Search Results (387)

Background/Objectives: Periodontitis is characterized by the gradual breakdown of tooth-supporting tissues, including the periodontal ligament and alveolar bone, while current regenerative strategies remain limited. Palm mixed-carotenes (PMC), a natural carotenoid-rich compound with antioxidant and cytoprotective properties, may have potential in periodontal regenerative research. However, its effects on human periodontal ligament stem cells (hPDLSCs) remain underexplored. This study evaluated the effects of PMC on hPDLSC viability, wound closure, and osteogenic- and bone remodeling-related molecular responses. Methods: Primary hPDLSCs were isolated, characterized, and treated with PMC at concentrations ranging from 0 to 100 μg/mL. Cell viability was evaluated using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, wound closure using a wound-scratch assay, gene expression of osteoprotegerin (OPG), osteopontin (OPN), and osteocalcin (OCN) using real-time polymerase chain reaction (RT-qPCR), and secreted protein levels using enzyme-linked immunosorbent assay (ELISA). Results: PMC showed a biphasic viability response, with 6.25 μg/mL producing the most favorable effect by increasing the cell viability to 111.6% relative to the negative control. This concentration was selected, together with 12.5 μg/mL, for subsequent assays. In the wound-scratch assay, 6.25 μg/mL PMC significantly enhanced wound closure at 48 and 72 h, reaching 75.17% at 72 h compared with 52.69% in the negative control. Gene expression analysis showed that 6.25 μg/mL PMC significantly upregulated OPG mRNA expression compared with the negative control, 12.5 μg/mL PMC, and positive control groups. OPN and OCN showed limited responses, and PMC did not significantly increase secreted OPG or OCN protein levels. Conclusions: Overall, PMC at 6.25 μg/mL demonstrated the most favorable response in hPDLSCs, suggesting its potential as a bioactive candidate for further periodontal regenerative research. Full article

Mechanical loading of connective tissues is traditionally prescribed by force magnitude. In viscoelastic tissues, a constant external force does not produce a constant internal mechanical environment: stress and strain evolve continuously after load onset, creating a time-varying tissue-level mechanical history relevant to resident cells. This distinction is rarely accounted for in clinical loading protocols or scaffold design. The rate of evolution is governed by the stress relaxation time constant (τ). How τ controls the persistence of mechanical signals under force-controlled sustained loading remains poorly quantified. Thus, we developed a three-dimensional finite element model of the Wistar rat maxillary first molar tooth–periodontal ligament (PDL)–bone complex with a PDL geometry reconstructed from micro-CT imaging by original frame-by-frame manual segmentation and compared outcomes across three τ values spanning two orders of magnitude under identical 0.5 N sustained loading. Under the same applied force, stress retention at 100 s ranged from 68% to 97%, while concurrent deformation creep showed an inverse relationship. These results demonstrate that τ strongly governs the persistence of mechanical signals under sustained force-controlled loading in this model. Supplementary simulations under oblique loading and perturbed PDL modulus confirmed that τ remains the dominant constitutive determinant of stress retention across altered loading directions and stiffness conditions. Full article

Periodontal and alveolar bone regeneration requires coordinated angiogenic and osteogenic responses supported by biomimetic scaffolds. This study compared three-dimensional bioprinted hydroxyapatite–acrylated palm olein (3D-HA–APO) scaffold formulations containing 5%, 7% and 10% (w/v) hydroxyapatite (HA), designated F1, F2 and F3, respectively. Human umbilical vein endothelial cells were cultured on the scaffolds, and background-corrected soluble vascular endothelial growth factor (VEGF) concentrations in culture supernatants were quantified by enzyme-linked immunosorbent assay (ELISA). Angiogenic-related responses of human periodontal ligament stem cells were assessed by VEGF and cluster of differentiation 31 (CD31) immunofluorescence after endothelial induction, while alkaline phosphatase (ALP) activity in construct lysates was used as an indicator of early osteogenic activity. Soluble VEGF concentrations increased from F1 to F3, with significant differences between all formulations. VEGF-associated signal proportions differed among formulations, with F3 significantly higher than F1. CD31-associated signal proportions increased progressively from F1 to F3, with significant differences between all formulation pairs. ALP activity increased over time in all scaffold groups, and F3 generally showed the highest activity from Day 4 onwards. Overall, F3 showed the most favourable formulation-level profile across the selected angiogenic-related and early osteogenic outcomes. Full article

Periodontal organoid research remains underdeveloped, largely due to the lack of standardized fabrication protocols and multicellular constructs capable of reproducing epithelial–mesenchymal interactions relevant to periodontal biology. In particular, it remains unclear whether different spatial assembly strategies influence construct stability, multicellular organization, or early molecular behavior in periodontal three-dimensional (3D) systems. Therefore, this study aimed to develop and compare two different methods for generating dual-lineage 3D periodontal organoid-like constructs using human periodontal ligament cells (hPDL) and human gingival epithelial cells (hGEP). These strategies were selected to compare two biologically and technically distinct spatial configurations: bilayer assembly to partially mimic epithelial–connective tissue compartmentalization, and surface seeding as a simplified fabrication approach with potential advantages for reproducibility and workflow standardization. Both cell types were cultured in different media conditions (CnT-57, DMEM, and a 1:1 CnT-57/DMEM mixture) to determine compatibility for co-culture applications. Cell viability was assessed on days 1, 3, and 7 using the MTS assay. Constructs were produced in hyaluronic acid-based hydrogels using two strategies: Group 1–sequential photopolymerization of hPDL and hGEP layers to generate a bilayer construct; and Group 2—encapsulation of hPDL followed by direct seeding of hGEP onto the construct surface. Viability within constructs was evaluated on days 3 and 7 using the Live/Dead assay. Morphology was monitored using stereomicroscopy on days 0, 1, 3, and 7. Exploratory RNA sequencing was performed on day 7 to characterize transcriptomic profiles. All tested culture media maintained cellular viabilities above 70%, with no statistically significant differences among conditions (p > 0.05), indicating biocompatibility for both cell types. Group 1 exhibited viabilities of 86.54% ± 8.55% and 90.69% ± 7.88% on days 3 and 7, respectively, while Group 2 showed viabilities of 87.00% ± 9.58% and 88.08% ± 9.12%, with no significant intergroup differences (p > 0.05). Morphological analyses demonstrated preservation of construct integrity and progressive interaction between epithelial and mesenchymal compartments. Exploratory RNA sequencing revealed only subtle transcriptomic differences between assembly strategies. In conclusion, both methodologies successfully generated viable and structurally stable dual-lineage periodontal organoid-like constructs within a hyaluronic acid-based matrix. Comparison of these two assembly strategies demonstrates the feasibility of generating reproducible multicellular periodontal 3D models using distinct spatial configurations, establishing a proof-of-concept platform for future optimization toward periodontal disease modeling, regenerative studies, and advanced biofabrication applications. Full article

Calcium silicate-based repair materials are widely used in endodontics, and bioinspired polymeric biomodification may influence their cellular response. However, the cytotoxicity profile of mineral trioxide aggregate (MTA) modified with Octenisept^® or with an acetic acid-based chitosan vehicle has not been specifically evaluated in a controlled design comparing chitosan-modified MTA groups under parallel MTA extract and direct solution exposure conditions, although biomodifier effects may differ when tested alone and when incorporated into an MTA matrix. This in vitro study evaluated the MTT-based cytotoxicity profile of MTA subjected to bioinspired chitosan-based biomodification in human periodontal ligament fibroblasts (hPDLFs), using Octenisept^® as an antiseptic comparator biomodifier and 1% acetic acid as the vehicle control. Extracts of unmodified-MTA, MTA + 1% acetic acid, MTA + 1% chitosan, MTA + 3% chitosan and MTA + Octenisept^® were tested at 100%, 50% and 25% concentrations. The corresponding solutions were tested under direct exposure at 100%, 50%, 25% and 12.5%. Cell viability was assessed after 24 and 72 h using the MTT assay, and values below 70% were considered cytotoxic according to ISO 10993-5. Direct solution exposure produced stronger cytotoxicity, particularly for Octenisept^®. Among the MTA extract groups, only MTA + 1% chitosan maintained non-cytotoxic cell viability at 72 h under undiluted extract conditions. Full article

Periodontitis, a chronic inflammatory disease driven by plaque biofilm, is a leading cause of tooth loss in adults worldwide. Effective treatment requires not only infection and inflammation control but, more critically, functional regeneration of the periodontal ligament, cementum, and alveolar bone. Periodontal regeneration, however, is a highly ordered, multi-stage biological cascade involving temporally coordinated phases of blood clot formation, inflammatory regulation, tissue formation, and remodeling. Conventional single-drug or mixed-delivery strategies cannot distinguish the distinct demands of each healing phase and fail to replicate this natural rhythm. Sequential controlled-release systems address this gap by delivering multiple bioactive agents (antimicrobials, immunomodulators, and growth factors) in a programmed order tailored to the healing cascade, enabling precise modulation of the periodontal microenvironment and orderly tissue regeneration. This review systematically summarizes advances in these systems, classifying material platforms into four categories: (1) diffusion-barrier and degradation-kinetics systems, including multilayer films, core–shell fibers, porous microspheres, and microneedle arrays; (2) stimuli-responsive systems triggered by pH, matrix metalloproteinases, reactive oxygen species, or exogenous physical stimuli; (3) cell and extracellular vesicle-based systems exploiting the inflammatory tropism of M2 macrophage-derived exosomes for targeted immune reprogramming; and (4) asymmetric structural designs achieving spatiotemporal coordination of physical and biochemical signals through hierarchical architectures. These systems follow an anti-infection/anti-inflammation first, osteogenesis later therapeutic logic, circumventing temporal antagonism among bioactive factors. However, significant challenges hinder clinical translation, including individualized prediction of release kinetics, long-term biocompatibility of carrier materials, material retention under dynamic oral conditions, translational limitations of animal models, and precise regulation of complex factor networks. Future progress will likely depend on multi-responsive and logic-gated systems, deeper integration of biotechnology and immunomodulation, personalized precision medicine, AI-driven material design, and robust clinical translational research. Full article

Periodontitis is a chronic inflammatory disease characterised by progressive destruction of the periodontal tissues and alveolar bone. Cyclooxygenase-2 (COX-2) plays a key role in the pathogenesis of inflammatory responses via prostaglandin E₂ (PGE₂) receptors (EP1–4). Non-invasive physical plasma (NIPP) has been shown to modulate cellular activity and exert antimicrobial and anti-inflammatory effects. The aim of this in vitro study was to investigate the impact of NIPP on inflammation- and apoptosis-related molecules, including COX-2, EP2-EP4, Interleukin (IL)-6, IL-8, apoptotic protease activating factor 1 (APAF-1), Caspase (CASP)-3, and CASP-9, IL-10 and B-cell lymphoma 2 (BCL2) in human periodontal ligament cells (hPDLC) under normal and inflammatory conditions. After exposure of hPDLC to IL-1β to mimic inflammation in vitro, cells were treated with NIPP. Gene expression was analysed 24 h post-treatment by quantitative RT-PCR. Protein levels were assessed by ELISA. NIPP significantly inhibited IL-1β-induced upregulation of COX-2, EP2 and EP4 receptors, and APAF-1 mRNA expression in hPDLCs after 24 h. At the protein level, IL-1β-induced expression of COX-2, IL-6 and IL-8 was effectively attenuated by NIPP treatment. In conclusion, our data suggest that NIPP may modulate inflammatory responses in hPDLC, indicating its potential as a promising adjunctive approach for the treatment of periodontitis. Full article

Material selection is crucial to hard tissue regeneration, and matching scaffold properties to those of the target tissue can improve clinical outcomes. This study compared the physicochemical, mechanical, and biological performance of fibrous scaffolds fabricated from polycaprolactone (PCL), polydioxanone (PDO), and gelatin methacryloyl (GelMA) for hard tissue regeneration. Polymeric fibers were produced by electrospinning, and their morphological, physical, and mechanical properties were characterized by scanning electron microscopy (SEM, n = 2), swelling and degradation analyses (n = 8), water contact angle measurements (n = 16), and tensile testing (n = 8). In addition, periodontal ligament stem cells (PDLSCs), alveolar bone marrow stem cells (aBMSCs), and dental pulp stem cells (DPSCs) were seeded onto the scaffolds to evaluate cell spreading (n = 4), viability (n = 8), and mineralized matrix formation (n = 6). Data were analyzed using one- or two-way ANOVA followed by appropriate post hoc tests (α = 5%). All polymers formed homogeneous fibrous scaffolds, with diameters within the nanoscale range. PDO and GelMA showed higher swelling than PCL, while PCL retained approximately 95% of its initial mass after three months. PCL and PDO showed higher elongation at break, tensile strength, and Young’s modulus than GelMA. Both PDO and GelMA displayed contact angles below 90°, with GelMA showing the lowest values. In vitro, all polymers were cytocompatible: PDO and GelMA enhanced DPSC viability at 7 days, whereas GelMA produced the highest viability for PDLSCs and aBMSCs at that time point. GelMA also promoted the highest mineralized matrix formation for DPSCs and PDLSCs, with no significant differences among polymers for aBMSCs. Overall, GelMA scaffolds promoted greater cell viability and mineralized matrix formation, while PCL and PDO provided superior mechanical properties, highlighting the importance of balancing biological and mechanical requirements when designing scaffolds for hard tissue regeneration. Full article

Glucagon-like peptide-1 receptor agonists (GLP-1RAs), widely used in the management of type 2 diabetes mellitus and obesity, have recently attracted attention for their potential effects on periodontal tissues. This systematic review aimed to evaluate the current evidence regarding the relationship between GLP-1-based therapies and periodontal health, with particular emphasis on anti-inflammatory, osteogenic, and regenerative mechanisms. A comprehensive literature search of PubMed, Web of Science, and Embase databases identified 22 eligible studies, including in vitro, animal, and human investigations. The available evidence suggests that GLP-1RAs such as liraglutide and exendin-4 may attenuate periodontal inflammation, reduce alveolar bone loss, and enhance osteogenic differentiation of periodontal ligament and dental pulp stem cells through modulation of pathways including MAPK/ERK, Wnt/β-catenin, NF-κB, and PKCβ2. Clinical observations additionally indicate a bidirectional relationship between periodontitis and incretin signalling, with periodontal therapy associated with increased systemic GLP-1 levels. However, the current evidence remains heterogeneous and is largely limited to preclinical and observational studies. Randomised clinical trials are required to determine the clinical efficacy and therapeutic relevance of GLP-1-based therapies in periodontitis management. Full article

Objectives: This scoping review summarized the evidence on the biocompatibility of pit and fissure sealants, focusing on cytotoxicity, genotoxicity, and overall biological safety of commercial and experimental materials evaluated in vitro and in vivo. Methods: Following the PRISMA-ScR guidelines, eligibility was defined using the Population, Concept, and Context (PCC) framework: the population comprised cell cultures, animal models, or human participants exposed to sealants; the concept was biocompatibility, including cytotoxicity, genotoxicity, and inflammatory or tissue response; and the context encompassed commercial and experimental pit and fissure sealants used in preventive dentistry, particularly in pediatric populations. PubMed and Scopus platforms were searched without restrictions on publication year or language. Studies assessing biocompatibility (cytotoxicity, genotoxicity, inflammatory or tissue response) in cell cultures, animal models, or humans were eligible; those evaluating only clinical efficacy were excluded. Two reviewers independently performed study selection and data extraction. Results: Of 406 records (291 after deduplication), 10 studies were included—nine in vitro and one in vivo. Resin-based sealants predominated, mainly assessing residual monomers (TEGDMA, Bis-GMA) and their effects on fibroblasts, keratinocytes, periodontal ligament cells, and buccal epithelial cells. TEGDMA was released most frequently, whereas Bis-GMA showed the highest cytotoxicity. Experimental sealants containing nano-calcium fluoride, calcium phosphate, bioactive glass, or antibacterial monomers generally showed favorable biocompatibility, although high additive concentrations reduced cell viability. The single in vivo study reported good biocompatibility without significant genotoxicity. Conclusions: Pit and fissure sealants generally show acceptable biocompatibility and remain safe for caries prevention, although the biological response depends on composition, degree of polymerization, and residual monomer release. Further standardized long-term in vivo research is needed, particularly in pediatric populations. Full article

Background: Tooth root caries and periodontal tissue loss remain major challenges in elderly and periodontally compromised patients, while current restorative materials lack combined antibacterial and regenerative properties. Objective: The objective of this study was to develop a novel metformin-containing antibacterial composite for root cavity restorations to prevent recurrent caries and potentially promote periodontal tissue regeneration. Methods: Experimental composites contained 5% dimethylaminohexadecyl methacrylate (DMAHDM), varying metformin concentrations (2.5–15%), and glass fillers. Mechanical and antibacterial properties as well as cytocompatibility toward human periodontal ligament stem cells (hPDLSCs) were investigated. Results: The experimental composites achieved flexural strengths of 67.9 to 50.1 MPa (n = 6), significantly higher than (41.3 ± 3.4 MPa) of commercial control Vitremer (p < 0.05), while maintaining clinically acceptable elastic moduli of 3.7–3.1 GPa. Experimental composites achieved an 8-log reduction in Streptococcus mutans (S. mutans) biofilms and significantly reduced lactic acid production and metabolic activity compared to biofilms on commercial controls. The composite containing 15% metformin demonstrated acceptable cytocompatibility toward hPDLSCs under clinically relevant diluted conditions, matching commercial controls (p > 0.1). Conclusions: These findings suggest that this novel composite possesses potent antibacterial activity, acceptable cytocompatibility, and adequate mechanical properties, making it promising for multifunctional root caries restorations. Full article

Ectopic olfactory receptors (ORs) are G protein-coupled chemosensors expressed outside the olfactory epithelium, where they may couple local chemical inputs to cell-specific signaling. The oral cavity is continuously exposed to food-derived compounds, microbial metabolites, volatile organic compounds, and inflammation-associated metabolites, yet the molecular roles of oral ORs remain incompletely defined. This review critically synthesizes current evidence for OR expression and signaling in oral tissues and associated cell populations, with emphasis on ligand–receptor–signaling relationships and disease relevance. Functional OR signaling has been demonstrated in mammalian taste cells, while emerging transcriptomic studies in oral mucosa and transcriptomic/localization studies in the periodontal ligament indicate OR-related programs during tissue-specific or repair-associated states. Candidate metabolic axes, including short-chain fatty acids and lactate linked to OR51E1/OR51E2/Olfr78-related pathways in non-oral models, provide testable mechanistic hypotheses for microbiome–host communication in periodontitis and oral cancer; however, direct causal validation in oral disease models remains limited. We propose an evidence-tiered framework integrating spatial expression mapping, metabolomics-guided deorphanization, receptor perturbation, and longitudinal oral-fluid profiling. Oral ORs should currently be regarded as candidate molecular modulators and components of multimodal biomarker strategies rather than validated standalone diagnostic or therapeutic targets. Full article

Background: Artemisia absinthium (A. absinthium) is a perennial plant valued for its antibacterial, antioxidant, and anti-inflammatory properties, exhibiting broader therapeutic potential. Given the need to deliver low doses of A. absinthium extract, mesoporous silica nanoparticles have attracted considerable attention as promising nanocarriers due to their distinctive physical and chemical properties. Methods: Physicochemical characterization of the materials was performed and biological assays were conducted to investigate the ROS, antibacterial and antioxidant activity of A. absinthium extract encapsulated within cerium- and calcium-doped mesoporous silica nanoparticles (MNSiCaCe) against both aerobic and anaerobic bacteria. Results: FTIR, SEM, and BET analysis confirmed successful synthesis of the MNSiCaCe. Phytochemical profiling of Artemisia absinthium extract using HPLC revealed the presence of artemisinin and a rich composition of phenolic and flavonoid constituents, with a total phenolic content of 182 ± 3.6 mg GAE/100 g dry plant material and a total flavonoid content of 42.5 ± 0.6 mg QE/100 g. Quantitative drug loading profiling demonstrated that while plain MNSi nanocarriers achieved a loading capacity of 16.96%, the MNSiCaCe enhanced this threshold to 43.11%. The in vitro controlled-release kinetics exhibited a highly prolonged and slow-release profile of the MNSiCaCe. The materials demonstrated excellent hemocompatibility and high mitochondrial activity with human periodontal ligament cells (hPDLCs). Elevated ROS generation was observed under conditions where antibacterial activity was most pronounced. While the artemisinin-doped nanoparticles showed notable antibacterial effects, the complete Artemisia absinthium-loaded nanoparticles achieved a significantly greater reduction in bacterial viability probably due to the synergistic interaction between artemisinin and the extract’s rich polyphenol profile. Conclusions: These findings highlight MNSiCaCe as a promising and safe nanocarrier system for drug delivery, with strong antibacterial potential, offering valuable applications in antibacterial therapies. Full article

Periodontitis is a chronic inflammatory disease driven largely by dysregulated host responses that lead to destruction of periodontal tissues. Integrins are heterodimeric transmembrane receptors that regulate cell adhesion and bidirectional signaling in epithelial cells, immune cells, periodontal ligament fibroblasts, and osteoclasts. During disease progression, integrin-related responses may shift across overlapping molecular phases. Epithelial integrins such as α3β1 and α6β4 support barrier integrity, whereas α5β1 may facilitate microbial interaction and inflammatory signaling. β2 integrins and α4β1 contribute to leukocyte recruitment and inflammatory amplification, whereas increased α9β1-associated signaling and reduced αvβ6-mediated regulation of transforming growth factor β (TGF-β) may promote inflammatory persistence. Matrix-associated integrins, including α2β1 and α11β1, support extracellular matrix (ECM) organization and mechanotransduction, whereas αvβ3 cooperates with Receptor activator of nuclear factor kappa B ligand (RANKL) to promote osteoclast activity and alveolar bone resorption. Impaired β1 integrin-dependent signaling and potentially reduced αvβ5-associated efferocytosis may contribute to defective resolution and regeneration. Importantly, integrin expression, activation, and downstream signaling are distinct, and the strength of evidence varies among integrin subtypes. This review proposes a conceptual framework in which periodontitis reflects a dynamic imbalance in integrin-mediated processes that link inflammation, bone resorption, and regenerative failure, rather than being a direct equivalent of clinical periodontal stages or grades. Full article

Background/Objectives: Autophagy is a key degradative pathway involved in orthodontic tooth movement. DNA damage-regulated autophagy modulator 1 (DRAM1), a protein that plays a central role in the degradation of autophagic cargo, exhibits differential regulation in human periodontal ligament (hPDL) fibroblasts under compressive force. Single-nucleotide polymorphisms (SNPs) may influence force-induced gene expression. Therefore, this study investigated the impact of DRAM1 SNPs on its expression in hPDL fibroblasts under compression force. Methods: The hPDL sample comprised cells of 59 patients. A physiological compressive strain of 2 g/cm³ was used to simulate orthodontic tooth movement. Total RNA from hPDL fibroblasts was isolated to determine DRAM1 relative gene expression under loaded conditions and in a physiological control. Furthermore, a genotyping analysis of six SNPs within the DRAM1 gene (rs756534 (G/T), rs2138257 (C/T), rs2176092 (C/T), rs4622329 (A/G), rs10860812 (A/G), and rs4764657 (A/G)) was performed using real-time polymerase chain reaction. DRAM1 expression was com-pared among genotypes of each SNP using an alpha of 5%. Linear regression analysis was then employed to evaluate SNP-SNP interaction. Results: The relative DRAM1 gene expression was not statistically significantly different (p > 0.05) according to the geno-types. The SNP-SNP interaction did not demonstrate any statistically significant associ-ation either. Conclusions: DRAM1 gene expression in hPDL fibroblasts under orthodontic compression may not be regulated by the studied intronic SNPs in the gene encoding DRAM1. Full article