.14; −0.04). The ARRIVE criteria reported a good quality of studies in general (mean score 28.5 ± 2.5). However, five Syrcle domains indicated a high risk of bias or did not present information clearly. We concluded that, in preclinical studies, resveratrol treatment prevented PD progression.