Host Modulation and Treatment of Periodontal Disease

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.

M2 Macrophage-Derived Extracellular Vesicles Reprogram Immature Neutrophils into Anxa1hi Neutrophils to Enhance Inflamed Bone Regeneration

Periodontitis is a microbiome-related inflammation that can lead to irreversible bone reduction and even tooth loss. This study reveals that macrophage polarization states significantly influence periodontal homeostasis, with M2 macrophage-derived extracellular vesicles (M2-EVs) playing a pivotal role in mitigating periodontitis-induced bone loss. Single-cell RNA sequencing of periodontal tissues treated with M2-EVs uncovered a unique Anxa1hi neutrophil subpopulation exhibiting pro-reparative properties. This subpopulation is characterized by immaturity and demonstrated osteogenic and angiogenic capabilities in vivo, partially mediated through the secretion of oncostatin M (OSM) signals. The findings suggest that this functional heterogeneity arises from M2-EVs disrupting the neutrophil maturation trajectory, with pivotal reprogramming genes, such as Acvrl1 and Fpr2, driving the differentiation of the Anxa1hi reparative subpopulation. This work underscores the potential of targeting M2 macrophage-neutrophil interactions to promote the regeneration of inflamed bone tissues.

The active ingredients and targets of Kouqiangjie formula on periodontitis: a multi-approach study

Periodontitis (PD) is a complex oral inflammatory disease with diverse pathogenic factors, demanding effective multi-target therapeutic approaches. Traditional Chinese Medicine (TCM) formulations, like the Kouqiangjie Formula (KQJF), hold potential as alternative therapies due to their multiple pharmacological effects. This study comprehensively investigated the key active ingredients and molecular targets of KQJF in treating PD through a combination of network pharmacology, machine learning, Mendelian randomization (MR), and experimental validation. The active components and targets of KQJF were identified via the TCMSP and HERB databases, while PD-related genes were sourced from GeneCards, CTD, and DisGeNET. Gene expression data from GEO datasets enabled differential expression analysis. Machine learning models, including Random Forest (RF) and Support Vector Machine (SVM), were employed to evaluate the diagnostic potential of gene sets. Molecular docking was utilized to assess the interactions between active ingredients and targets, and MR analysis was conducted to explore the causal relationships with PD. Experimental validation was carried out using a rat model. The results indicated that KQJF consists of 193 active compounds that target 561 proteins, with a significant overlap of 272 targets related to PD. Key compounds such as luteolin, linolenic acid, and naringenin were identified. The SVM model demonstrated excellent predictive performance, with an AUC of 0.954. MR analysis revealed a significant causal effect of the CASP3 gene on the risk of PD (OR = 1.595, p = 0.015). Experimental findings showed that these compounds could reduce the expression of CASP3 and improve the integrity of periodontal tissues. In conclusion, luteolin, linolenic acid, and naringenin are the core compounds in KQJF, and CASP3 is an important target. This study emphasizes the great potential of KQJF for PD treatment and provides a solid data base for the development of new therapeutic strategies.

Construction of Chitosan Oligosaccharide-Coated Nanostructured Lipid Carriers for the Sustained Release of Strontium Ranelate

BACKGROUND

Strontium ranelate (SR) is an effective bone regeneration drug; however, its low bioavailability and strong hydrophilicity cause a strong cytotoxicity, venous thrombosis, and allergic reactions when administered in its free form. This study aims to enhance the SR bioavailability by utilizing nanostructured lipid carriers (NLC) as a drug delivery system (DDS).

METHODS

To improve the drug delivery efficiency and sustained release of the NLC, their surfaces were coated with chitosan oligosaccharide (COS), a natural polymer. The synthesis of COS-NLC was confirmed by measuring particle size and zeta potential, while surface morphology was evaluated using atomic force microscopy (AFM). SR loading efficiencies and release profiles were analyzed via reversed-phase high-performance liquid chromatography (RP-HPLC), and cytotoxicity was evaluated in mouse fibroblast L929 cells.

RESULTS

Particle characterization indicated that the COS coating slightly increased the particle size (i.e., from 128.99 ± 2.77 to 131.46 ± 2.13 nm) and zeta potential (i.e., from - 13.94 ± 0.49 to - 6.58 ± 0.32 mV) of the NLC. The COS-NLC exhibited a high SR-loading efficiency of ~ 86.31 ± 3.28%. An in vitro release test demonstrated an improved sustained release tendency of SR from the COS-NLC compared to that from the uncoated NLC. In cytotoxicity assays using L929 cells, the COS coating reduced the cytotoxicity of the formulated DDS, and the SR-COS-NLC exhibited a 1.4-fold higher cell regeneration effect than SR alone.

CONCLUSION

These findings suggest that the developed COS-NLC serve as an effective and biocompatible DDS platform for the delivery of poorly bioavailable drugs.

Effect of photobiomodulation with different wavelengths on periodontal repair in non-hyperglycemic and hyperglycemic rats

BACKGROUND

Hyperglycemic conditions is associated with more severe periodontitis and poorer outcomes after nonsurgical periodontal treatment (NPT). Then, these patients are candidates for adjunctive therapy associated with NPT. This study evaluates the effect of photobiomodulation (PBMT) at different wavelengths on periodontal repair in non-hyperglycemic/hyperglycemic animals.

MATERIALS AND METHODS

Sixty-four rats were submitted to induction of periodontitis by ligatures. Hyperglycemia was induced in half of these animals, whereas the other half remained non-hyperglycemic. The animals were subdivided into 4 groups according to the PBMT protocol applied at the time of ligature removal (n = 8): CTR: Without PBMT; IRL: PBMT with infrared laser (808 nm); RL: PBMT with red laser (660 nm); and RL-IRL: PBMT with red (660 nm) and infrared laser (808 nm). After a period of 7 days, the animals were euthanized. The parameters assessed by microtomography were the bone volume relative to total tissue volume (BV/TV%), distance from the cemento-enamel junction to the top of the bone crest (CEJ-CB), trabecular thickness, space between trabeculae, and number of trabeculae. Additionally, the percentage of inflammatory cells, blood vessels, and connective tissue matrix were assessed by histomorphometric analysis.

RESULTS

PBMT reduced bone loss and increased trabecular density in hyperglycemic animals (p < .05), with RL being more effective in reducing linear bone loss (CEJ-CB), whereas RL-IRL was more effective in maintaining BV/TV%. PBMT reduced blood vessels and increased the connective tissue component in hyperglycemic animals (p < .05). RL-IRL reduced inflammatory cells regardless of the systemic condition of the animal (p < .05).

CONCLUSION

PBMT (RL, RL-IRL) improves the repair of periodontal tissues in hyperglycemic animals.

Alpha-Ketoglutarate Alleviates Systemic Lupus Erythematosus-Associated Periodontitis in a Novel Murine Model

AIM

To establish a reproducible experimental animal model for systemic lupus erythematosus (SLE)-associated periodontitis (PD), investigate the effects of SLE on PD and assess the therapeutic potential of alpha-ketoglutarate (αKG) for SLE-PD treatment.

MATERIALS AND METHODS

An SLE-PD murine model was established via ligature-induced PD in MRL-lpr strain, with MRL/MpJ strain as a non-SLE control. The periodontal state was assessed using micro-CT, real-time PCR, histology, immunofluorescence and flow cytometry assays. αKG levels were analysed, and a thermoresponsive gel was designed as a periodontal dimethyl (DM)-αKG delivery system. αKG levels were analysed in gingival crevicular fluid (GCF) of PD patients with or without SLE.

RESULTS

SLE significantly increased the periodontal inflammation and bone resorption in the SLE-PD model. αKG levels in GCF were lower in PD patients with SLE than in PD patients without SLE. Decreased αKG levels in the gingiva and macrophage M1/M2 imbalance were observed in SLE-PD mice. However, DM-αKG thermoresponsive gel effectively alleviated the periodontal inflammation, bone resorption and macrophage M1/M2 imbalance in SLE-PD mice.

CONCLUSIONS

Our study established, for the first time, a novel SLE-PD murine model and revealed that SLE increases the severity of PD in vivo. Our findings highlight the therapeutic potential of αKG for SLE-associated PD.

Monocytic myeloid-derived suppressor cells contribute to the exacerbation of bone destruction in periodontitis

BACKGROUND

Periodontitis (PD) is a chronic infectious and inflammatory disease characterized by alveolar bone loss. The distinctive activity of immune cells critically exacerbates bone resorption in PD. Myeloid-derived suppressor cells (MDSCs) are known to contribute to various chronic inflammatory conditions, but their role in the pathogenesis and progression of PD remains poorly understood.

METHODS

We used single-cell transcriptomic analysis with human gingival samples and animal models of experimental periodontitis to examine the role of M-MDSCs in PD. We also explored the therapeutic effect of depleting MDSCs on PD in vivo. Additionally, the mechanisms of long non-coding RNA Neat1 and the pathway of NF-κB-dependent "canonical NLRP3 inflammasome activation" in MDSCs were investigated in PD.

RESULTS

In this study, we revealed that monocytic (M)-MDSCs were significantly increased in inflamed gingiva of PD patients compared to healthy individuals. Expansion of M-MDSCs was also observed in the mouse model of ligature-induced periodontitis, and depletion of MDSCs in PD mice could ameliorate alveolar bone loss and reduce periodontal inflammation. Mechanistically, we found that long non-coding RNA Neat1 was significantly upregulated in M-MDSCs, which achieved this proinflammatory effect by activating NF-κB signaling in PD. Furthermore, the pathway of NF-κB-dependent "canonical NLRP3 inflammasome activation" was confirmed in the PD mouse model, accompanied by increased secretion of proinflammatory cytokines that drive alveolar bone loss, including IL-1β, IL-6 and TNF-α.

CONCLUSIONS

In conclusion, this study highlights the pivotal proinflammatory role of M-MDSCs in PD and suggests that targeting these cells may represent a novel immunotherapeutic approach. Future research could focus on strategies to specifically target MDSCs for the treatment of periodontitis.

Effect of periodontal therapy on endothelial function and serum biomarkers in patients with periodontitis and established cardiovascular disease: a pilot study

Aim

To investigate the effect of periodontal therapy on endothelial function of subjects with periodontitis in stages III or IV and established cardiovascular disease.

Materials and methods

A triple-blinded, parallel groups, randomized clinical trial of 6 months duration, on patients with history of coronary heart disease and periodontitis in stages III or IV was performed. Intervention consisted of steps 1 (oral hygiene instructions and professional mechanical plaque removal) and 2 (subgingival instrumentation) of periodontal therapy, including an antiseptic mouth rinse for 7 days. Patients in the control group received only step 1, with the adjunctive use of a fluoride-containing mouth rinse. Endothelial function (flow-mediated dilation [FMD]) and carotid intima-media thickness (cIMT) at baseline, 3 and 6 months, and serum markers of inflammation and cell adhesion at 3 days, 10 days, 3 and 6 months after therapy, were evaluated. Demographic characteristics, cardiovascular risk factors, history of cardiovascular diseases, medication intake, lipids profile, blood pressure, and periodontal outcomes were also evaluated. Student T, Mann-Whitney U, Chi-square and Fisher-exact tests were performed along with repeated measures ANOVA with post hoc Bonferroni's corrections.

Results

Thirty-five patients were included. In the test group, improvements in pocket depth, bleeding on probing and suppuration at 6 months were significantly better than in control patients. Reductions in mean FMD [test group -3.43%; 95% confidence interval-CI [-2.68; 9.54], p = 0.487; control group -6.75%; 95% CI [1.29; 12.22], p = 0.012] and cIMT (test group -0.05 mm; 95% CI [0.01; 0.10], p = 0.014; control group -0.01 mm; 95% CI [-0.03; 0.05], p = 1.000) were observed in both groups from baseline to 6 months, without significant intergroup differences at any time-point. Differences between groups in serum inflammatory markers were detected at baseline and 3 days for interleukin (IL)-18, and at 10 days for IL-8.

Conclusion

Preliminary results from the present pilot study showed that steps 1 and 2 of periodontal treatment in subjects with periodontitis in stages III-IV and established cardiovascular disease induced improvements in cIMT and periodontal outcomes, although changes in FMD were not observed.

Clinical Trial Registration

clinicaltrials.gov, Identifier, database (NCT02716259).

Emerging therapeutic strategies targeting bone signaling pathways in periodontitis

Periodontitis is a multifactorial immune-mediated disease exacerbated by dysregulated alveolar bone homeostasis. Timely intervention is crucial for disease management to prevent tooth loss. To successfully manage periodontitis, it is imperative to understand the cellular and molecular mechanisms involved in its pathogenesis to develop novel treatment modalities. Non-surgical periodontal therapy (NSPT) such as subgingival instrumentation/debridement has been the underlying treatment strategy over the past decades. However, new NSPT approaches that target key signaling pathways regulating alveolar bone homeostasis have shown positive clinical outcomes. This narrative review aims to discuss endogenous bone homeostasis mechanisms impaired in periodontitis and highlight the clinical outcomes of preventive periodontal therapy to avoid invasive periodontal therapies. Although the anti-resorptive therapeutic adjuncts have demonstrated beneficial outcomes, adverse events have been reported. Diverse immunomodulatory therapies targeting the osteoblast/osteoclast (OB/OC) axis have shown promising outcomes in vivo. Future controlled randomized clinical trials (RCT) would help clinicians and patients in the selection of novel preventing therapies targeting key molecules to effectively treat or prevent periodontitis.

Probiotic Therapy as an Adjuvant in the Treatment of Periodontal Disease: An Innovative Approach

Background and Objectives: Periodontal inflammation, often linked to oral microbiota dysbiosis dominated by pathogenic bacteria, remains a significant challenge in periodontitis management. Traditional periodontal therapies primarily reduce the bacterial load but fail to restore the microbiota balance. Probiotics offer a promising therapeutic adjunct with their ability to enhance beneficial bacteria. This study investigates the effects of probiotics on the oral microbiota, inflammatory markers (IL-1β, TNF-α), and clinical parameters (gingival index, bleeding index, and periodontal pocket depth). Materials and Methods: In this pilot study, 80 patients with moderate-to-severe periodontitis were assigned to two groups. Group A received standard periodontal therapy (non-surgical periodontal therapy (NSPT)) with probiotic supplementation (Lactobacillus reuteri, 2 × 10⁹ CFU daily for 8 weeks), and Group B received standard treatment with a placebo. Microbiological changes were assessed via quantitative PCR, while inflammatory markers (IL-1β, TNF-α) were analyzed using ELISA. Clinical parameters, including the gingival index (GI), bleeding index (BI), and periodontal pocket depth (PPD), were measured at baseline (T0), 4 weeks (T1), and 8 weeks (T2) using standardized methods. Results: Probiotic therapy (Group A) significantly reduced the pathogenic bacteria and increased the beneficial bacteria levels compared to the placebo (p < 0.01). Inflammatory markers decreased by 37% (IL-1β) and 42% (TNF-α), while clinical parameters improved, with reductions in the gingival and bleeding indices (-1.5, -1.3) and a 2 mm decrease in the periodontal pocket depth (p < 0.01). Conclusions: Probiotics, as an adjunct to periodontal therapy, effectively restore the microbiota balance, reduce inflammation, and improve clinical outcomes in periodontitis.

Unraveling the Applicability of LbL Coatings for Drug Delivery in Dental Implant-Related Infection Treatment

Peri-implantitis is an inflammatory condition caused by bacterial biofilms adhered on dental implant surfaces that cause progressive tissue destruction from the host's inflammatory response. The adverse effects of peri-implantitis progression can go beyond just losing the implant. This highlights the importance of implementing strategies to stabilize disease in the short term. Layer-by-layer (LbL) assembly is a promising avenue in the field of peri-implantitis management due to its applicability with a variety of substances, in addition to being an easy, versatile, and flexible process for multilayer formation to act directly in the affected site. In this Review, our objective is to offer comprehensive chemical and biological insights into the LbL system, clarifying its specific application as antimicrobial coatings, with concern for the physical site and purpose. Additionally, we delve deeper into the concepts of onset and progression of peri-implantitis, aiming to elucidate the precise indications for employing the LbL system as a coating for implant abutments in peri-implantitis treatment. Finally, we correlate the chemical composition of the LbL system with its functionality while also addressing the challenges posed by the uncontrolled environment of the oral cavity, which ultimately restricts its clinical applicability.

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.

Interaction of the Systemic Inflammatory State, Inflammatory Mediators, and the Oral Microbiome

Humans are biological units that host numerous microbial symbionts and their genomes, which together form a superorganism or holobiont. Changes in the balance of the oral ecosystem can have consequences for both general and oral health, such as cavities, gingivitis, and periodontitis. Periodontitis is initiated by a synergistic and dysbiotic microbial community that causes local inflammation and destruction of the tooth's supporting tissues, potentially leading to systemic inflammation. This inflammation caused by periodontal disease has been associated with various systemic alterations, and the immune system is largely responsible for the body's exacerbated response, which can induce and exacerbate chronic conditions. Studies indicate that subgingival microorganisms found in periodontitis reach the bloodstream and are distributed throughout the body and, therefore, can be found in distant tissues and organs. Among all diseases associated with periodontal disease, diabetes mellitus presents the strongest and most elucidated link, and its bidirectional relationship has already been demonstrated. Chronic hyperglycemia favors the worsening of periodontal parameters, while the aggravation of periodontal parameters can promote an increase in glycemic indexes. Other systemic diseases have been related to periodontitis, such as Alzheimer's, chronic kidney disease, atherosclerosis, and respiratory diseases. The importance of periodontal control may suggest a reduction in the chances of developing chronic inflammatory diseases because these two alterations often share inflammatory pathways and, for this reason, may influence each other.

Recent findings on metabolomics and the microbiome of oral bacteria involved in dental caries and periodontal disease

Periodontal disease is characterized by bacterial toxins within the oral biofilm surrounding the teeth, leading to gingivitis and the gradual dissolution of the alveolar bone, which supports the teeth. Notably, symptoms in the early stages of the disease are often absent. Similarly, dental caries occurs when oral bacteria metabolize dietary sugars, producing acids that dissolve tooth enamel and dentin. These bacteria are commonly present in the oral cavity of most individuals. Metabolomics, a relatively recent addition to the "omics" research landscape, involves the comprehensive analysis of metabolites in vivo to elucidate pathological mechanisms and accelerate drug discovery. Meanwhile, the term "microbiome" refers to the collection of microorganisms within a specific environmental niche or their collective genomes. The human microbiome plays a critical role in health and disease, influencing a wide array of physiological and pathological processes. Recent advances in microbiome research have identified numerous bacteria implicated in dental caries and periodontal disease. Additionally, studies have uncovered various pathogenic factors associated with these microorganisms. This review focuses on recent findings in metabolomics and the microbiome, specifically targeting oral bacteria linked to dental caries and periodontal disease. We acknowledge the limitation of relying exclusively on the MEDLINE database via PubMed, while excluding other sources such as gray literature, conference proceedings, and clinical practice guidelines.

Effects of host modulation through omega-3 dietary supplementation on inflammatory outcomes in periodontitis: a scoping review

OBJECTIVE

Inflammation causes the progressive destruction of the supporting tissues around teeth in patients with periodontitis. Therefore, this study aimed to investigate the immunological effects of omega-3 polyunsaturated fatty acids (n-3 PUFAs) as adjunctive therapy in patients with periodontal disease and identify potential biomarkers for the disease.

METHODS

This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to investigate the impact of omega-3 therapy with or without acetylsalicylic acid on the immunological parameters of periodontal treatment. Eligible studies included those conducted on patients with normoglycemia and diabetes, published after 2002 in English, and containing relevant keywords. The exclusion criteria included pre-2002 publications, literature reviews, animal studies, and articles without immunological analysis. This review involved careful study selection by two double-blind researchers using the Rayyan software, with data extraction and analysis performed by the third and fourth reviewers.

RESULTS

Seven randomized clinical trials that compared control/placebo and n-3 PUFA groups or the follow-ups of the n-3 PUFA groups were included. The concentration of inflammatory cytokines was reduced following dietary supplementation with n-3 PUFA in the reviewed studies. Specifically, IL-1β, TNF-α, IL-6, and RANKL levels were reduced after dietary supplementation with n-3 PUFA as an adjunctive therapy for periodontitis. Changes in inflammatory outcomes were associated with the clinical benefits of periodontitis. However, significant divergence in the evaluated inflammatory markers, samples, and methods impairs direct comparisons and quantitative analyses in the available literature.

CONCLUSION

This study highlights the need for clinical trials to advance our understanding and assessment of inflammatory outcomes in patients with periodontitis.

Exploring the Impact of Biological Agents on Protecting Against Experimental Periodontitis: A Systematic Review of Animal-Based Studies

Aim: This systematic review was aimed at addressing the focused question: What is the protective potential of biological agents against alveolar bone resorption during the progression of experimental periodontitis (EP)? Material and Methods: The study protocol was registered in the Open Science Framework database (doi:10.17605/OSF.IO/3P2HY). A comprehensive literature search was conducted across PubMed, Web of Science, Cochrane Library, Scopus, and Embase databases up to December 2023. Inclusion criteria consisted of preclinical studies in animal models of EP that examined the effects of biological agents on preventing periodontal bone loss and reducing tissue inflammation. Studies were excluded if they (i) used non-EP animal models; (ii) focused on antimicrobial agents; (iii) centered on prebiotics or probiotics; (iv) evaluated compounds not classified as biologicals; or (v) included randomized clinical trials, clinical studies, or reviews. Eligibility was determined based on the PI/ECOs framework, and study quality was assessed using the SYRCLE risk-of-bias tool. Results: After screening an initial pool of 5236 records from databases, registries, and hand searches, 39 studies met the inclusion criteria. A total of 23 biological agents were evaluated across these studies. The majority of studies employed the ligature-induced model of EP to test the effectiveness of biologicals as preventive or therapeutic interventions. The dosage of biological agents and the duration of disease induction varied depending on the EP model. In all studies, the main outcome-alveolar bone loss, a hallmark of EP-was significantly inhibited by biological agents, which also reduced proinflammatory mediators when compared to untreated controls. A key strength of this review is the high number of studies included, most of which were classified as having low risk of bias. However, a notable limitation is the absence of a meta-analysis, the short follow-up periods in the included studies, and the heterogeneity among the compound dosages and route of administration. Conclusion: This systematic review demonstrates that biological agents are effective in reducing bone loss and mitigating inflammation during EP progression. Randomized clinical trials are needed to confirm these findings in human populations.

TRPV1 Regulates Proinflammatory Properties of M1 Macrophages in Periodontitis Via NRF2

Periodontitis, characterized by progressive alveolar bone destruction, leads to the loss of attachment and stability of the affected teeth. Macrophages, especially the proinflammatory M1 subtype, are key in periodontitis pathogenesis, driving the disease's inflammatory and destructive processes. Despite existing insight into their involvement, comprehensive understanding of the underlying molecular mechanisms remains limited. TRPV1 is a non-selective cation channel protein and is known to regulate cellular function and homeostasis in macrophages. Our research objective was to investigate the impact of TRPV1 on the proinflammatory attributes of M1 macrophages in periodontal tissues, exploring potential mechanistic pathways. A mouse model of periodontitis was established using Porphyromonas gingivalis inoculation and ligature application around the maxillary second molar. Immunohistological analysis showed a significant reduction in macrophage TRPV1 expression in periodontitis-induced mice. Treatment with capsaicin, a TRPV1 agonist, was observed to effectively elevate TRPV1 expression in these macrophages. Furthermore, micro-computed tomography analysis revealed a marked decrease in alveolar bone resorption in the capsaicin -treated group, compared with vehicle and healthy control groups. Our in vitro findings show that capsaicin treatment successfully attenuated LPS-induced TNF-α and IL-6 production in macrophages, mediated through NRF2 activation, consequently reducing intracellular ROS levels. These findings suggest that TRPV1 agonists, through modulating M1 macrophage activity and up-regulating TRPV1, could be a novel therapeutic approach in periodontal disease management.

Humic Acid Derived from Vermicompost Inhibits Alveolar Bone Degradation and Protects Against Renal Injury in an Experimental Model of Periodontitis

Background: Periodontal disease (PD) leads to the destruction of supportive tissues through an inflammatory response induced by biofilm accumulation. This low-grade systemic inflammation from PD increases the risk of comorbidities. Among potential therapeutic agents for PD, humic acids (HAs) are notable for their anti-inflammatory and immunomodulatory properties. This study aimed to evaluate the effects of varying HA doses on PD progression in an experimental model. Methods: Fifty-four Wistar rats were assigned to six groups (n = 8 each): control, PD, PD + 40 mg/kg HA, PD + 80 mg/kg HA, PD + 160 mg/kg HA, and PD + 320 mg/kg HA. HA from vermicompost was administered daily by gavage for 28 days, with PD induced by ligature on day 14. Post-euthanasia, mandibular samples were analyzed histomorphometrically for bone loss and osteocyte density. Alveolar bone topography and elemental composition were examined using Scanning Electron Microscopy (SEM) coupled with Energy Dispersive Spectroscopy (EDS). Renal and hepatic tissues were assessed histopathologically. Data were analyzed with Analysis of Variance (ANOVA) and Duncan's test. Results: HA-treated animals showed reduced epithelial attachment loss and alveolar bone loss, with improved bone quality parameters, such as reduced pore number and diameter and increased osteocyte density compared to the PD group. Renal lesions observed in PD animals were mitigated at 40 and 80 mg/kg HA doses. Conclusions: HA treatment improves alveolar bone integrity and, at lower doses, reduces PD-induced renal lesions.

Thermosensitive hydrogel doped with osteoconductive fillers for the treatment of periodontitis periapicalis chronica: from synthesis to clinical trial

Herein, a chitosan-based thermosensitive hydrogel (CH) containing hydroxyapatite (HAp), poly(lactic acid) (PLDLLA) or their mixture is proposed as an innovative, biomimetic composition with antimicrobial and bone-forming properties for guided bone regeneration. The modified hydrogels were synthesized and characterized to verify their suitability for the treatment of periodontitis periapicalis chronica. Compared to the unmodified hydrogel, both CH_HAp and CH_PLDLLA revealed improved mechanical properties, as evidenced by rotational rheology. FTIR analysis proved that no chemical interplay existed between the components. All the tested samples displayed no cytotoxicity against osteoblast-like cell culture and confirmed antimicrobial features, both crucial from an application perspective. Radiation sterilization dosage was tailored for the tested samples to maintain sterility for a minimum of 8 weeks of storage and limit crosslinking of the samples. Finally, the hydrogel was used in a clinical trial to treat a patient with chronic inflammation of periapical tissues in teeth 26 and 27. The medical procedure proved the safety, nontoxicity, non-allergenicity, and, most importantly, bone-forming properties of the hydrogel formulation. The kinetics of new bone formation was analyzed in-depth using graphical cross-sections of anatomical structures obtained from pre- and post-operative CBCT scans.

Prospective and challenges of locally applied repurposed pharmaceuticals for periodontal tissue regeneration

Periodontitis is a persistent inflammatory condition that causes periodontal ligament degradation, periodontal pocket development, and alveolar bone destruction, all of which lead to the breakdown of the teeth's supporting system. Periodontitis is triggered by the accumulation of various microflora (especially anaerobes) in the pockets, which release toxic substances and digestive enzymes and stimulate the immune system. Periodontitis can be efficiently treated using a variety of techniques, both regional and systemic. Effective therapy is dependent on lowering microbial biofilm, minimizing or eradicating pockets. Nowadays, using local drug delivery systems (LDDSs) as an adjuvant therapy to phase I periodontal therapy is an attractive option since it controls drug release, resulting in improved efficacy and lesser adverse reactions. Choosing the right bioactive agent and mode of delivery is the foundation of an efficient periodontal disease management approach. The objective of this paper is to shed light on the issue of successful periodontal regeneration, the drawbacks of currently implemented interventions, and describe the potential of locally delivered repurposed drugs in periodontal tissue regeneration. Because of the multiple etiology of periodontitis, patients must get customized treatment with the primary goal of infection control. Yet, it is not always successful to replace the lost tissues, and it becomes more challenging as the defect gets worse. Pharmaceutical repurposing offers a viable, economical, and safe alternative for non-invasive, and predictable periodontal regeneration. This article clears the way in front of researchers, decision-makers, and pharmaceutical companies to explore the potential, effectiveness, and efficiency of the repurposed pharmaceuticals to generate more economical, effective, and safe topical pharmaceutical preparations for periodontal tissue regeneration.

An NIR-propelled janus nanomotor with enhanced ROS-scavenging, immunomodulating and biofilm-eradicating capacity for periodontitis treatment

Periodontitis is an inflammatory disease caused by bacterial biofilms, which leads to the destruction of periodontal tissue. Current treatments, such as mechanical cleaning and antibiotics, struggle to effectively address the persistent biofilms, inflammation, and tissue damage. A new approach involves developing a Janus nanomotor (J-CeM@Au) by coating cerium dioxide-doped mesoporous silica (CeM) with gold nanoparticles (AuNPs). This nanomotor exhibits thermophoretic motion when exposed to near-infrared (NIR) laser light due to the temperature gradient produced by the photothermal effects of asymmetrically distributed AuNPs. The NIR laser provides the energy for propulsion and activates the nanomotor's antibacterial properties, allowing it to penetrate biofilms and kill bacteria. Additionally, the nanomotor's ability to scavenge reactive oxygen species (ROS) can modulate the immune response and create a regenerative environment, promoting the healing of periodontal tissue. Overall, this multifunctional nanomotor offers a promising new approach for treating periodontitis by simultaneously addressing biofilm management and immune modulation with autonomous movement.

Systemic Factors Affecting Prognosis in Periodontics: Part II

This study gives an insight into certain systemic conditions and factors such as nutrition, age, hematological disorders, hypertension, smoking, obesity, and metabolic syndrome that have a notable effect on the periodontium. The review highlights the importance of taking these factors into consideration in periodontal therapy and their impact on the prognosis of periodontal therapies. The other systemic factors are discussed in detail elsewhere in the special issue.

Inflammation indices in association with periodontitis and cancer

Inflammation is a complex physiological process that plays a pivotal role in many if not all pathological conditions, including infectious as well as inflammatory diseases, like periodontitis and autoimmune disorders. Inflammatory response to periodontal biofilms and tissue destruction in periodontitis is associated with the release of inflammatory mediators. Chronic inflammation can promote the development of cancer. Persistence of inflammatory mediators plays a crucial role in this process. Quantification and monitoring of the severity of inflammation in relation to cancer is essential. Periodontitis is mainly quantified based on the severity and extent of attachment loss and/or pocket probing depth, in addition with bleeding on probing. In recent years, studies started to investigate inflammation indices in association with periodontal diseases. To date, only few reviews have been published focusing on the relationship between blood cell count, inflammation indices, and periodontitis. This review presents a comprehensive overview of different systemic inflammation indices, their methods of measurement, and the clinical applications in relation to periodontitis and cancer. This review outlines the physiological basis of inflammation and the underlying cellular and molecular mechanisms of the parameters described. Key inflammation indices are commonly utilized in periodontology such as the neutrophil to lymphocyte ratio. Inflammation indices like the platelet to lymphocyte ratio, platelet distribution width, plateletcrit, red blood cell distribution width, lymphocyte to monocyte ratio, delta neutrophil index, and the systemic immune inflammation index are also used in hospital settings and will be discussed. The clinical roles and limitations, relationship to systemic diseases as well as their association to periodontitis and treatment response are described.

Phosphorylation of Serine 536 of p65(RelA) Downregulates Inflammatory Responses

Nuclear factor-κB (NF-κB) is a transcription factor that regulates the expression of various genes involved in inflammatory diseases and immune responses. Recently, a novel transcriptional regulatory mechanism of NF-κB involving the phosphorylation of serine 536 (534 in mice; S534) of its p65 subunit was reported; however, further research is required to elucidate the physiological role of S534 phosphorylation. Therefore, we generated S534A knock-in (KI) mice, in which the S534 of p65 was substituted with alanine. Similar to the wild-type (WT) mice, S534A KI mice developed normally. After stimulation with tumor necrosis factor α (TNFα), mouse embryonic fibroblasts (MEFs) derived from S534A KI mice exhibited increased target gene expression compared with that in the WT MEFs, which was induced by long-term binding of p65 to DNA. According to comprehensive gene expression analysis after stimulation with TNFα, the expression of genes p65ted to inflammatory and immune responses was increased, and the expression of genes p65ted to lipolysis was decreased in S534A KI MEFs. Analyses of a periodontal disease model established using WT and S534A KI mice revealed that alveolar bone resorption was enhanced in S534A KI mice owing to an increase in the number of osteoclasts, which was not attributed to the differentiation of osteoclast precursor cells but to an increased expression of interleukin-1β and receptor activator of NF-κB ligand in the periodontal tissue. Hence, phosphorylation of S536 negatively regulates inflammatory responses in vitro and in vivo.

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

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

Which types of bony changes in the maxillary sinus indicate chronic sinusitis?

OBJECTIVES

To determine which types of bone lesion (spicules, lobules, porous bone) in the maxillary sinus indicate sinusitis METHODS: Subadjacent dental disease is a cause of maxillary sinusitis; if a lesion type indicates sinusitis it should be more common above diseased posterior maxillary teeth than a lesion type that is not indicative of sinusitis. The study sample is a British Mediaeval human skeletal collection.

RESULTS

Porous bone lesions (chiefly new bone deposits) in maxillary sinuses are associated with subadjacent dental disease; spicules/lobules of bone in the sinus are not.

CONCLUSIONS

The results support the idea that porous lesions indicate sinusitis but the spicules/lobules may not. Spicules, lobules and porous lesions within the maxillary sinus should be analysed separately in biocultural studies; it would be prudent to regard only the porous lesions as indicative of sinusitis.

SIGNIFICANCE

Maxillary sinusitis is commonly used as a health indicator in palaeopathology, and spicular deposits are generally the most common type of alterations. By assuming that they are indicative of sinusitis we may have been greatly overestimating the prevalence of bony sinusitis in the past.

LIMITATIONS

These conclusions are provisional. Further work on larger, more diverse samples, together with more detailed anatomical studies on lesion location and structure is ongoing.

Cytokines profile in gingival crevicular fluid of subjects wearing fixed dental prostheses: a systematic review and meta-analysis

BACKGROUND

Fixed dental prostheses (FDP) can affect the production of inflammatory cytokines causing damage to periodontal tissues. A systematic review and meta-analysis was carried out with the following two objectives: (1) to determine the prevalence and function of the different inflammatory cytokines present in gingival crevicular fluid (GCF) of teeth with metal-ceramic (M/C) and all-ceramic (A-Cs) prostheses, and (2) to analyze and compare the levels of inflammatory cytokines in GCF of teeth with M/C and A-Cs prostheses.

METHODS

The protocol followed PRISMA and Cochrane guidelines and was registered in the OSF:10.17605/OSF.IO/RBHJU. A digital search was conducted in the databases PubMed/MEDLINE, Cochrane Library, Dentistry & Oral Sciences Source, Scopus, Web of Science, ScienceDirect, and Google Scholar, from July 15th, 2000 to March 1st, 2024. Study quality was assessed using the JBI tool for cross-sectional and longitudinal studies. A meta-analysis was performed using a random-effects model to evaluate the concentration of IL-1β in GCF of teeth with FDP of M/C and A-Cs.

RESULTS

The search strategy provided a total of 8,172 articles, of which 14 investigations met the inclusion criteria. The total number of patients studied was 468 of whom 53% were women and the rest (47%) were men. The ages of the patients ranged from 19 to 73 years, with a mean age ± standard deviation (SD) of 38,5 ± 12,8 years. A total of 843 fixed dental prostheses were studied, of which 407 (48,27%) were M/C prostheses and 410 (48,63%) were A-Cs prostheses. We found that the levels of IL-1β, IL-1α, PGE2, NKA, CGRP, and CX3CL1 were increased in teeth with M/C prostheses compared to teeth with A-Cs prostheses. Meta-analysis revealed that there are no significant differences between IL-1β levels in GCF in teeth with M/C prostheses compared to teeth with A-Cs prostheses (SMD = 13.89 pg/ml (CI = -14.29-42.08), p =  > 0.05).

CONCLUSIONS

A trend toward increased levels of inflammatory cytokines was found in GCF of teeth with M/C prostheses compared to teeth with A-Cs prostheses.

Periodontal host-modulation therapy with avocado/soybean unsaponifiables in rats with arthritis

BACKGROUND

The aim of this study was to evaluate the effect of the avocado/soybean unsaponifiables (ASU) in the treatment of induced periodontitis in rats with experimental arthritis.

METHODS

Sixty rats were randomly assigned to 4 groups according to the type of treatment and the systemic condition of the animals: CTR-S: healthy animals in which saline solution (SS) was administered; ASU-S: healthy animals in which ASU (0.6 mg/kg) was administered; AR/ASU-S: animals with induced arthritis in which ASU was administered; AR-S: animals with induced arthritis in which SS was administered. Periodontitis was induced by ligatures, maintained for 15 days. Subsequently, the treatment was performed by scaling with hand instruments. The SS and ASU were administered daily by gavage until euthanasia of the animals that occurred at 7, 15 or 30 days after the scaling procedure (N.=5 animals/group). Bone resorption, inflammatory infiltrate composition, and osteoclastogenesis were assessed.

RESULTS

The AR-S group had greater bone loss, smaller amounts of fibroblasts and larger amounts of inflammatory cells than all other groups. In addition, the AR-S group had greater osteoclastogenesis in relation to the healthy animal groups.

CONCLUSIONS

The use of ASU improved the healing pattern after treatment for experimental periodontitis in animals with arthritis reducing the periodontal bone loss.

MyD88 exacerbates inflammation-induced bone loss by modulating dynamic equilibrium between Th17/Treg cells and subgingival microbiota dysbiosis

BACKGROUND

This study aimed to investigate the contribution of myeloid differentiation primary-response gene 88 (MyD88) on the differentiation of T helper type 17 (Th17) and regulatory T (Treg) cells and the emerging subgingival microbiota dysbiosis in Porphyromonas gingivalis-induced experimental periodontitis.

METHODS

Alveolar bone loss, infiltrated inflammatory cells, immunostained cells for tartrate-resistant acid phosphatase (TRAP), the receptor activator of nuclear factor-kB ligand (RANKL), and osteoprotegerin (OPG) were quantified by microcomputerized tomography and histological staining between age- and sex-matched homozygous littermates (wild-type [WT, Myd88+/+] and Myd88-/- on C57BL/6 background). The frequencies of Th17 and Treg cells in cervical lymph nodes (CLNs) and spleen were determined by flow cytometry. Cytokine expression in gingival tissues, CLNs, and spleens were studied by quantitative polymerase chain reaction (qPCR). Analysis of the composition of the subgingival microbiome and functional annotation of prokaryotic taxa (FAPROTAX) analysis were performed.

RESULTS

P. gingivalis-infected Myd88-/- mice showed alleviated bone loss, TRAP+ osteoclasts, and RANKL/OPG ratio compared to WT mice. A significantly higher percentage of Foxp3+CD4+ T cells in infected Myd88-/- CLNs and a higher frequency of RORγt+CD4+ T cells in infected WT mice was noted. Increased IL-10 and IL-17a expressions in gingival tissue at D14-D28 then declined in WT mice, whereas an opposite pattern was observed in Myd88-/- mice. The Myd88-/- mice exhibited characteristic increases in gram-positive species and species having probiotic properties, while gram-negative, anaerobic species were noted in WT mice. FAPROTAX analysis revealed increased aerobic chemoheterotrophy in Myd88-/- mice, whereas anaerobic chemoheterotrophy was noted in WT mice after P. gingivalis infection.

CONCLUSIONS

MyD88 plays an important role in inflammation-induced bone loss by modulating the dynamic equilibrium between Th17/Treg cells and dysbiosis in P. gingivalis-induced experimental periodontitis.

Association between periodontal disease and schizophrenia: a bidirectional two-sample Mendelian randomization study

The connection between periodontal disease (PD) and schizophrenia (SCZ) has been reported in observational studies, but it remains unclear. This research aims to examine the bidirectional causal impacts between PD and SCZ. The FinnGen consortium supplied summarized data on PD for 346,731 individuals (87,497 cases and 259,234 controls) of Finnish ancestry, and information on SCZ was acquired from the OpenGWAS repository, encompassing 127,906 individuals (52,017 cases and 75,889 controls) of European ancestry. Next, we conducted Mendelian randomization (MR) analysis to establish a causal inference relationship between PD and SCZ. The inverse variance weighted (IVW) method was utilized as the primary analysis. Additionally, some sensitivity analyses were utilized to verify the stability of the results. The analysis of IVW results indicated no impact of PD on SCZ (IVW OR = 1.10, 95% CI 0.97-1.24, P = 0.14). Nevertheless, the inverse relationship between PD and SCZ was identified through reverse MR analysis (IVW OR = 1.03, 95% CI 1.01-1.05, P = 0.002). The findings from MR-Egger, weighted median, simple mode, and weighted mode approaches aligned with the outcomes of the IVW method. Based on sensitivity analyses, horizontal pleiotropy is unlikely to distort causal estimates. This study presented the initial proof of a genetic causal relationship between SCZ and PD, albeit with a minimal impact. Further exploration is needed to gain a deeper understanding of this relationship. Furthermore, no genetic causal relationship between PD and SCZ was identified.

The Role of Different Types of Cannabinoids in Periodontal Disease: An Integrative Review

This integrative review addresses the potential of the Endocannabinoid System (ES) and cannabinoids in the pathogenesis and treatment of periodontal disease (PD). Cannabinoid receptors are expressed in healthy and inflamed periodontal tissues, indicating a potential regulatory role for SEC in oral homeostasis. Healthy periodontal cells express more CB1 receptors, while inflamed sites show increased CB2 receptors. This suggests a dynamic involvement of the SEC in the inflammatory response associated with PD. Cannabinoids such as cannabidiol (CBD) and cannabinoid receptor agonists such as HU-308, anandamide (AEA), and methanamide (Meta-AEA) have demonstrated promising therapeutic potential in studies. CBD has been associated with the control of bone resorption, antibacterial activity, and increased production of gingival fibroblasts, indicating effects in mitigating the progression of PD. HU-308 demonstrated preventive effects against alveolar bone loss, and anti-inflammatory, osteoprotective, and pro-homeostatic properties in animal models of periodontitis. AEA and Meta-AEA have anti-inflammatory effects by reducing pro-inflammatory mediators such as IL-1, IL-6, and TNF-α. The activation of cannabinoid receptors attenuates inflammatory processes, inhibits alveolar bone loss, exerts antibacterial effects, and promotes tissue repair. However, clinical trials are especially needed to validate these results and explore the therapeutic potential of cannabinoids in the treatment of PD in humans.

Investigating the Interplay: Periodontal Disease and Type 1 Diabetes Mellitus-A Comprehensive Review of Clinical Studies

Diabetes mellitus (DM) poses a significant challenge to global health, with its prevalence projected to rise dramatically by 2045. This narrative review explores the bidirectional relationship between periodontitis (PD) and type 1 diabetes mellitus (T1DM), focusing on cellular and molecular mechanisms derived from the interplay between oral microbiota and the host immune response. A comprehensive search of studies published between 2008 and 2023 was conducted to elucidate the association between these two diseases. Preclinical and clinical evidence suggests a bidirectional relationship, with individuals with T1DM exhibiting heightened susceptibility to periodontitis, and vice versa. The review includes recent findings from human clinical studies, revealing variations in oral microbiota composition in T1DM patients, including increases in certain pathogenic species such as Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans, along with shifts in microbial diversity and abundance. Molecular mechanisms underlying this association involve oxidative stress and dysregulated host immune responses, mediated by inflammatory cytokines such as IL-6, IL-8, and MMPs. Furthermore, disruptions in bone turnover markers, such as RANKL and OPG, contribute to periodontal complications in T1DM patients. While preventive measures to manage periodontal complications in T1DM patients may improve overall health outcomes, further research is needed to understand the intricate interactions between oral microbiota, host response, periodontal disease, and systemic health in this population.

Boric acid alleviates periodontal inflammation induced by IL-1β in human gingival fibroblasts

BACKGROUND

Boric acid (BA) has been found to have therapeutic effects on periodontal disease through beneficially affecting antibacterial, anti-viral, and anti-inflammatory actions.

METHODS

This study was conducted to determine the effect of BA on cell viability and on mRNA expressions of proinflammatory and anti-inflammatory cytokines and on oxidative stress enzymes induced by IL-1β (1 ng/mL) in Human Gingival Fibroblasts (HGF) cultured for 24 and 72 h in DMEM media. The BA concentrations added to the media were 0.09 %, 0.18 %, 0.37 %, and 0.75 %.

RESULTS

All of the BA concentrations increased the viability of cell cultured in DMEM media only, indicating that these concentrations were not toxic and actually beneficial to cell viability. The addition of 1 ng/m: of IL-1β decreased cell viability that was overcome by all concentrations of BA at both 24 and 72 h. The IL-1β addition to the media increased the expressions of the proinflammatory cytokines IL-1β, IL-6, IL-8, and IL-17; the anti-inflammatory cytokine IL-10; and the oxidative stress enzymes superoxide dismutase (SOD0 and glutathione peroxidase (GPX). The IL-1β induced increase mRNA expression of IL-1β was decreased at 24 h by the 0.37 % and 0.75 % BA additions to the media and decreased in a dose-dependent manner by all concentrations of BA at 72 h. The IL-1β induced increase in the expression of IL-6 was decreased in dose-dependent manner at 72 h by BA. All BA concentrations decreased the IL-1β induced expression of IL-8 at both 24 and 72 h. The induced increase in IL-17 by IL-1β was not significantly affected by the BA additions. The increase in the anti-inflammatory cytokine IL10 induced by IL-1β was increased further by all BA additions in dose dependent manner at both 24 and 72 h. The mRNA expressions of SOD and GPX increased by IL-1β were further increased by the 0.37 % and 0.75 % BA concentrations at 72 h.

CONCLUSIONS

These findings indicate that BA can significantly modulate the cytokines that are involved in inflammatory stress and reactive oxygen species action and thus could be an effective therapeutic agent in the treatment of periodontal disease.

Enhanced immunomodulation and periodontal regeneration efficacy of subgingivally delivered progranulin-loaded hydrogel as an adjunct to non-surgical treatment for Class II furcation involvement in dogs

AIM

To evaluate the effect of subgingival delivery of progranulin (PGRN)/gelatin methacryloyl (GelMA) complex as an adjunct to scaling and root planing (SRP) on an experimental periodontitis dog model with Class II furcation involvement (FI).

MATERIALS AND METHODS

A Class II FI model was established, and the defects were divided into four treatment groups: (a) no treatment (control); (b) SRP; (c) SRP + GelMA; (d) SRP + PGRN/GelMA. Eight weeks after treatment, periodontal parameters were recorded, gingival crevicular fluid and gingival tissue were collected for ELISA and RT-qPCR, respectively, and mandibular tissue blocks were collected for micro computed tomography (micro-CT) scanning and hematoxylin and eosin (H&E) staining.

RESULTS

The SRP + PGRN/GelMA group showed significant improvement in all periodontal parameters compared with those in the other groups. The expression of markers related to M1 macrophage and Th17 cell significantly decreased, and the expression of markers related to M2 macrophage and Treg cell significantly increased in the SRP + PGRN/GelMA group compared with those in the other groups. The volume, quality and area of new bone and the length of new cementum in the root furcation defects of the PGRN/GelMA group were significantly increased compared to those in the other groups.

CONCLUSIONS

Subgingival delivery of the PGRN/GelMA complex could be a promising non-surgical adjunctive therapy for anti-inflammation, immunomodulation and periodontal regeneration.

Reuterin isolated from the probiotic Lactobacillus reuteri promotes periodontal tissue regeneration by inhibiting Cx43-mediated the intercellular transmission of endoplasmic reticulum stress

OBJECTIVE

The present study aimed to evaluate the effects of reuterin, a bioactive isolated from the probiotic Lactobacillus reuteri (L. reuteri) on periodontal tissue regeneration, and provide a new strategy for periodontitis treatment in the future.

BACKGROUND

Data discussing the present state of the field: Probiotics are essential for maintaining oral microecological balance. Our previous study confirmed that probiotic L. reuteri extracts could rescue the function of mesenchymal stem cells (MSCs) and promote soft tissue wound healing by neutralizing inflammatory Porphyromonas gingivalis-LPS. Periodontitis is a chronic inflammatory disease caused by bacteria seriously leading to tooth loss. In this study, we isolated and purified reuterin from an extract of L. reuteri to characterize from the extracts of L. reuteri to characterize its role in promoting periodontal tissue regeneration and controlling inflammation in periodontitis.

METHODS

Chromatographic analysis was used to isolate and purify reuterin from an extract of L. reuteri, and HNMR was used to characterize its structure. The inflammatory cytokine TNFα was used to simulate the inflammatory environment. Periodontal ligament stem cells (PDLSCs) were treated with TNFα and reuterin after which their effects were characterized using scratch wound cell migration assays to determine the concentration of reuterin, an experimental periodontitis model in rats was used to investigate the function of reuterin in periodontal regeneration and inflammation control in vivo. Real-time PCR, dye transfer experiments, image analysis, alkaline phosphatase activity, Alizarin red staining, cell proliferation, RNA-sequencing and Western Blot assays were used to detect the function of PDLSCs.

RESULTS

In vivo, local injection of reuterin promoted periodontal tissue regeneration of experimental periodontitis in rats and reduced local inflammatory response. Moreover, we found that TNFα stimulation caused endoplasmic reticulum (ER) stress in PDLSCs, which resulted in decreased osteogenic differentiation. Treatment with reuterin inhibited the ER stress state of PDLSCs caused by the inflammatory environment and restored the osteogenic differentiation and cell proliferation functions of inflammatory PDLSCs. Mechanistically, we found that reuterin restored the functions of inflammatory PDLSCs by inhibiting the intercellular transmission of ER stress mediated by Cx43 in inflammatory PDLSCs and regulated osteogenic differentiation capacity.

CONCLUSION

Our findings identified reuterin isolated from extracts of the probiotic L. reuteri, which improves tissue regeneration and controls inflammation, thus providing a new therapeutic method for treating periodontitis.

Assessing Causal Relationships Between Periodontitis and Non-alcoholic Fatty Liver Disease: A Two-Sample Bidirectional Mendelian Randomisation Study

PURPOSE

To investigate the causality between periodontitis and non-alcoholic fatty liver disease (NAFLD) using a two-sample bidirectional Mendelian randomisation (MR) analysis.

MATERIALS AND METHODS

Genetic variations in periodontitis and NAFLD were acquired from genome-wide association studies (GWAS) using the Gene-Lifestyle Interaction in Dental Endpoints, a large-scale meta-analysis, and FinnGen consortia. Data from the first two databases were used to explore the causal relationship between periodontitis and NAFLD ("discovery stage"), and the data from FinnGen was used to validate our results ("validation stage"). We initially performed MR analysis using 5 single nucleotide polymorphisms (SNPs) in the discovery samples and 18 in the replicate samples as genetic instruments for periodontitis to investigate the causative impact of periodontitis on NAFLD. We then conducted a reverse MR analysis using 6 SNPs in the discovery samples and 4 in the replicate samples as genetic instruments for NAFLD to assess the causative impact of NAFLD on periodontitis. We further implemented heterogeneity and sensitivity analyses to assess the reliability of the MR results.

RESULTS

Periodontitis was not causally related to NAFLD (odds ratio [OR] = 1.036, 95% CI: 0.914-1.175, p = 0.578 in the discovery stage; OR = 1.070, 95% CI: 0.935-1.224, p = 0.327 in the validation stage), and NAFLD was not causally linked with periodontitis (OR = 1.059, 95% CI: 0.916-1.225, p = 0.439 in the discovery stage; OR = 0.993, 95% CI: 0.896-1.102, p = 0.901 in the validation stage). No heterogeneity was observed among the selected SNPs. Sensitivity analyses demonstrated the absence of pleiotropy and the reliability of our MR results.

CONCLUSION

The present MR analysis showed no genetic evidence for a cause-and-effect relationship between periodontitis and NAFLD. Periodontitis may not directly influence the development of NAFLD and vice versa.

Assessment of the Effect on Periodontitis of Antibiotic Therapy and Bacterial Lysate Treatment

Periodontitis is an inflammatory process that starts with soft tissue inflammation caused by the intervention of oral bacteria. By modulating local immunity, it is possible to supplement or replace current therapeutic methods. The aim of this study was to compare the effects of an immunostimulatory treatment with the antibiotherapy usually applied to periodontitis patients. On a model of periodontitis induced in 30 rats (divided into three equal groups) with bacterial strains selected from the human oral microbiome (Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Streptococcus oralis), we administered antibiotics, bacterial lysates and saline for 10 days. Clinically, no significant lesions were observed between the groups, but hematologically, we detected a decrease in lymphocyte and neutrophil counts in both the antibiotic and lysate-treated groups. Immunologically, IL-6 remained elevated compared to the saline group, denoting the body's effort to compensate for bone loss due to bacterial action. Histopathologically, the results show more pronounced oral tissue regeneration in the antibiotic group and a reduced inflammatory reaction in the lysate group. We can conclude that the proposed bacterial lysate has similar effects to antibiotic therapy and can be considered an option in treating periodontitis, thus eliminating the unnecessary use of antibiotics.

Association between antihyperlipidemic agents and the risk of chronic periodontitis in patients with hyperlipidemia: A population-based retrospective cohort study in Taiwan

BACKGROUND

The lipid-lowering and anti-inflammatory effects of statins and fibrates may ameliorate periodontitis. Patients with hyperlipidemia tend to have a worse periodontal status. This study assessed the association between the use of statins/fibrates and the incidence of chronic periodontitis in patients with hyperlipidemia in Taiwan.

METHODS

This retrospective cohort study enrolled patients newly diagnosed with hyperlipidemia between 2001 and 2012 from the 2000 Longitudinal Generation Tracking Database and followed them for 5 years. The study population was divided into four groups: statin monotherapy, fibrate monotherapy, combination therapy (both statins and fibrates), and control (neither statins nor fibrates). Each patient in the treatment group was matched at a ratio of 1:1 with a control. Chronic periodontitis risk was compared in the three study arms by using a Cox proportional hazard model.

RESULTS

Chronic periodontitis risk was reduced by 25.7% in the combination therapy group compared with the control group (adjusted hazard ratio [aHR], 0.743; 95% confidence interval (CI), 0.678-0.815). Low dose (<360 cumulative defined daily dose [cDDD]) and shorter duration (<2 years) of statin monotherapy seem to be associated with an increased risk of chronic periodontitis; high dose (≥720 cDDD/≥1080 cDDD) and longer duration (≥3 years) of statin/fibrate monotherapy may be correlated with a lower risk of periodontitis. Hydrophobic statin users had a lower chronic periodontitis risk than hydrophilic statin users.

CONCLUSION

Chronic periodontitis risk was lower in patients with hyperlipidemia on combination treatment with statins and fibrates, and the risk decreased when patients used statins or fibrates for >3 years.

Cubic liquid crystals containing propolis flavonoids as in situ thermo-sensitive hydrogel depots for periodontitis treatment: Preparation, pharmacodynamics and therapeutic mechanisms

Propolis has a long ethnopharmacological history for oral periodontal diseases treatment. Propolis flavonoids are main active components for anti-inflammation and tissue protection. However, the intractable dissolution properties of propolis flavonoids and complex oral environment pose great challenges for periodontal delivery. In addition, the therapeutic mechanism as well as the therapeutic correlation of inflammation resolution and tissue regeneration remain unclear for propolis flavonoids. In this study, we constructed an in situ thermosensitive depot systems using total flavonoids from propolis-loaded cubic liquid crystals (TFP-CLC) hydrogel for periodontal delivery. TFP-CLC inhibited inflammatory cell infiltration, reactive oxygen species and the expression of inflammatory cytokines of NF-κB and IL-1β. In addition, alveolar bone and collagen were significantly regenerated after TFP-CLC administration according to micro-CT and immunohistochemistry. Mechanism studies suggested that TFP-CLC alleviated inflammation and promoted alveolar bone repair via regulating TLR4/MyD88/NF-κB p65 and RANK/NF-κB signaling pathways, respectively. Correlation analysis further confirmed that the inflammatory resolution produced by TFP-CLC could accelerate periodontal tissue regeneration. In summary, TFP-CLC is a promising multifunctional in situ thermo-sensitive hydrogel depots for periodontitis treatment.

Lactobacillus acidophilus LA-5 Ameliorates Inflammation and Alveolar Bone Loss Promoted by A. actinomycetemcomitans and S. gordonii in Mice and Impacts Oral and Gut Microbiomes

The benefits of probiotics on dysbiotic microbiomes and inflammation are dependent on the tested strain, host factors, and the resident microbiome. There is limited knowledge on the effects of probiotics in A. actinomycetemcomitans-associated periodontitis. Thus, Lactobacillus acidophilus LA5 (LA5) was orally inoculated for 30 days in C57Bl/6 mice infected with A. actinomycetemcomitans JP2 (Aa) and S. gordonii (Sg). Alveolar bone loss, gingival gene expression, and oral and gut microbiomes were determined. LA5 controlled bone loss in Aa+Sg-infected mice, downregulated the expression of Il-1β and upregulated Il-10 in gingival tissues, and altered the oral and gut microbiomes. LA5 increased the diversity of the oral microbiome of Aa+Sg infected mice, and Aa+Sg and Aa+Sg+LA5 oral or gut microbiomes clustered apart. LA5 induced shifts in Aa+Sg infected mice by increasing the abundance of Muribaculaceae and decreasing Bifidobacteriaceae in the oral cavity and increasing the abundance of Verrucomicrobiae and Eggerthellales in the gut. In conclusion, LA5 oral administration controls experimental Aa-associated periodontitis by altering inflammatory gene expression and the oral and gut microbiomes.

J-shaped association between systemic immune-inflammation index and periodontitis: Results from NHANES 2009-2014

BACKGROUND

To examine the relationship between the systemic immune-inflammation index (SII) and periodontitis and to investigate possible effect modifiers.

METHODS

Data used in the present cross-sectional study are from the National Health and Nutrition Examination Survey (NHANES) 2009-2014 (N = 10,301). The SII was calculated using the following formula: (neutrophils count × platelet count)/lymphocytes count. The category of periodontitis was defined by the Centers for Disease Control and Prevention and American Academy of Periodontology (CDC/AAP) classification. We employed natural cubic spline and multivariable logistic regression analyses to evaluate the associations of the SII with periodontitis.

RESULTS

The associations between SII and periodontal health followed a J-shape (p < 0.001). The risk of periodontitis tended to reduce with the increment of log2(SII) in participants with log2(SII) ≤ 8.66 (odds radio [OR] = 0.83; 95% CI: 0.69-0.999), especially among non-Hispanic Whites (OR = 0.70; 95% CI: 0.52-0.95), and increased with the increment of log2(SII) in participants with log2(SII) > 8.66 (OR = 1.19; 95% CI: 1.02-1.38). A similar trend was also observed between the SII and the number of sites with probing pocket depth (PPD) ≥4 mm and clinical attachment loss (CAL) ≥ 3 or 5 mm. Furthermore, we found a significantly stronger correlation between lymphocytes and either neutrophils or platelets in individuals with log2(SII) > 8.66, as opposed to those with log2(SII) ≤ 8.66.

CONCLUSIONS

There is a J-shaped association between SII and periodontitis in US adults, with an inflection point of log2(SII) at 8.66, which may provide potential adjunctive treatment strategies for periodontitis with different immune response states. Further prospective trials are still required to confirm our findings.

The association between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) and prevalence of periodontitis among US adults: a cross-sectional NHANES study

The non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) is a recently developed lipid parameter, but there is currently a lack of research exploring its relationship with periodontitis. This study aims to identify the potential association between NHHR and periodontitis. The association between NHHR and periodontitis were examined through univariate and multivariate weighted logistic regression utilizing the National Health and Nutrition Examination Survey data from 2009 to 2014. The participants were grouped based on the type of periodontitis. This study included a total of 9023 participants, with 1947 individuals having no periodontitis, and an additional 7076 individuals suffering from periodontitis. Patients in periodontitis group demonstrated a statistically significant elevation in NHHR values 2.82 (2.05-3.80) compared to those in no periodontitis group (p < 0.001). Logistic regression analysis of variables demonstrated a positive association between NHHR and periodontitis [1.07 (1.02, 1.12) p = 0.0067]. The study revealed a positive association between NHHR and an elevated prevalence of periodontitis development. For each unit increase in NHHR, there is a 7% increase in the prevalence of periodontitis. Further investigations into NHHR may enhance our understanding of preventing and treating periodontitis. However, additional studies are required to validate these findings.

A novel macrolide-Del-1 axis to regenerate bone in old age

Aging is associated with increased susceptibility to chronic inflammatory bone loss disorders, such as periodontitis, in large part due to the impaired regenerative potential of aging tissues. DEL-1 exerts osteogenic activity and promotes bone regeneration. However, DEL-1 expression declines with age. Here we show that systemically administered macrolide antibiotics and a non-antibiotic erythromycin derivative, EM-523, restore DEL-1 expression in 18-month-old ("aged") mice while promoting regeneration of bone lost due to naturally occurring age-related periodontitis. These compounds failed to induce bone regeneration in age-matched DEL-1-deficient mice. Consequently, these drugs promoted DEL-1-dependent functions, including alkaline phosphatase activity and osteogenic gene expression in the periodontal tissue while inhibiting osteoclastogenesis, leading to net bone growth. Macrolide-treated aged mice exhibited increased skeletal bone mass, suggesting that this treatment may be pertinent to systemic bone loss disorders. In conclusion, we identified a macrolide-DEL-1 axis that can regenerate bone lost due to aging-related disease.

The Role of Interleukin 6 in Periodontitis and Its Complications

Interleukin 6 (IL-6) is a pleomorphic pro-inflammatory cytokine that is strongly associated with local as well as systemic inflammatory processes. Its role in physiological and pathogenic processes throughout the human body has been the subject of numerous studies in recent years. Measurements of the IL-6 levels in gingival crevicular fluid (GFC), as well as in serum, can be important diagnostic and prognostic factors in periodontal diseases (PD) and in assessing their impact on a range of related inflammatory diseases. This narrative review explores the significant role of IL-6 in patients with periodontitis and its association with other widespread inflammatory pathologies.

Complement C3 as a potential drug target in periodontitis: Evidence from the cis-Mendelian randomization approach

AIM

Evidence from a Phase IIa trial showed that a complement C3-targeted drug reduced gingival inflammation in patients with gingivitis. Using drug-target Mendelian randomization (MR), we investigated whether genetically proxied C3 inhibition alters the risk of periodontitis.

MATERIALS AND METHODS

We used multiple 'cis' instruments from the vicinity of the encoding loci of C3. Instrument selection was restricted to the drug target encoding loci (chromosome 19; 6,677,715-6,730,573 (GRCh37/hg19)). We selected three uncorrelated single-nucleotide polymorphisms (rs141552034, rs145406915, rs11569479) that were associated with serum C3 levels (p value <1 × 10-4 ) from a genome-wide association study (GWAS) of 5368 European descent individuals. We extracted association statistics from a GWAS of 17,353 clinical periodontitis cases and 28,210 European controls. Wald ratios were combined using inverse-variance weighted meta-analysis to estimate the odds ratio (OR) of the genetically proxied inhibition of C3 in relation to periodontitis.

RESULTS

MR analysis revealed that the inhibition of C3 reduces the odds of periodontitis (OR 0.91 per 1 standard deviation reduction in C3; 95% confidence interval 0.87-0.96, p value = .0003).

CONCLUSIONS

Findings from our MR analysis suggest a potential protective effect of C3 blockade against periodontitis.

Yunvjian decoction attenuates lipopolysaccharide-induced periodontitis by suppressing NFκB/NLRP3/IL-1β pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Yunvjian decoction (YNJ) is a traditional Chinese herbal prescription that has been used in the clinical treatment of periodontitis. However, the underlying molecular mechanism of YNJ in the periodontitis treatment is not well understood.

AIM OF THE STUDY

The purpose of this study was to evaluate the therapeutic effects of YNJ against periodontitis and its underlying molecular mechanisms.

MATERIALS AND METHODS

Orthodontic ligation and lipopolysaccharide (LPS)-induced periodontitis rat model was established. YNJ groups were gavaged with YNJ decoction (5 g/kg/d or 10 g/kg/d) for four months. The rats in positive control group were gavaged with metronidazole (MDZ, 100 mg/kg/d) for four months. The maxilla was scanned by micro-computed tomography. The chemical compositions of YNJ were identified using ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry. The molecular mechanism of YNJ were predicted using network pharmacological analysis and validated using immune-staining and Western blot.

RESULTS

YNJ treatment decreased the distance between cementoenamel junction and alveolar bone crest on the sagittal slide of the periodontitis rats. Western blot showed YNJ downregulated the protein levels of the bone resorption marker (receptor activator of nuclear factor-κB ligand), while upregulated the levels of the bone formation markers (bone morphogenetic protein 2, runt-related transcription factor 2, alkaline phosphatase, and osteoprotegerin) in alveolar bone of the periodontitis rats. Hematoxylin and eosin, immunohistochemical staining, and Western blot analysis indicated that YNJ attenuated the inflammation and decreased the levels of interleukin-6 and tumor necrosis factor-α in the alveolar bone. In addition, a total of 61 compounds were identified from YNJ. Network pharmacology indicated that the nucleotide binding oligomerization domain-like receptor signaling pathway was the main pathway for YNJ in the treatment of periodontitis. The experiments confirmed that YNJ administration inhibited LPS induced-pyroptosis in alveolar bone through suppressing the phosphorylation of nuclear factor κB, reduced expression of NOD-like receptor family pyrin domain containing 3, and Caspase-1, subsequently suppressing the interleukin-1β secretion.

CONCLUSION

YNJ is an effective therapeutic strategy for periodontitis and acts by inhibiting pyroptosis and NFκB/NLRP3/IL-1β pathway in alveolar bone.

New insights into nanotherapeutics for periodontitis: a triple concerto of antimicrobial activity, immunomodulation and periodontium regeneration

Periodontitis is a chronic inflammatory disease caused by the local microbiome and the host immune response, resulting in periodontal structure damage and even tooth loss. Scaling and root planning combined with antibiotics are the conventional means of nonsurgical treatment of periodontitis, but they are insufficient to fully heal periodontitis due to intractable bacterial attachment and drug resistance. Novel and effective therapeutic options in clinical drug therapy remain scarce. Nanotherapeutics achieve stable cell targeting, oral retention and smart release by great flexibility in changing the chemical composition or physical characteristics of nanoparticles. Meanwhile, the protectiveness and high surface area to volume ratio of nanoparticles enable high drug loading, ensuring a remarkable therapeutic efficacy. Currently, the combination of advanced nanoparticles and novel therapeutic strategies is the most active research area in periodontitis treatment. In this review, we first introduce the pathogenesis of periodontitis, and then summarize the state-of-the-art nanotherapeutic strategies based on the triple concerto of antibacterial activity, immunomodulation and periodontium regeneration, particularly focusing on the therapeutic mechanism and ingenious design of nanomedicines. Finally, the challenges and prospects of nano therapy for periodontitis are discussed from the perspective of current treatment problems and future development trends.

Enhancing osteogenic differentiation of MC3T3-E1 cells during inflammation using UPPE/β-TCP/TTC composites via the Wnt/β-catenin pathway

Periodontitis can lead to defects in the alveolar bone, thus increasing the demand for dependable biomaterials to repair these defects. This study aims to examine the pro-osteogenic and anti-bacterial properties of UPPE/β-TCP/TTC composites (composed of unsaturated polyphosphoester [UPPE], β-tricalcium phosphate [β-TCP], and tetracycline [TTC]) under an inflammatory condition. The morphology of MC3T3-E1 cells on the composite was examined using scanning electron microscopy. The toxicity of the composite to MC3T3-E1 cells was assessed using the Alamar-blue assay. The pro-osteogenic potential of the composite was assessed through ALP staining, ARS staining, RT-PCR, and WB. The antimicrobial properties of the composite were assessed using the zone inhibition assay. The results suggest that: (1) MC3T3-E1 cells exhibited stable adhesion to the surfaces of all four composite groups; (2) the UPPE/β-TCP/TTC composite demonstrated significantly lower toxicity to MC3T3-E1 cells; and (3) the UPPE/β-TCP/TTC composite had the most pronounced pro-osteogenic effect on MC3T3-E1 cells by activating the WNT/β-catenin pathway and displaying superior antibacterial properties. UPPE/β-TCP/TTC, as a biocomposite, has been shown to possess antibacterial properties and exhibit excellent potential in facilitating osteogenic differentiation of MC3T3-E1 cells.