Periodontal disease and its impact on general health in Latin America. Section V: Treatment of periodontitis

Role of periodontal treatment in pregnancy gingivitis and adverse outcomes: a systematic review and meta-analysis

BACKGROUND

Pregnancy gingivitis is a common oral health issue that affects both maternal and fetal health. This study aims to evaluate the effectiveness of periodontal treatment in preventing pregnancy gingivitis, preterm birth, and low birth weight through a systematic review and meta-analysis of randomized controlled trials (RCTs).

METHODS

A systematic review and meta-analysis were conducted following PRISMA guidelines. A comprehensive literature search was performed across CINAHL, Scopus, Cochrane, and PubMed/Medline databases from 2000 to the present. Study selection and data extraction were independently carried out by two reviewers. Statistical analyses, including heterogeneity tests, sensitivity analysis, and publication bias assessment, were conducted using RevMan 5.4 and R software.

RESULTS

A total of 13 studies were included. The meta-analysis indicated that periodontal treatment might have a potential effect on preventing pregnancy gingivitis, but this was not statistically significant (OR = 0.85, 95% CI [0.68, 1.06], I2 = 51%). Subgroup analysis revealed that periodontal treatment significantly reduced the rates of preterm birth and low birth weight in lower-quality studies, but no significant effects were observed in higher-quality studies. Sensitivity analysis and publication bias tests confirmed the stability and reliability of the results.

CONCLUSION

While lower-quality studies suggest that periodontal treatment may positively impact pregnancy gingivitis, preterm birth, and low birth weight, these effects were not supported by higher-quality evidence. Further well-designed RCTs are needed to confirm these findings and ensure their reliability. Periodontal treatment could potentially be considered as part of prenatal care to improve maternal oral health and pregnancy outcomes.

Is there a relationship between periodontal conditions and asprosin levels in gingival crevicular fluid, saliva and serum?

OBJECTIVES

This study aimed to investigate the presence of asprosin hormone in the biological fluids of patients with periodontal inflammation and compare it to those with periodontal healthy.

MATERIALS AND METHODS

Seventy-five individuals between the ages of 18 to 45, 25 periodontal healthy, 25 with gingivitis, and 25 with periodontitis, were included in the study. Gingival crevicular fluid (GCF), blood serum and saliva were obtained from individuals in each group. Tumour necrosis factor-alpha (TNF-α) and asprosin levels in these fluids were determined using the ELISA. Clinical periodontal measurements were recorded and body mass index was calculated. One-way ANOVA and Bonferroni tests were performed for statistical analysis. Spearman test was used to evaluate correlations. The significance level was determined as p < 0.05.

RESULTS

Body mass index values were not different between the groups (p = 0.446). Clinical periodontal measurements were significantly higher in the periodontitis group. Concentrations of TNF-α in GCF, serum and saliva increased significantly in patients with gingivitis and periodontitis (p < 0.001). The higher TNF-α levels were obtained in patients with periodontitis than in individuals with gingivitis (p = 0.001). While asprosin levels were found to be significantly higher in patients with gingivitis and periodontitis (p < 0.001), no significant difference was observed between both groups (p > 0.05). GCF-asprosin levels were positively correlated with the concentrations in serum and saliva in all individuals included in the study (p < 0.05).

CONCLUSION

The periodontal inflammation caused an increase in asprosin hormone in gingival crevicular fluid independently of the type of periodontal disease.

TRIAL REGISTRATION

This study is registered with number of "NCT06627972" in ClinicalTrials.gov website from the date of October 3, 2024.

Potential of mir-299-5p to modulate LPS-induced inflammation and osteogenic differentiation of periodontal stem cells by targeting PUM2

BACKGROUND

Periodontitis is a prevalent oral disease that significantly impacts human quality of life. This study aimed at the influence of microRNA-299-5p (miR-299-5p) on regulating lipopolysaccharide (LPS)-induced osteogenic differentiation of periodontal ligament stem cells (PDLSCs).

METHODS

The 105 periodontitis patients and 102 healthy periodontal volunteers (HC) were recruited with their clinical baseline data. miR-299-5p expression in saliva was measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR). To identify the target relationship between miR-299-5p and pumilio RNA-binding family member 2 (PUM2), the dual luciferase reporter gene was explored. PDLSCs were treated with LPS and subjected to osteogenic differentiation induction. The secretion of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β) was determined by enzyme-linked immunosorbent assay. mRNA expression of runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), and osteocalcin (OCN) was detected by qRT-PCR.

RESULTS

miR-299-5p expression was markedly reduced in periodontitis patients' saliva and negatively correlated with patients' attachment loss, bleeding index, plaque index, probing pocket depth, and TNF-α, IL-6, and IL-1β levels. miR-299-5p could be well distinguished between periodontitis and HC. LPS induction dramatically stimulated the secretion of inflammatory factors and inhibited the differentiation of PDLSCs, which was counteracted by miR-299-5p overexpression. miR-299-5p was detected to target PUM2, which could exacerbate the inflammatory condition of PDLSCs and lead to differentiation defects.

CONCLUSIONS

miR-299-5p has emerged as a promising diagnostic marker for periodontitis and may attenuate inflammation and contribute to osteogenic differentiation in PDLSCs cells by targeting PUM2.

Subgingival Delivery of Statins as an Adjunct in the Non-Surgical Treatment of Periodontitis: A Systematic Review

BACKGROUND/OBJECTIVES

The gold standard in the non-surgical treatment of periodontitis is scaling and root planning (SRP). In recent years, studies have emerged suggesting additional clinical benefits from the use of statins as an adjunct to classical periodontal disease treatment. The aim of the present study was to review the relevant literature relating to the subgingival use of statins as an adjunctive treatment to the classical, non-surgical treatment of periodontitis, with a particular focus on groups with general factors that may affect the outcome of treatment.

METHODS

The authors conducted a systematic review following the PRISMA 2020 guidelines. The electronic literature search conducted included the MEDLINE (PubMed) database, Web of Science, Scopus, and Google Scholar from 1 January 2012 to 14 June 2024. The keywords used for the PubMed search were determined with the help of the MeSH Browser Tool and were as follows: Periodontitis [Mesh] AND Statin [Mesh] OR Simvastatin [Mesh] OR Atorvastatin [Mesh] or Rosuvastatin Calcium [Mesh]. Based on the authors' inclusion and exclusion criteria, 20 results were included in the review, out of 937.

RESULTS

The improvement was more pronounced in patients without systematic diseases compared to those with type II diabetes and in non-smokers compared to smoking patients. Greater improvements in clinical and radiological parameters were seen in patients diagnosed with aggressive periodontitis compared to patients with chronic periodontitis.

CONCLUSIONS

This literature review led the authors to the conclusion that statins applied locally might be competent agents for improving the therapeutic outcomes of SRP.

DLK1 regulates periodontal inflammation by inhibiting NF-κB p65 and JNK signaling pathways

The roles and molecular mechanisms of Delta-like 1 (DLK1) in periodontitis remain largely unknown. Here, we investigated the expression of DLK1 and NF-κB p65 in Porphyromonas gingivalis (Pg.)-induced periodontitis in vivo. Periodontal inflammation and alveolar bone resorption were analyzed using western blotting, micro-computed tomography, TRAP staining, immunohistochemistry, and immunofluorescence. Raw246.7 cells were stimulated with 1 μg/ml Porphyromonas gingivalis lipopolysaccharide (Pg.LPS) to assess DLK1 expression in vitro. DLK1 overexpression was achieved, and transfection efficiency was confirmed using western blotting and immunofluorescence. The NF-κB and MAPK pathways were activated by treating cells with 1 μg/ml Pg.LPS to explore related mechanisms. Compared with normal tissues, both DLK1 and NF-κB p65 expression increased in periodontitis gingival tissues. DLK1-positive expression was observed in inflammatory infiltrating cells and osteoclasts in the marginal lacunae of the alveolar bone. DLK1 expression in CD68-positive macrophages was detected by immunofluorescence. However, DLK1 expression in Raw246.7 cells decreased after Pg.LPS stimulation and during osteoclast differentiation. DLK1 levels negatively correlated with TNF-α, IL-1β, and NFATC1. Increased DLK1 in Raw246.7 cells further inhibited COX2 and iNOS expressions. Mechanistically, DLK1 overexpression down-regulated NF-κB p65 and JNK levels. In summary, these findings suggest that DLK1 overexpression inhibits periodontal inflammation through the NF-κB p65 and JNK pathways. Interventions targeting increased DLK1 levels may have therapeutic implications for periodontitis.

Humic Acid Derived from Agricultural Biomass Mitigates Alveolar Bone Loss and Modulates Systemic Inflammatory Cytokines in Rats with Periodontitis

BACKGROUND

Humic acid (HA) is a bioproduct that can be extracted from different sources and has anti-inflammatory properties that have been little explored in the treatment and prevention of Periodontal Disease (PD). Thus, we aimed to investigate the effects of oral administration of HA on the progression of PD in rats.

METHODS

Twenty-four male Wistar rats were distributed into three experimental groups (Control/ Sham, PD, and PD + HA). HA was administered by gavage (80 mg/kg/day) for 28 days, and PD was induced 14 days after the beginning of treatment. Bone loss, bone topography, and surface elemental composition were analyzed. Circulating IL1-beta, TNF-alpha, and IL-10 levels were evaluated through Enzyme-Linked Immunosorbent Assay (ELISA).

RESULTS

The animals treated with HA showed lower bone loss (p < 0.05). Calcium and phosphorus levels on the alveolar bone surface were lower in the PD group (p < 0.05) compared to the control group, whereas the animals treated with HA exhibited attenuation in this loss (p < 0.05). The animals treated with HA showed reduced TNF-alpha, IL1-beta, IL-10, and the TNF-alpha/IL-10 ratio compared to those with PD (p < 0.05).

CONCLUSION

Treatment with HA attenuated the parameters of alveolar bone loss and modulated systemic inflammatory parameters in rats with ligature-induced PD.

Periodontitis and chronic kidney disease: A bidirectional relationship based on inflammation and oxidative stress

Chronic kidney disease (CKD) and chronic periodontitis (CP) are prevalent conditions which significantly impact public health worldwide. Both diseases share inflammatory and oxidative stress mechanisms, an indication of a likely bidirectional relationship. This editorial explored the association between CKD and CP by highlighting common inflammatory mechanisms and recent research findings that address this interrelationship. Through reviews of recent studies, we discussed how periodontal bacteria may activate systemic immune responses that affect both periodontal and renal tissues. Additionally, meta-analysis data indicated an increased risk of CKD development in patients with CP, and vice versa. The results suggest the need for more rigorous research in the future in order to address the confounding factors and evaluate specific periodontal health interventions and their direct effects on kidney function. We emphasized the importance of comprehensive and multidisciplinary care for the improvement of the overall health of patients affected by CP and CKD.

Flowable Oxygen-Release Hydrogel Inhibits Bacteria and Treats Periodontitis

Periodontitis, the chronic inflammation of the periodontal tissues caused by bacteria in plaque, is the leading cause of tooth loss in adults in the world. Currently, periodontitis is effectively treated with mechanical cleaning and the use of antibiotics. However, these treatments only temporarily remove plaque, which can rapidly proliferate and multiply in periodontal pockets over time. Although antibiotics have positive antimicrobial effects, their long-term use increases the risk of the emergence of drug-resistant strains. The emergence of resistant strains reduces the effectiveness of periodontitis treatment and makes the disease more difficult to control. Herein, this paper reports the development of an injectable self-oxygenating composite hydrogel for periodontal therapy, which was produced by loading CaO2 nanoparticles and ascorbic acid into an injectable alginate hydrogel. CaO2 can improve the periodontal pocket microenvironment by reacting with water to generate oxygen, calcium ions can be used as a bone regeneration material, and ascorbic acid protects cells. The authors further showed that the composite hydrogel inhibited growth and colonization of anaerobic bacteria, reduced the degree of inflammation, and promoted alveolar bone regeneration. In conclusion, these findings suggest that the composite hydrogel can be used as a biocompatible, convenient, and effective method for periodontitis treatment.

The Study of Chemical Constituents and Metabolite Profiles of Chitong Xiaoyanling Granules in Normal and Periodontitis Model Rats Based on Ultra-High-Performance Liquid Chromatography-Quadrupole Time-of-Flight-Tandem Mass Spectrometry Analysis

Periodontitis is a chronic inflammation of the periodontal support tissues. The typical symptoms of periodontitis are inflammation and alveolar bone resorption. Chitong Xiaoyanling Granules (CXG) is composed of 10 Chinese herbs, which have the efficacy of dispersing wind, clearing heat, cooling blood, and relieving pain. CXG is clinically used for the treatment of periodontitis and other diseases, with remarkable efficacy and broad application prospects. However, due to the lack of systematic research on its chemical constituents and metabolites, it is of great significance to characterize the various chemical components and metabolites of CXG. In this study, ultra-high-performance liquid chromatography-quadrupole time-of-flight-tandem mass spectrometry analysis was used to identify the chemical constituents and metabolites of CXG, and the differences in metabolite profiles between normal and model rats were compared. A total of 147 compounds were identified in CXG, including 53 flavonoids, 28 terpenoids, seven chromones, eight coumarins, eight organic acids, 12 phenols, 10 alcohols, nine sugars, and 12 others. In normal and model rats, 191 and 179 CXG-related xenobiotics were detected respectively. In conclusion, a rapid and accurate identification method was used to identify the chemical components and metabolites of CXG, which laid a foundation for the study of the quality control and pharmacological mechanisms of CXG.

Correlation of serum vitamin D and IL-8 to stages of periodontitis: a case-control analysis

OBJECTIVES

The current literature lacks the correlation between serum levels of vitamin D and interleukin-8 (IL-8) to the stages of periodontitis. The present research objectives are to evaluate the serum levels of vitamin D and IL-8 in periodontitis participants and healthy controls and to measure their correlation with the stages of periodontitis.

METHODS

The current case-control study was conducted on patients with periodontitis and healthy controls. After obtaining a questionnaire from the participants, the following clinical parameters were measured; periodontal probing depth (PPD), clinical attachment loss (CAL), plaque index (PI), gingival index (GI), bleeding on probing (BOP), and tooth count. The serum levels of vitamin D and IL-8 were measured using ELISA kits. Then, we measured the correlation of the stages of periodontitis with the serum levels of vitamin D and IL-8.

RESULTS

Ninety-eight participants; 52 with periodontitis and 46 healthy controls were included. The patients with periodontitis showed a significantly lower level of vitamin D, higher PPD, CAL, BOP, and lower number of teeth than the controls. In addition, serum vitamin D significantly correlated with the stages of periodontitis. Serum IL-8 showed no significant difference between the study and control groups while it does not significantly correlate with the stages of periodontitis.

CONCLUSION

The current study's findings suggest a potential association between serum level of vitamin D with severity of periodontitis which necessitates screening vitamin D status in patients with periodontitis and investigating the possibility of vitamin D supplementation in decreasing the progression of periodontitis.

Fusobacterium nucleatum-infected periodontitis promotes renal interstitial fibrosis in rats through the TGF-β/SMAD2/3 and β-catenin signaling pathways

OBJECTIVES

Periodontitis is associated with Fusobacterium nucleatum (F.n) infection. Although the colonization of renal tissue by F.n is well documented, its specific role in kidney disease has yet to be determined. This study aimed to investigate the potential association between F.n-induced periodontitis and renal interstitial fibrosis.

METHODS

The rat gingival sulcus was injected with F.n suspension, while the control group (NC) was injected with PBS. The levels of total protein (TP), albumin (ALB), creatinine, and urea nitrogen (BUN) in rat serum and/or urine were quantified using the appropriate kits. Renal interstitial fibrosis and epithelial-mesenchymal transition (EMT) were evaluated in rats using Masson staining, Periodic Schiff-Methenamine (PASM) staining, and immunohistochemical staining. The levels of fibrosis- and EMT-related proteins and the TGF-β/SMAD2/3 and β-catenin signaling pathways were determined using Western blot analysis. F.n in the kidney tissues was quantitatively determined using bacterial 16S rRNA technology.

RESULTS

Serum levels of TP, ALB, creatinine, and BUN were not significantly decreased in F.n-infected rats with periodontitis. The levels of creatinine and ALB in the urine were not statistically different between two groups. Masson and PASM staining showed that F.n-induced periodontitis could promote renal interstitial fibrosis in rats. The levels of collagen I, fibronectin (FN), vimentin, and α-SMA were upregulated in the kidney tissues of rats with F.n-induced periodontitis and in F.n-treated HK-2 cells. However, E-cadherin levels were reduced. F.n promoted renal interstitial and HK-2 cell fibrosis in rats by modulating the TGF-β/SMAD2/3 and β-catenin signaling pathways. F.n colonization increased renal interstitial fibrosis in rats.

CONCLUSION

F.n-induced periodontitis promoted EMT by activating the TGF-β/SMAD2/3 and β-catenin signaling pathways, thus promoting renal interstitial fibrosis in rats.

Microbiological profile of patients with generalized gingivitis undergoing periodontal therapy and administration of Bifidobacterium animalis subsp. lactis HN019: A randomized clinical trial

OBJECTIVE

To evaluate the adjunctive use of the probiotic Bifidobacterium animalis subsp. lactis HN019 (B. lactis HN019) to conventional therapy on clinical and microbiological parameters in patients with generalized gingivitis.

METHODS

Sixty systemically healthy individuals with untreated generalized gingivitis were submitted to periodontal therapy and allocated to receive Placebo (n = 30) or Probiotic (n = 30) lozenges, twice a day for 8 weeks. Bleeding on Marginal Probing (BOMP) was evaluated at baseline, after 2 and 8 weeks. Supra and subgingival biofilm were obtained at baseline and 8 weeks post-therapy for analyses by 16S rRNA gene sequencing. Differences between therapeutic groups were analyzed by non-parametric tests (p<0.05).

RESULTS

The Placebo and Probiotic groups showed a significant reduction in BOMP at 8 weeks compared to baseline (p<0.05). The Probiotic group had a lower percentage of BOMP when compared with the Placebo group at 8 weeks (p<0.0001). Alpha and beta-diversity showed no statistical significance between groups and time points. At phylum level, no significant differences were observed between groups and time points. At genus level, an increase in the relative abundances of Bergeyella and Corynebacterium were significantly associated with a greater reduction in bleeding in the Placebo group and with less reduction in bleeding in the Probiotic group, respectively. At species level, Schaalia spp., Streptococcus gordonii, and Leptotrichia wadei increased in Placebo and decreased in the Probiotic group after treatment. Granulicatella adiacens decreased significantly after the probiotic therapy, while Saccharibacteria (TM7) spp., Solobacterium moorei, and Catonella morbi increased significantly. In the Placebo group, Bergeyella sp. HMT-322 was associated with a greater percentage of reduction in bleeding. In both groups, Actinomyces species were related to less reduction in bleeding.

CONCLUSION

The adjuvant use of B. lactis HN019 alongside conventional therapy enhanced the reduction in BOMP and promoted greater changes in the microbiological profile of patients with generalized gingivitis.

TRIAL REGISTRATION

The study was registered at Brazilian Clinical Trials Registry (ReBEC; protocol number: RBR-59v2yb).

Assessing the impact of systemic conditions on periodontal health in Malaysian population: a retrospective study

BACKGROUND

Periodontal diseases, including gingivitis and periodontitis, are among the most prevalent oral health issues globally. They compromise the supportive structures of teeth and are influenced by both local and systemic factors. This study aimed to systematically assess the impact of systemic conditions on periodontal health in Malaysian population, addressing the gap in understanding these factors as potential risk factors.

METHODS

A retrospective, non-interventional study was conducted using medical records from Hospital Universiti Sains Malaysia, Kelantan, from September 2019 to December 2022. The study included patients with periodontitis and systemic conditions. Data were analyzed using descriptive statistics, chi-squared tests, Fisher's exact tests, Mann-Whitney U tests, Kruskal-Wallis tests, Spearman's correlation, and logistic regression.

RESULTS

Out of 600 records, 274 patients were included. The cohort was 51.8% male, with a median age of 51 years. Malays accounted for 92.3% of the sample. Hypertension and diabetes mellitus were the most common comorbid conditions. Severe periodontitis was significantly associated with age (45-64 years, p = 0.018) and Malay ethnicity (p = 0.011). Logistic regression revealed that age and ethnicity were significant predictors of periodontitis severity, with Malays being 12.5 times more likely to develop severe periodontitis.

CONCLUSION

Systemic conditions significantly influence periodontitis development and progression. Age and ethnicity are crucial predictors of periodontitis severity in the Malaysian population. Comprehensive risk assessment tools are necessary to incorporate a broader spectrum of risk factors for better management and prevention.

Application of periodontal tissue regeneration combined with orthodontics in oral prosthodontics and its influence and significance on the expressions of IL-1β, TNF-α and IL-5 in periodontal tissue

The aim is to investigate the application of periodontal tissue regeneration combined with orthodontics in oral restoration, and explore its effect and significance on the expressions of Interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and interleukin-5 (IL-5) in periodontal tissue. The patients in observation group were treated with orthodontics combined with periodontal tissue regeneration, and the control group was treated with periodontal tissue regeneration. The total effective rate, adverse reactions, recurrence rate and treatment satisfaction were compared. The masticatory function, language function, aesthetic level, VAS score, quality of life, gingival index (GI), plaque index (PLI), periodontal pocket probing depth (PD), sulcus bleeding index (SBI), IL-1β, TNF-α and IL-5 levels were compared. The recurrence rate of observation group was lower than control group, while the treatment satisfaction was higher after treatment. After treatment, the scores of masticatory, language, aesthetics, physiological, social, emotional, cognitive, and emotional functions and overall health score were higher than before treatment. After treatment, the scores of masticatory and language functions, aesthetics and quality of life of observation group were significantly higher than control group. After treatment, the VAS score, GI, PLI, SBI, PD, IL-1β, TNF-α and IL-5 levels were lower than before. The VAS score, GI, PLI, SBI, PD levels, IL-1β, TNF-α and IL-5 levels of observation group were lower after treatment. Orthodontics combined with periodontal tissue regeneration can help improve the periodontal condition of patients with periodontitis, reduce inflammatory response, improve the level of efficacy and overall safety, and further improve patients' quality of life and treatment satisfaction.

Relationship between serum uric acid levels and periodontitis-A cross-sectional study

OBJECTIVES

Whether there is an association between serum uric acid level (sUA) and periodontitis remains unclear. The aim of this study was to investigate the association between moderate/severe periodontitis and sUA in US adults.

MATERIALS AND METHODS

A total of 3398 participants were included in the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2014. The independent variable was sUA and the dependent variable was periodontitis. SUA for continuous variables, periodontitis as classification variables. Covariate including social demographic variables, life style, systemic diseases, etc. Multiple linear regression models were used to investigate the distribution of differences in covariates between different independent groups. To investigate the association between serum uric acid levels and moderate/severe periodontitis, three models were used (Model 1: unadjusted model; Model 2: adjusted for age, sex, and race/ethnicity; Model 3: adjusted for age, sex, race/ethnicity, education, household income/poverty ratio, smoking behavior, alcohol consumption, dental floss frequency, obesity, hypertension, diabetes, high cholesterol, hyperlipidemia, and sleep disorders).

RESULTS

Among the 3398 patients, 42.5% had moderate/severe periodontitis. Multivariate logistic regression analysis showed that sUA was significantly associated with moderate/severe periodontitis (OR = 1.10, 95%CI: (1.03, 1.16), P = 0.0020) after adjusting for potential confounding factors. In addition, it may vary by race/ethnicity and gender. The association between sUA levels and the prevalence ofperiodontitis was U-shaped in women and non-Hispanic blacks.

CONCLUSION

sUA level is associated with moderate to severe periodontitis. However, the association between sUA levels and the occurrence of periodontitis in women and non-Hispanic blacks followed a U-shaped curve.

CLINICAL RELEVANCE

sUA may directly or indirectly contribute to the global burden of periodontal disease, but there is little evidence that sUA is directly related to periodontitis.This study further supports that high uric acid levels are closely related to periodontitis and may contribute to the control of periodontitis. It also provides new insights into whether it can be used as an indicator to assess the risk or progression of periodontitis. More studies are needed to confirm the relationship between sUA and periodontitis.

Ethical Challenges in Oral Healthcare Services Provided by Non-Governmental Organizations for Refugees in Germany

Oral healthcare is attracting much attention after decades of neglect from policymakers. Recent studies have shown a strong association between oral and overall health, which can lead to serious health problems. Availability of oral healthcare services is an essential part of ensuring universal healthcare coverage. More importantly, current gaps in its accessibility by minority or marginalized population groups are crucial public health as well as ethical concerns. One notable effort to address this issue comes from Non-Governmental Organizations (NGOs), which offer oral healthcare services for non-insured refugees. However, the challenge remains that these care services are not comprehensive, which has implications for the refugees' oral and general health. In this article, we discuss this complex issue in the German healthcare context by including ethical reflections. Therefore, the purpose of this article is to discuss the ethical challenges related to oral healthcare services provided by NGOs for refugees in Germany. First, we will introduce the general oral healthcare context worldwide and in Germany. Second, we will provide a general description of the oral healthcare services provided by NGOs for refugees in Germany, as well as an overview of existing gaps. This will provide us with the context for our third and most important task-discussing the ethical implications of the gaps. In doing so, and since the ethical implications can be several, we demarcate the scope of our analysis by focusing on the specific ethical issues of justice, harm, and autonomy. Finally, we offer some recommendations for how to move forward.

Expression of IL-33 in subjects with periodontitis: a systematic review and meta-analysis

BACKGROUND

Activation of the IL-33/ST2 axis leads to the production of proinflammatory cytokines and thus to the triggering of osteoclastogenesis, which is why it plays an important role in the immunopathogenesis of periodontitis. The aim of this study was to compare IL-33 levels in serum, plasma, saliva and gingival crevicular fluid (GCF) of subjects with chronic periodontitis (CP) in comparison with the control group (CG).

METHODS

This systematic review and meta-analysis followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) and was registered in the Open Science Framework (OSF): https://doi.org/10.17605/OSF.IO/YHUWA . Six electronic databases were used for study identification; PubMed, Google Scholar, ScienceDirect, Web of Science, Scopus and Dentistry & Oral Sciences Source from March 10, 2012 to April 30, 2024. The Joanna Briggs Institute (JBI) tool was used to assess the quality of the included cross-sectional articles and clinical trials.

RESULTS

Of the 949 articles identified, 14 were included according to the inclusion and exclusion criteria. The total number of individuals studied in the included investigations was 814 of whom 445 had CP and 369 were healthy. The reported age range was from 20 to 50 years, with a mean age ± standard deviation of 40.29 ± 7.83 years. Four hundred and twenty-six (52%) patients were men and 388 (48%) were women. Meta-analysis revealed that there is an increase in IL-33 levels in plasma, saliva and GCF of subjects with CP compared to CG (p = * < 0.05).

CONCLUSIONS

This study found a significant increase in IL-33 levels in different biological samples (plasma, saliva and GCF) of individuals with CP compared to CG, thus IL-33 has potential to be a biomarker in the diagnosis of periodontitis.

Toll-like receptor 4 deficiency affects the balance of osteoclastogenesis and osteoblastogenesis in periodontitis

Toll-like receptor 4 (TLR4) acts as a double-edged sword in the occurrence and development of periodontitis. While the activation of TLR4 in macrophages aids in clearing local pathogens, it can also disrupt innate immune responses, upsetting microecological balance and accelerating the destruction of periodontal bone tissues. To date, the effects of TLR4 on osteogenesis and osteoclastogenesis in periodontitis have not been comprehensively studied. In this study, we investigated the development of periodontitis in the Tlr4-/- mice by ligating their second molars with silk threads. Compared to wild-type (WT) mice, Tlr4-/- mice demonstrated increased resistance to periodontitis-associated bone destruction, as evidenced by decreased bone resorption and enhanced bone regeneration. Mechanistically, the deletion of Tlr4 not only inhibited osteoclast formation by reducing the expression of NFATc1, CTSK and TRAP, but also enhanced osteogenic abilities through increased expression of OCN, OPN and RUNX2. In conclusion, TLR4 tips the balance of osteoclastogenesis and osteogenesis, thereby promoting periodontal bone destruction in periodontitis.

A yeast-malic acid crosslinker/polyacrylic acid hydrogel containing doxycycline for the treatment of periodontitis

Doxycycline (DX) is a drug of choice for the treatment of periodontitis, with the limitation of requiring a high dose, which may be overcome by the preparation of a targeted controlled-release hydrogel containing a newly synthesized yeast-malic acid crosslinker (YMC). YMC was synthesized via thermochemical modification of yeast with malic acid at 100-140 °C and compared with glutaraldehyde-saturated toluene (GST). Swelling capacity, acid and carboxyl content, scanning electron microscopy (SEM) imaging, Brunauer-Emmett-Teller (BET) analysis, viscosity, cross-linking density, DX loading and release behavior at pH 6.5, mucoadhesion, and antimicrobial and periodontal efficacy of the glutaraldehyde hydrogel (HGG) and YMC hydrogel (HGY) were compared. Changes from C-O (1421 cm-1) to C[double bond, length as m-dash]OOR (1702 cm-1) in the infrared spectroscopy, along with changes in the degree of substitution from 0 to 0.39, degree of esterification from 0 to 40 ± 1.5 and COOH content from 129 ± 0.5 to 290 ± 0.5 (meq. per 100 g), were found between yeast to YMC, respectively. The results revealed 1.5 times more dynamic swelling, 0.25-fold decrease in acid content, 2.3-fold increase in carboxyl content, and 1.2- and 2.1-fold increases in cross-linking density and viscosity of HGY as compared to HGG, respectively. The SEM and BET results revealed that HGY had a 2 times greater porous surface than HGG. HGY/DX was 35 ± 2% more effective in controlling periodontitis bacteria, decreased periodontal depth from 4 to 3.2 mm, and gingival index from 3 to 1 as compared to HGG/DX in patients suffering from periodontitis. HGY/DX not only serves as a tool for the controlled release of DX in periodontal pockets but also contributes to the treatment of gingival periodontitis.

Exosomes miR-92a-3p from human exfoliated deciduous teeth inhibits periodontitis progression via the KLF4/PI3K/AKT pathway

BACKGROUND

Periodontitis is a chronic inflammatory disease mediated by dysbiosis of the oral microflora, resulting in the destruction of periodontal tissue. Increasing evidence suggested that mesenchymal stem cell (MSCs) and exosomes derived from MSCs play a critical role in periodontal tissue regeneration. However, whether stem cells from exfoliated deciduous teeth (SHED)-secreted exosomes can improve the therapeutic potential of periodontitis is largely unknown.

OBJECTIVE

Here, we aim to evaluate the effect of SHED-exosomes on inflammation, apoptosis and osteogenic differentiation in periodontitis.

METHODS

The periodontitis cell model was constructed by stimulating periodontal ligament stem cells (PDLSCs) with lipopolysaccharide (LPS), and the periodontitis rats were established by ligation.

RESULTS

First, we isolated exosomes from the SHED, and we figured out that exosomes secreted by SHED were enriched in miR-92a-3p and the exosomes enhanced proliferation and osteogenic differentiation and reduced apoptosis and inflammatory responses in PDLSCs. In addition, we found that SHED-exosomes alleviated inflammatory effect and elevated the expression of osteogenic-related genes in periodontitis rat model. Moreover, miR-92a-3p targeted downstream Krüppel-Like Transcription Factor 4 (KLF4) and regulated the PI3K/AKT pathway. Finally, our data indicated that upregulation of KLF4 or activation of PI3K/AKT by 740Y-P counteracted the inhibitory effect of SHED-exosomes on periodontitis progression.

CONCLUSION

Taken together, our finding revealed that exosomal miR-92a-3p derived from SHED contributed to the alleviation of periodontitis development and progression through inactivating the KLF4/PI3K/AKT signaling pathway, which may provide a potential target for the treatment of periodontitis.

ATF3 affects osteogenic differentiation in inflammatory hPDLSCs by mediating ferroptosis via regulating the Nrf2/HO-1 signaling pathway

Activating transcription factor 3 (ATF3) has been identified as a regulator associated with osteoblast differentiation. However, the effects of ATF3 on the osteogenic differentiation and proliferation of human periodontal stem cells (hPDLSCs) in periodontitis have not been reported. With the purpose of establishing an in vitro model of periodontitis, hPDLSCs were challenged with lipopolysaccharide (LPS). The Cell Counting Kit-8 assay was applied to assess cell viability, while reverse transcription-quantitative PCR and western blotting were employed to detect ATF3 expression. Inflammatory release was assessed using ELISA, together with western blotting. Lipid peroxidation was explored using the C11 BODIPY 581/591 probe, biochemical kits, thiobarbituric acid reactive substances (TBARS) assay and DCFH-DA staining. Iron and Fe2+ levels, and the expression levels of ferroptosis-related proteins were measured using corresponding kits and western blotting. Osteogenic differentiative capability was evaluated using alkaline phosphatase staining, Alizarin red staining and western blotting. The expression levels of proteins associated with Nrf2/HO-1 signaling were identified using western blotting. The results indicated that ATF3 expression was upregulated in LPS-induced hPDLSCs. The knockdown of ATF3 alleviated the LPS-induced inflammatory response in hPDLSCs, together with increased levels of TNF-α, IL-6, IL-1β, Cox-2 and iNOS, and decreased levels of IL-10. ATF3 silencing also led to lower TBARS production rate, and reduced levels of reactive oxygen species, iron, Fe2+, ACSL4 and TFR1, whereas it elevated the levels of SLC7A11 and GPX4. In addition, ATF3 silencing promoted hPDLSC mineralization and cell differentiation, and elevated the levels of OCN2, RUNX2 and BMP2. Additionally, ATF3 depletion upregulated the expression levels of proteins related with Nrf2/HO-1 signaling. The Nrf2 inhibitor ML385 partially counteracted the effects of ATF3 interference on the LPS-challenged inflammatory response, lipid peroxidation, ferroptosis as well as osteogenic differentiative capability in hPDLSCs. In summary, the results revealed that ATF3 silencing suppressed inflammation and ferroptosis, while it improved osteogenic differentiation in LPS-induced hPDLSCs by regulating Nrf2/HO-1 signaling, which may provide promising therapeutic targets for the treatment of periodontitis.

The bidirectional effect of neutrophils on periodontitis model in mice: A systematic review

OBJECTIVE

To evaluate the regulatory role of neutrophils as the first line of host immune defense in the periodontal microenvironment of mice.

METHODS

A systematic search was performed using PubMed, Web of Science, and ScienceDirect databases for articles published between 2012 and 2023. In this review, articles investigating the effect of neutrophils on alveolar bone resorption in a mouse model of periodontitis were selected and evaluated according to eligibility criteria. Important variables that may influence outcomes were analyzed.

RESULTS

Eleven articles were included in this systematic review. The results showed that because of their immune defense functions, the functional homeostasis of local neutrophils is critical for periodontal health. Neutrophil deficiency aggravates alveolar bone loss. However, several studies have shown that excessive neutrophil infiltration is positively correlated with alveolar bone resorption caused by periodontitis in mice. Therefore, the homeostasis of neutrophil function needs to be considered in the treatment of periodontitis.

CONCLUSIONS

Pooled analysis suggests that neutrophils play a bidirectional role in periodontal tissue remodeling in mouse periodontitis models. Therefore, targeted regulation of local neutrophil function provides a novel strategy for the treatment of periodontitis.

Bidirectional Association between Periodontitis and Thyroid Disease: A Scoping Review

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

The effect of virtual simulation technology applied to undergraduate teaching of periodontal probing

INTRODUCTION

The rise of virtual simulation technology and dental simulators has created a new pedagogical approach for undergraduate medical education. The purpose of this study is to evaluate the effect of virtual simulation (VS) technology on improving the students' comprehensive abilities in periodontal probing teaching in pre-practicum periodontology, such as increasing the accuracy of probing, tactile perception and performance on force control.

MATERIALS AND METHODS

Twenty students were randomly selected among the fourth-year students and equally divided into VS technology teaching group (VS group) and traditional teaching group (TT group) by drawing half lots. One day later, students were required to probe the periodontal pathology model. The consistency rate between PD measurements and PD reference values, time consumption and final exam scores were recorded and statistically analysed using an unpaired Student's t test and p < .05 was considered statistical significance. Finally, questionnaires relating to teaching methods evaluation and the fidelity of the digital VS training system were distributed to students and teachers.

RESULTS

VS group had a significantly higher consistency rate (72.976 ± 6.811%) than TT group (64.107 ± 4.988%, p = .004). To specify, the difference of consistency rates between the two groups in posterior teeth was larger than anterior teeth. Similarly, a larger difference was also found in proximal surfaces compared with buccal-lingual surfaces. As the pocket depth increased, the difference between the two groups increased too. These results indicated that VS is more efficient in complicated parts of periodontal probing teaching. In addition, students in VS group spent less time and gained a higher score than TT group (p < .05). The overall satisfaction rating in VS group was significantly higher than TT group. Lastly, teachers gave significant lower scores than students concerning the fidelity of VS system.

CONCLUSION

Although there are much to improve, VS technology has obvious advantages in periodontal probing teaching in pre-practicum periodontology.

Ibero-Panamerican Federation of Periodontology Delphi study on the trends of periodontology and periodontics by the year 2030. A Latin American consensus

BACKGROUND AND OBJECTIVE

As elsewhere in the world, the prevalence of periodontitis in stages I-II is high in the Latin American population, this scenario emphasizes the need for identification of urgent needs for allocating adequate resources to provide diagnosis, prevention, and treatment of these diseases. The aim of this Delphi study was to predict the trends in periodontology/periodontics in the Latin American region by the year 2030.

METHODS

A steering committee and an advisory group of experts in periodontology/periodontics were selected from 16 countries. An open questionnaire of 60 questions was validated and used following the Delphi methodology.

RESULTS

Two hundred and twenty-five experts from Latin America answered the two rounds of the questionnaire. Moderate to strong consensus was reached on 45 questions (75%). The prediction was that the prevalence of gingivitis and periodontitis in stages I and II will be maintained, the importance of the link with systemic diseases will increase, and the impact of prevention and periodontal treatment will also increase, mainly in the private sector. There was a strong consensus that plastic and regenerative surgical procedures will increase, as well as the demand for training in the specialty of periodontology.

CONCLUSIONS

The present study has provided relevant and useful information on predictions in periodontology/periodontics in Latin America, with important level of consensus among experts. It has been predicted that periodontitis will still be a highly prevalent disease, and its links with other medical conditions should demand more attention by health authorities to develop adequate prevention and management policies and strategies.

Analysis of subgingival microbiota and IL-1β, TNF-α and CX3CL1 levels in gingival crevicular fluid of fixed dental prostheses

Prosthetic biomaterials can affect the composition of the subgingival microbiota and consequently the production of proinflammatory cytokines, causing damage to the periodontium. A total of 40 patients were divided into two groups: 20 with monolithic zirconia (MZ) prostheses and 20 with porcelain fused to metal (PFM) with nickel-chromium (Ni-Cr) alloy prostheses. Subgingival plaque and gingival crevicular fluid samples were taken. The Checkerboard technique for DNA-DNA hybridization and the enzyme-linked immunosorbent assay technique were performed. Teeth with MZ presented a lower percentage of bleeding on probing and tooth mobility compared to teeth with PFM with Ni-Cr alloy. Prosthodontic teeth harbored higher total levels of the 18 bacterial species than non-prosthodontic teeth. There was a higher prevalence of S. gordonii and V. parvula species in PFM with Ni-Cr alloy compared to MZ. There was an increase in IL-1β, TNF-α and CX3CL1 levels in PFM with Ni-Cr alloy compared to MZ. MZ is a candidate biomaterial with fewer negative effects on the periodontium, allowing for longer prostheses longevity in the mouth.

Expression of TNF-α, omentin-1, and IL-6 before and after adjunctive treatment with a bioactive antimicrobial peptide periodontal gel

BACKGROUND

The objective of this study was to evaluate and compare the expression levels of TNF-α, omentin-1, and IL-6 in periodontitis patients before and after treatment with biological antimicrobial peptide (AMP) periodontal gel.

METHODS

There involved 86 periodontitis patients admitted to our hospital from January 2020 to March 2021. They were equally and randomly distributed into the study group and the control group. The efficacy and adverse reactions were compared between the two groups after treatment, Additionally, the sulcus bleeding index (SBI), plaque index (PLI), gingival index (GI), periodontal probing depth (PD), and levels of TNF-α, omentin-1, and IL-6 were measured before and after treatment.

RESULTS

After treatment, the total effective rate of the study group was significantly higher than that of the control group (p < 0.05), while the scores of four indicators (SBI, PLI, GI, and PD) and the levels of TNF-α, omentin-1, and IL-6 in the study group were evidently lower than the control group (p < 0.05). The study group had 1 case of mild irritant reaction, with an adverse reaction rate of 2.33% (1/43). And the control group had 1 case of nausea and 1 case of allergy, with an adverse reaction rate of 4.65% (2/43). The adverse reactions demonstrated no statistical difference between the two groups (χ2  = 0.345, p = 0.557).

CONCLUSIONS

The levels of TNF-α and IL-6 were highly expressed before the auxiliary therapy of biological AMP periodontal gel for periodontitis, alongside low expression of omentin-1. Subsequently, the biological antibacterial polypeptide periodontal gel demonstrated efficacy in the treatment of periodontitis.

MicroRNAs: The Missing Link between Hypertension and Periodontitis?

Cardiovascular diseases are the leading cause of death worldwide, and arterial hypertension is a recognized cardiovascular risk factor that is responsible for high morbidity and mortality. Arterial hypertension is the result of an inflammatory process that results in the remodeling and thickening of the vascular walls, which is associated with an immunological response. Previous studies have attempted to demonstrate the relationship between oral disease, inflammation, and the development of systemic diseases. Currently, the existence of an association between periodontitis and hypertension is a controversial issue because the underlying pathophysiological processes and inflammatory mechanisms common to both diseases are unknown. This is due to the fact that periodontitis is a chronic inflammatory disease that affects the interface of teeth and surrounding tissues. However, the most likely explanation for understanding this association is related to low-grade chronic inflammation. An initial path in the study of the relationship between the mentioned pathologies is the possibility of an epigenetic influence, mediated by noncoding RNAs as microRNAs. Thus, in the present review we describe the role of microRNAs related to arterial hypertension and/or periodontitis. In addition, we identified 13 common microRNAs between periodontitis and hypertension. According to the predictions of the DIANA-mirPath program, they can regulate genes involved in 52 signaling pathways.

Generalised Periodontitis: Examining TAS2R16 Serum Levels and Common Gene Polymorphisms (rs860170, rs978739, rs1357949)

The objective of this study was to evaluate and compare the associations between TAS2R16 serum levels and common gene rs860170, rs978739, and rs1357949 polymorphisms in patients affected by generalized periodontitis. The study enrolled 590 patients: 280 patients with periodontitis and 310 healthy controls as a reference group. Patients underwent periodontal examination and radiographic analysis to confirm the periodontitis diagnosis. Blood samples were collected, and the DNA salting-out method was used for DNA extraction from peripheral venous blood. Genotyping of TAS2R16 (rs860170, rs978739, and rs1357949) was performed using real-time polymerase chain reaction (RT-PCR), and serum level analysis was performed for both periodontitis-affected patients and reference group subjects. The analysis of TAS2R16 rs860170 (TT, CT, and CC) showed a statistically significant difference between generalized periodontitis and the reference group (41.8%, 58.2%, and 0% vs. 38.7%, 56.1%, and 5.2%, p < 0.001). TAS2R16 rs860170 (TT, CT, and CC) showed a statistically significant difference between males in generalized periodontitis and reference groups (38.4%, 61.6%, and 0% vs. 32.9%, 56.6%, and 10.5%, p = 0.002). Female-specific analysis showed that the TAS2R16 rs978739 C allele was more frequent in generalized periodontitis compared to the reference group (37.5% vs. 28.7%, p = 0.016). Subjects aged 70 years and older demonstrated a statistically significant difference in TAS2R16 rs860170 (TT, CT, and CC) between generalized periodontitis and the reference group (42.8%, 57.2%, and 0% vs. 38.6%, 53.8%, and 7.6%, p = 0.003). TAS2R16 serum levels were elevated in generalized periodontitis compared to the reference group (0.112 (0.06) ng/mL vs. 0.075 (0.03) ng/mL, p = 0.002). Females carrying the TAS2R16 rs978739 C allele were more prone to generalized periodontitis development. Associations were found between TAS2R16 rs860170 polymorphisms, elevated TAS2R16 serum levels, and generalized periodontitis development.

Herpesviruses and SARS-CoV-2: Viral Association with Oral Inflammatory Diseases

The oral cavity is a niche for diverse microbes, including viruses. Members of the Herpesviridae family, comprised of dsDNA viruses, as well as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an ssRNA virus, are among the most prevalent viruses infecting the oral cavity, and they exhibit clinical manifestations unique to oral tissues. Viral infection of oral mucosal epithelia triggers an immune response that results in prolonged inflammation. The clinical and systemic disease manifestations of HHV have been researched extensively, and several recent studies have illuminated the relationship between HHV and oral inflammatory diseases. Burgeoning evidence suggests the oral manifestation of SARS-CoV-2 infection includes xerostomia, dysgeusia, periodontal disease, mucositis, and opportunistic viral and bacterial infections, collectively described as oral post-acute sequelae of COVID-19 (PASC). These diverse sequelae could be a result of intensified immune responses initially due to the copious production of proinflammatory cytokines: the so-called "cytokine storm syndrome", facilitating widespread oral and non-oral tissue damage. This review explores the interplay between HHV, SARS-CoV-2, and oral inflammatory diseases such as periodontitis, endodontic disease, and peri-implantitis. Additionally, the review discusses proper diagnostic techniques for identifying viral infection and how viral diagnostics can lead to improved overall patient health.

Association between life's essential 8 and periodontitis: a population-based study

BACKGROUND

The American Heart Association has developed a novel cardiovascular health indicator called Life's Essential 8 (LE8). However, no one has reported using LE8 to assess periodontitis. This study aimed to investigate the association between LE8 and periodontitis in American adults.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2014 were used for this investigation. LE8 was the independent variable, and it is divided into three grades: high, moderate, and low. Periodontitis was the dependent variable, and the classification of periodontitis was based on the criteria of Eke in 2012. Multivariable logistic regression models were used to explore the relationship between LE8 and periodontitis.

RESULTS

A total of 9,039 participants with an average age of 52.16 ± 14.21 years were enrolled in this study, of whom 48.29% were male and 51.71% were female. The mean and standard deviation of LE8 was 66.29 ± 14.57, and the prevalence of periodontitis was 50.48% overall. The LE8 score and periodontitis in the fully adjusted logistic regression model showed a negative correlation (OR = 0.98; 95% CI, 0.98-0.99, p < 0.001). This result persisted when Life's Essential 8 was categorized into low, moderate, and high groups. Compared with those in the lowest group, those in the highest LE8 group had a 47% decreased risk of periodontitis (OR = 0.53; 95% CI, 0.46-0.66, P < 0.001).

CONCLUSIONS

This cross-sectional investigation revealed a negative relationship between the LE8 score and the likelihood of periodontitis.

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.

Periodontal disease and risk of atrial fibrillation or atrial flutter: A systematic review and meta-analysis

Background

We conducted a study to evaluate the risk of atrial fibrillation (AF) and atrial flutter (AFL) in periodontal disease (PD) patients.

Methods

Cohort studies that evaluate the risk of AF or AFL in PD patients were included. The risk was expressed in the pooled odd ratio (OR) with 95% confidence interval (CI).

Results

A total of four cohort studies were included. We found that patients with PD have a significantly higher risk of AF/AFL compared to those without PD with the pooled OR of 1.33 (95% CI 1.29-1.38; p = 0.357, I 2 = 3.0%).

Conclusions

PD increases the risk of AF and AFL.

Molecular mechanism of curcumin on periodontitis: A pharmacological network study

OBJECTIVE

This study aimed to identify the molecular mechanism of curcumin on periodontitis based on a pharmacological network strategy.

METHODS

The potential therapeutic targets of curcumin and differentially expressed genes in periodontitis were identified. Subsequently, we extracted the molecules in common and analyzed them. A metabolic pathway enrichment and gene ontology analysis were performed and the protein-protein interaction network was inferred. These analyses allowed the identification of key proteins. Finally, a molecular docking of the main key proteins was performed with curcumin.

RESULTS

Our results showed that 55 genes are differentially expressed in periodontitis and are potential targets of curcumin. In addition, we observed that these genes participate in cell motility and immune response and are related to chemokine receptors (CXCRs) and enzymatic activity, such as arachidonate 5-lipoxygenase (ALOX5). We identified six key proteins, IL1B, CXCL8, CD44, MMP2, EGFR, and ITGAM; molecular docking revealed that these six proteins spontaneously bind to curcumin.

CONCLUSION

The results of this study helps us understand the molecular mechanism of curcumin in periodontitis. We propose that curcumin affects proinflammatory cytokines, ALOX5, and cell migration through chemokine receptors and acts on the cell membrane. Additionally, we identified six key proteins that are essential in this mechanism, all of which spontaneously bind to curcumin.

Knockdown of TRPM2 promotes osteogenic differentiation of human periodontal ligament stem cells by modulating NF-κB /NLRP3 pathway

Periodontitis is characterized by periodontal destruction triggered by chronic inflammation. The optimal treatment for periodontitis is to improve the periodontal microenvironment, reduce inflammation and achieve periodontal regeneration. Recently, the role of TRPM2 in inflammatory diseases has been reported. However, the function of TRPM2 in periodontal disease and the biological mechanism remain elusive. Therefore, this study aimed to identify the role and explore the underlying mechanisms of TRPM2 in periodontal disease. Here, we first identified the characterization of human periodontal ligament stem cells (PDLSCs). Oil Red O Staining and Alizarin Red mineralized matrix were used to evaluate the multi-differentiation capacity of cells. Flow cytometry was employed to detect MSC-specific surface markers of hPDLSCs. hPDLSCs were treated with 0, 5, 10 or 40 μg/mL of TNF-α for 72 h. Western blot assay were performed to examine the expression of Transient receptor potential cation channel, subfamily M, member 2 (TRPM2) in hPDLSCs. CCK8 and colony formation assays were used to detect the cell viability and proliferation of hPDLSCs, which revealed that TRPM2 knockdown promoted hPDLSCs proliferation. Then, ALP activity in hPDLSCs was detected by ALP activity detection kit. Next, the expression of ALP and Runx2 in hPDLSCs was detected by immunofluorescence staining. The result showed that TRPM2 knockdown promoted osteogenic differentiation and affected the genes expression of osteogenic. Finally, the expressions of p-p65, p65, p-IκBα, IκBα and NLRP3 in hPDLSCs were detected by western blot assay. Together, these results suggested that knockdown of TRPM2 accelerated osteogenic differentiation of hPDLSCs through mediating NF-κB /NLRP3 pathway.

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.

Association between periodontitis and postoperative complications in hospital medical surgical procedures: a systematic review

Background

Periodontitis is potentially harmful in the perioperative period due to biofilm generating a environment for bacteria to spread and colonize other anatomical areas, which can generate a potential risk of infection, delayed healing, increased morbidity, and even induce avulsion in intubated patients, and subsequent aspiration or ingestion of teeth with increased mobility.

Objective

Associate the presence of periodontitis and postoperative complications in patients who underwent an in-hospital medical surgical procedure.

Methods

A systematic review based on studies extracted from PubMed and Scopus was carried out on June 10, 2020, based on the Population, Intervention, Comparison and Result search strategy. As inclusion criteria, the studies had to include all the disaggregated terms of the research question, have a publication date of less than 15 years, and the target population had to have undergone elective hospital medical-surgical interventions. The exclusion criteria corresponded to not presenting an analytical or experimental observational study design, not having made a periodontal clinical diagnosis of the study subjects, and not expressing in the results the presence of postoperative medical-hospital complications. Articles were assessed for quality by supplementing the STROBE guideline and Newcastle Ottawa, for risk of bias by supplementing the STROBE guideline and the Cochrane Collaboration handbook tool.

Results

A total of 131 articles were obtained, which were subjected to a selection process, resulting in 5 final analytical observational studies. A meta-analysis was performed and determined that periodontitis was a risk factor to postoperative complications after surgical procedures with an OR = 4,76; 95%CI [1,11-20,41].

Conclusions

Optimize the guidelines for assessing quality and risk of bias can make their comparison with other studies complex, however it was determined in a statistically significant way that patients with periodontitis have a higher risk of generating postoperative complications after a medical hospital surgery.

The increasing importance of the oral microbiome in periodontal health and disease

Herein, the aim is to discuss the current knowledge of microbiome and periodontal diseases. Current treatment strategies include mechanical therapy such as root planing, scaling, deep pocket debridement and antimicrobial chemotherapy as an adjuvant therapy. Among promising therapeutic strategies, dental probiotics and oral microbiome transplantation have gained attention, and may be used to treat bacterial imbalances by competing with pathogenic bacteria for nutrients and adhesion surfaces, as well as probiotics targeting the gut microbiome. Development of strategies to prevent and treat periodontal diseases are warranted as both are highly prevalent and can affect human health. Further studies are necessary to better comprehend the microbiome in order to develop innovative preventative measures as well as efficacious therapies against periodontal diseases.

Antimicrobial efficacy of chlorine agents against selected oral pathogens

OBJECTIVES

Method-dependent comparison of antimicrobial agents' efficacy against oral pathogens.

MATERIALS AND METHODS

Several sodium hypochlorite solutions (NaOCl)-Perisolv®, Carisolv® and Dakin's solution-were equated with chlorhexidine (CHX) and hydrogen peroxide (H2O2) against ten oral micro-organisms related to caries and periodontitis using different minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) techniques. Agents were adjusted to the final 70 mmol/L concentration of active chlorine molecule.

RESULTS

Apart from H2O2 and the amino acids of Perisolv®, all the agents revealed an antimicrobial effect. Agar diffusion test ranked CHX (p < 0.05) as the most effective against all ten specimens, followed by the NaOCl of Perisolv® and Dakin's solution. Correspondingly, in broth microdilution on agar, CHX was the most effective in eradicating micro-organisms at 0.03 mmol/L compared with 2.2 mmol/L of Dakin's solution. In contrast, the bactericidal concentration of Dakin's solution was the most effective at 0.2 mmol/L, (p < 0.001), followed by Perisolv® (2.14 mmol/L), CHX (2.38 mmol/L) and Carisolv® (3.33 mmol/L) after 5 and 10 min in broth dilution test. In live/dead analysis, 60-min exposure to a 2-fold concentration of agents resulted in two-log Aggregatibacter actinomycetemcomitans inhibition by CHX (35 mmol/L) whilst Streptococcus mutans was more susceptible, in 0.8 and 8.8 mmol/L, after 10 min to CHX and Dakin's respectively.

CONCLUSION

Replacement of CHX with tested hypochlorite agents showed evident potential and promoted rapid antimicrobial effect.

CLINICAL RELEVANCE

Effective antimicrobial agents are crucial in controlling pathogen-induced oral infections increasing clinical possibilities to combat oral biofilms. Additionally, CHX substitution with hypochlorite agents could eliminate CHX's adverse effects.

Periodontal and cardiovascular therapies modify specialized pro-resolving lipid mediator (sPRLM) (LPXA4, PD1, RvE1, RvD1, and MaR1)-mediated pathway: the first pilot clinical study

OBJECTIVES

Cardiovascular disease (CVD) and periodontal disease have a common pathogenesis with inflammation and resolution steps. Although the relationships among periodontal disease, CVD, and specialized pro-resolving lipid mediator (sPRLM)s are well known, there is no study about the combined effects of cardiovascular and periodontal treatments on sPRLM levels. It was aimed to evaluate the effects of periodontal and cardiovascular therapies on sPRLMs (lipoxin A4, protectin (PD)1, resolvin (Rv) E1, RvD1, and maresin (MaR)1) in patients with CVD and periodontal disease.

METHODS

This observational study consisted of fifty-five patients with CVD and mild or moderate periodontitis. The clinical periodontal parameters (plaque index, gingival index, probing pocket depth, percentage of bleeding on probing, and clinical attachment level) and blood and unstimulated total saliva samples were obtained at baseline, at 3 months (following only cardiovascular therapy), and at 6 months (following cardiovascular and periodontal therapies). The blood count and serum levels of cardiometabolic biomarkers (white blood cell, neutrophil/lymphocyte, serum total cholesterol (TC), triglyceride, and low and high-density lipoprotein (HDL) levels) were evaluated. sPRLMs were evaluated by ELISA.

RESULTS

There were significant decreases in body mass index, clinical periodontal parameters, WBC, LDL, PD1, and RvD1 at 6 months compared to baseline. The decreases in TC/HDL, RvE1, and MaR1 levels were significant at 3 and 6 months compared to baseline (p < 0.05).

CONCLUSION(S)

The combination of cardiovascular and periodontal treatments leads to significant reductions in clinical periodontal and cardiometabolic parameters and sPRLMs.

CLINICAL RELEVANCE

Our report, which is the first in their field, suggested that cardiovascular and periodontal therapies provide an important contribution via decreasing the periodontal and atherosclerotic inflammation modulating sPRLMs. This finding will be a big step toward increasing the quality of life in these patients by drawing attention to importance of public health associated with oral hygiene, periodontal health, and systemic phase of periodontal treatment.

Antibacterial Activity of a Bioactive Tooth-Coating Material Containing Surface Pre-Reacted Glass in a Complex Multispecies Subgingival Biofilm

Bioactive materials were developed with the ability to release fluoride and provide some antimicrobial potential, to be widely used in dentistry today. However, few scientific studies have evaluated the antimicrobial activity of bioactive surface pre-reacted glass (S-PRG) coatings (PRG Barrier Coat, Shofu, Kyoto, Japan) on periodontopathogenic biofilms. This study evaluated the antibacterial activity of S-PRG fillers on the microbial profile of multispecies subgingival biofilms. A Calgary Biofilm Device (CBD) was used to grow a 33-species biofilm related to periodontitis for 7 days. The S-PRG coating was applied on CBD pins from the test group and photo-activated (PRG Barrier Coat, Shofu), while the control group received no coating. Seven days after treatment, the total bacterial counts, metabolic activity, and microbial profile of the biofilms were observed using a colorimetric assay and DNA-DNA hybridization. Statistical analyses were applied; namely, the Mann-Whitney, Kruskal-Wallis, and Dunn's post hoc tests. The bacterial activity of the test group was reduced by 25.7% compared with that of the control group. A statistically significant reduction was observed for the counts of 15 species: A. naeslundii, A. odontolyticus, V. parvula, C. ochracea, C. sputigena, E. corrodens, C. gracilis, F. nucleatum polymorphum, F. nucleatum vincentii, F. periodonticum, P. intermedia, P. gingivalis, G. morbillorum, S. anginosus, and S. noxia (p ≤ 0.05). The bioactive coating containing S-PRG modified the composition of the subgingival biofilm in vitro, thereby decreasing colonization by pathogens.

PRMT5 inhibition ameliorates inflammation and promotes the osteogenic differentiation of LPS‑induced periodontal stem cells via STAT3/NF‑κB signaling

It has been reported that protein arginine methyltransferase 5 (PRMT5) serves a significant role in osteogenic differentiation and inflammatory response. Nevertheless, its role in periodontitis as well as its underlying mechanism remain to be elucidated. The aim of the present study was to explore the role of PRMT5 in periodontitis and whether PRMT5 could reduce liposaccharide (LPS)-induced inflammation of human periodontal ligament stem cells (hPDLSCs) and promote osteogenic differentiation through STAT3/NF-κB signaling. In the current study, the expression levels of PRMT5 were determined in LPS-induced hPDLSCs by reverse transcription-quantitative PCR and western blot analysis. ELISA and western blot analysis were employed to assess the secretion and expression levels of inflammatory factors, respectively. The osteogenic differentiation and mineralization potential of hPDLSCs were evaluated using alkaline phosphatase (ALP) activity assay, Alizarin red staining and western blot analysis. Additionally, western blot analysis was applied to determine the expression levels of the STAT3/NF-κB signaling pathway-related proteins. The results showed that the expression levels of PRMT5 were significantly enhanced in LPS-induced hPDLSCs. Additionally, PRMT5 knockdown reduced the contents of IL-1β, IL-6, TNF-α, inducible nitric oxide synthase and cyclooxygenase-2. PRMT5 depletion also enhanced ALP activity, improved the mineralization ability and upregulated bone morphogenetic protein 2, osteocalcin and runt-related transcription factor 2 in LPS-induced hPDLSCs. Furthermore, PRMT5 knockdown inhibited inflammation and promoted the osteogenic differentiation of hPDLSCs via blocking the activation of the STAT3/NF-κB signaling pathway. In conclusion, PRMT5 inhibition suppressed LPS-induced inflammation and accelerated osteogenic differentiation in hPDLSCs via regulating STAT3/NF-κB signaling, thus providing a potential targeted therapy for the improvement of periodontitis.

Green Alternatives as Antimicrobial Agents in Mitigating Periodontal Diseases: A Narrative Review

Periodontal diseases and dental caries are the most common infectious oral diseases impacting oral health globally. Oral cavity health is crucial for enhancing life quality since it serves as the entranceway to general health. The oral microbiome and oral infectious diseases are strongly correlated. Gram-negative anaerobic bacteria have been associated with periodontal diseases. Due to the shortcomings of several antimicrobial medications frequently applied in dentistry, the lack of resources in developing countries, the prevalence of oral inflammatory conditions, and the rise in bacterial antibiotic resistance, there is a need for reliable, efficient, and affordable alternative solutions for the prevention and treatment of periodontal diseases. Several accessible chemical agents can alter the oral microbiota, although these substances also have unfavorable symptoms such as vomiting, diarrhea, and tooth discoloration. Natural phytochemicals generated from plants that have historically been used as medicines are categorized as prospective alternatives due to the ongoing quest for substitute products. This review concentrated on phytochemicals or herbal extracts that impact periodontal diseases by decreasing the formation of dental biofilms and plaques, preventing the proliferation of oral pathogens, and inhibiting bacterial adhesion to surfaces. Investigations examining the effectiveness and safety of plant-based medicines have also been presented, including those conducted over the past decade.

Role of ubiquitin-specific protease 5 in the inflammatory response of chronic periodontitis

BACKGROUND

The systemic inflammatory response caused by chronic periodontitis is a risk factor for multiple diseases. Ubiquitin-specific protease 5 (USP5) is a kind of deubiquitinase which mainly responsible for dissociating unanchored polyubiquitin. However, the functions of USP5 in chronic periodontitis have not been reported.

METHODS

Chronic periodontitis patients were recruited, and their periodontal samples were collected. The levels of USP5, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in gingival crevicular fluid were evaluated by ELISA. The expression of USP5, TNF-α, IL-6, and IL-1β in human periodontal ligament stem cells (PDLSCs) was estimated by qRT-PCR assay. The activation of STAT3 signaling was examined by Western blot.

RESULTS

USP5 was upregulated in the gingival crevicular fluid and gingival tissues of chronic periodontitis patients. USP5 expression was positively correlated with the expression of proinflammatory factors. USP5 knockdown and deubiquitinase inhibitor inhibited LPS-induced inflammatory responses in PDLSCs. Suppressing USP5 inhibited STAT3 signaling in PDLSCs.

CONCLUSION

Suppression deubiquitinase USP5 inhibits the inflammatory response of chronic periodontitis by suppressing STAT3 signaling.

Effect of LSD1 on osteogenic differentiation of human periodontal ligament stem cells in periodontitis

OBJECTIVE

Periodontitis is a chronic inflammation of periodontal tissues. This study is expected to assess the effect of LSD1 on the osteogenic differentiation of hPDLSCs in periodontitis.

METHODS

hPDLSCs were separated, cultivated, and identified, and then treated by LPS to induce inflammatory microenvironment and subjected to osteogenic differentiation. Subsequently, LSD1 expression was determined, and then silenced to assess its effect on hPDLSCs. Next, the binding relation between LSD1 and miR-590-3p was analyzed. miR-590-3p expression was detected and then overexpressed to evaluate its role in hPDLSCs in periodontitis. Afterward, the relation between LSD1 and OSX was analyzed. H3K4me2 level and OSX transcription were measured, and the role of H3K4me2 was determined. Additionally, the role of OSX in hPDLSCs was verified.

RESULTS

LSD1 was poorly expressed after osteogenic differentiation of hPDLSCs while it was rescued upon LPS induction. The osteogenic differentiation of hPDLSC in periodontitis was strengthened upon LSD1 downregulation. Besides, miR-590-3p targeted LSD1 transcription, and LSD1 inhibited OSX transcription via H3K4me2 demethylation. miR-590-3p overexpression improved osteogenic differentiation of hPDLSCs in periodontitis. But this improvement was annulled by OSX inhibition.

CONCLUSION

miR-590-3p targeted LSD1 transcription and upregulated H3K4me2 methylation to promote OSX transcription, thereby encouraging osteogenic differentiation of hPDLSCs in periodontitis.

Salivary Flow Rate and Oral Status in Patients with Primary Sjögren's Syndrome and Diffuse Cutaneous Systemic Sclerosis: A Cross-Sectional Study

Determination of salivary flow rate and oral status in patients with primary Sjögren's Syndrome (pSS) and diffuse cutaneous systemic sclerosis (dcSSc) and comparison with control subjects. Thirty-one pSS patients, 28 dcSSc patients, and 28 control subjects participated in this single-center, cross-sectional study. Unstimulated whole salivary flow rate (UWSFR) and stimulated whole salivary flow rate (SWSFR), salivary pH, DMFT index (D-decayed, M-missing, F-filled tooth), periodontal pocket depth (PPD), clinical attachment level (CAL), interincisal distance, and OHRQoL (oral health-related quality of life) were analyzed in all three groups of subjects. Primary SS and dcSSc patients had statistically significant lower values of UWSFR (0.20; 0.38 vs. 0.91 mL/min) and SWSFR (0.56; 0.70 vs. 1.64 mL/min) compared with control subjects (p < 0.001, Kruskal-Wallis test). Salivary pH values were statistically significantly lower in pSS and dcSSc patients compared with control subjects (6.00; 6.25 vs. 7.00, respectively) (p < 0.001, Kruskal-Wallis test). The DMFT index of dcSSc patients was higher (28.50) and statistically significant compared to control subjects (20.00) (p = 0.01). The prevalence of periodontitis was the same in pSS and dcSSc patients and control subjects (p = 0.384). Primary SS and dcSSc patients had a statistically significant decreased interincisal distance compared to control subjects (43.80; 38.00 vs. 48.00) (p = 0.003 and p < 0.001, respectively). Primary SS and dcSSc patients show decreased UWSFR and SWSFR, salivary pH values closer to an acidic medium, higher DMFT index, higher prevalence of periodontitis, decreased interincisal distance, and poorer OHRQoL, i.e., poor oral and periodontal health.

The current regenerative medicine approaches of craniofacial diseases: A narrative review

Craniofacial deformities (CFDs) develop following oncological resection, trauma, or congenital disorders. Trauma is one of the top five causes of death globally, with rates varying from country to country. They result in a non-healing composite tissue wound as they degenerate in soft or hard tissues. Approximately one-third of oral diseases are caused by gum disease. Due to the complexity of anatomical structures in the region and the variety of tissue-specific requirements, CFD treatments present many challenges. Many treatment methods for CFDs are available today, such as drugs, regenerative medicine (RM), surgery, and tissue engineering. Functional restoration of a tissue or an organ after trauma or other chronic diseases is the focus of this emerging field of science. The materials and methodologies used in craniofacial reconstruction have significantly improved in the last few years. A facial fracture requires bone preservation as much as possible, so tiny fragments are removed initially. It is possible to replace bone marrow stem cells with oral stem cells for CFDs due to their excellent potential for bone formation. This review article discusses regenerative approaches for different types of craniofacial diseases.

Mechanisms and clinical application potential of mesenchymal stem cells-derived extracellular vesicles in periodontal regeneration

Periodontitis is a high prevalence oral disease which damages both the hard and soft tissue of the periodontium, resulting in tooth mobility and even loss. Existing clinical treatment methods cannot fully achieve periodontal tissue regeneration; thus, due to the unique characteristics of mesenchymal stem cells (MSCs), they have become the focus of attention and may be the most promising new therapy for periodontitis. Accumulating evidence supports the view that the role of MSCs in regenerative medicine is mainly achieved by the paracrine pathway rather than direct proliferation and differentiation at the injured site. Various cells release lipid-enclosed particles known as extracellular vesicles (EVs), which are rich in bioactive substances. In periodontitis, EVs play a pivotal role in regulating the biological functions of both periodontal tissue cells and immune cells, as well as the local microenvironment, thereby promoting periodontal injury repair and tissue regeneration. As a cell-free therapy, MSCs-derived extracellular vesicles (MSC-EVs) have some preponderance on stability, immune rejection, ethical supervision, and other problems; therefore, they may have a broad clinical application prospect. Herein, we gave a brief introduction to MSC-EVs and focused on their mechanisms and clinical application in periodontal regeneration.

Synthesis, Characterization, Cytotoxicity Analysis and Evaluation of Novel Heterocyclic Derivatives of Benzamidine against Periodontal Disease Triggering Bacteria

Periodontal disease (PD) is multifactorial oral disease that damages tooth-supporting tissue. PD treatment includes proper oral hygiene, deep cleaning, antibiotics therapy, and surgery. Despite the availability of basic treatments, some of these are rendered undesirable in PD treatment due to side effects and expense. Therefore, the aim of the present study is to develop novel molecules to combat the PD triggering pathogens. The study involved the synthesis of 4-((5-(substituted-phenyl)-1,3,4-oxadiazol-2-yl)methoxy)benzamidine (5a-e), by condensation of 2-(4-carbamimidoylphenoxy)acetohydrazide (3) with different aromatic acids; and synthesis of 4-((4-(substituted benzylideneamino)-4H-1,2,4-triazol-3-yl)methoxy)benzamidine (6a-b) by treatment of compound 3 with CS₂ followed by hydrazination and a Schiff reaction with different aromatic aldehydes. Synthesized compounds were characterized based on the NMR, FTIR, and mass spectrometric data. To assess the effectiveness of the newly synthesized compound in PD, new compounds were subjected to antimicrobial evaluation against P. gingivalis and E. coli using the micro-broth dilution method. Synthesized compounds were also subjected to cytotoxicity evaluation against HEK-293 cells using an MTT assay. The present study revealed the successful synthesis of heterocyclic derivatives of benzamidine with significant inhibitory potential against P. gingivalis and E. coli. Synthesized compounds exhibited minimal to the absence of cytotoxicity. Significant antimicrobial potential and least/no cytotoxicity of new heterocyclic analogs of benzamidine against PD-triggering bacteria supports their potential application in PD treatment.

How Periodontitis or Periodontal Bacteria Can Influence Alzheimer's Disease Features? A Systematic Review of Pre-Clinical Studies

BACKGROUND

The negative effects of periodontitis on systemic diseases, including diabetes, cardiovascular diseases, and Alzheimer's disease (AD), have been widely described.

OBJECTIVE

This systematic review aimed to gather the current understanding of the pathophysiological mechanisms linking periodontitis to AD.

METHODS

An electronic systematic search of the PubMed/MEDLINE, Scopus, and Embase databases was performed using the following PECO question: How can periodontitis or periodontal bacteria influence Alzheimer's disease features?". Only preclinical studies exploring the biological links between periodontitis and AD pathology were included. This study was registered at the International Prospective Register of Systematic Reviews (PROSPERO), and the Syrcle and Camarades protocols were used to assess the risk of bias.

RESULTS

After a systematic screening of titles and abstracts (n = 3,307), thirty-six titles were selected for abstract reading, of which 13 were excluded (k = 1), resulting in the inclusion of 23 articles. Oral or systemic exposure to periodontopathogens or their byproducts is responsible for both in situ brain manifestations and systemic effects. Significant elevated rates of cytokines and amyloid peptides (Aβ) and derivate products were found in both serum and brain. Additionally, in infected animals, hyperphosphorylation of tau protein, hippocampal microgliosis, and neuronal death were observed. Exposure to periodontal infection negatively impairs cognitive behavior, leading to memory decline.

CONCLUSIONS

Systemic inflammation and brain metastatic infections induced by periodontal pathogens contribute to neuroinflammation, amyloidosis, and tau phosphorylation, leading to brain damage and subsequent cognitive impairment.