Bioactive Glass Research Articles

Effect of a 1.1% NaF toothpaste containing Sr/F-doped bioactive glass on irradiated demineralized dentin: an in vitro study

Effect of a 1.1% NaF toothpaste containing Sr/F-doped bioactive glass on irradiated demineralized dentin: an in vitro study

Elevating alloy performance: the role of bioactive glass in Mg-9Al-Zn matrix composites through friction stir back extrusion

ABSTRACT This study investigates the impact of friction stir back extrusion (FSBE) parameters on the microstructure and mechanical properties of magnesium matrix composites reinforced with bioactive glass particles. Higher rotational speeds (1600 rpm) generate more heat and stirring, promoting finer grains and better particle dispersion, while lower speeds lead to larger grains. Conversely, slower extrusion speeds allow more time for heat dissipation and better mixing, contributing to smaller grains and a more uniform particle distribution. Key findings show that increasing the bioactive glass content enhances both hardness and ultimate tensile strength (UTS), with optimal mechanical properties achieved at 1600 rpm rotational speed, 48.97 mm/min extrusion speed, and 5 vol.% bioactive glass. The introduction of bioactive glass particles restricts grain growth and improves load transfer, thereby reinforcing the composite. Additionally, the study identifies a gradient microstructure in the composite wire, with smaller grains near the surface due to higher plastic strain and temperature, in contrast to the core, which exhibits larger grains.

Determining the Permeability of Porous Bioceramic Scaffolds: Significance, Overview of Current Methods and Challenges Ahead

The “architectural suitability” of scaffolds for bone tissue engineering is commonly evaluated by assessing the pore volume and the mean pore size (or pore size distribution, if possible) and comparing these values with the reference ranges of human cancellous bone. However, these two parameters cannot precisely describe the complex architecture of bone scaffolds and just provide a preliminary comparative criterion. Permeability is suggested as a more comprehensive and significant parameter to characterize scaffold architecture and mass transport capability, being also related to bone in-growth and, thus, functional properties. However, assessing the permeability of bioactive ceramics and glass scaffolds is a complex task from both methodological and experimental viewpoints. After providing an overview of the fundamentals about porosity in scaffolds, this review explores the different experimental and numerical approaches used to determine the permeability of porous bioceramics, describing the methodologies used (pump-based, gravity-based, acoustic and computational methods) and highlighting advantages and limitations to overcome (e.g., reliability issues and need for better standardization of the experimental procedures).

Bilayer Scaffolds Synergize Immunomodulation and Rejuvenation via Layer-Specific Release of CK2.1 and the "Exercise Hormone" Lac-Phe for Enhanced Osteochondral Regeneration.

Repairing osteochondral defects necessitates the intricate reestablishment of the microenvironment. The cartilage layer consists of a porous gelatin methacryloyl hydrogel (PGelMA) covalently crosslinked with the chondroinductive peptide CK2.1 via a "linker" acrylate-PEG-N-hydroxysuccinimide (AC-PEG-NHS). This layer is optimized for remodeling the senescent microenvironment in the cartilage region, thereby establishing a regenerative microenvironment that supports chondrogenesis. For the bone layer, silk fibroin methacryloyl (SilMA) is coated onto a three dimensional (3D)-printed 45S5 bioactive glass scaffold (BG scaffold). The "exercise hormone" N-lactoyl-phenylalanine (Lac-Phe) is loaded onto the SilMA, endowing it with diversified functions to regulate the osteogenic microenvironment. Systematic analysis in vitro reveals that PGelMA-CK2.1 shifts the microenvironment from a pro-inflammatory into an anti-inflammatory condition, and alleviates cellular senescence, thus modifying the cartilage microenvironment to improve the recruitment, proliferation and chondral differentiation of bone marrow mesenchymal stem cells (BMSCs). The scaffold bone layer enhances microvascular endothelial cell proliferation, migration, and angiogenic activities, which, couple with increased BMSC recruitment and regulatory mechanisms directing BMSC differentiation, favor a shift in the "osteogenesis-adipogenesis" balance toward enhanced osteogenesis. In vivo, it is found that this biphasic biomimetic scaffold favors simultaneous dual tissue regeneration. This approach facilitates the development of bioactive regenerative scaffolds and holds great potential for clinical application.

GelMA hydrogels reinforced by PCL@GelMA nanofibers and bioactive glass induce bone regeneration in critical size cranial defects.

The process of bone healing is complex and involves the participation of osteogenic stem cells, extracellular matrix, and angiogenesis. The advancement of bone regeneration materials provides a promising opportunity to tackle bone defects. This study introduces a composite hydrogel that can be injected and cured using UV light. Hydrogels comprise bioactive glass (BG) and PCL@GelMA coaxial nanofibers. The addition of BG and PCL@GelMA coaxial nanofibers improves the hydrogel's mechanical capabilities (353.22 ± 36.13kPa) and stability while decreasing its swelling (258.78 ± 17.56%) and hydration (72.07 ± 1.44%) characteristics. This hydrogel composite demonstrates exceptional biocompatibility and angiogenesis, enhances osteogenic development in bone marrow mesenchymal stem cells (BMSCs), and dramatically increases the expression of critical osteogenic markers such as ALP, RUNX2, and OPN. The composite hydrogel significantly improves bone regeneration (25.08 ± 1.08%) in non-healing calvaria defects and promotes the increased expression of both osteogenic marker (OPN) and angiogenic marker (CD31) in vivo. The expression of OPN and CD31 in the composite hydrogel was up to 5 and 1.87 times higher than that of the control group at 12 weeks. We successfully prepared a novel injectable composite hydrogel, and the design of the composite hydrogels shows significant potential for enhancing biocompatibility, angiogenesis, and improving osteogenic and angiogenic marker expression, and has a beneficial effect on producing an optimal microenvironment that promotes bone repair.

Enhancing the Biological Properties of Organic–Inorganic Hybrid Calcium Silicate Cements: An In Vitro Study

(1) Background: This study aimed to enhance the biological properties of hydraulic calcium silicate cements (HCSCs) by incorporating organic and inorganic components, specifically elastin-like polypeptides (ELPs) and bioactive glass (BAG). We focused on the effects of these composites on the viability, migration, and osteogenic differentiation of human periodontal ligament fibroblasts (hPDLFs). (2) Methods: Proroot MTA was supplemented with 1–5 wt% 63S BAG and 10 wt% ELP. The experimental groups contained various combinations of HSCS with ELP and BAG. Cell viability was assessed using an MTT assay, cell migration was evaluated using wound healing and transwell assays, and osteogenic activity was determined through Alizarin Red S staining and a gene expression analysis of osteogenic markers (ALP, RUNX-2, OCN, and Col1A2). (3) Results: The combination of ELP and BAG significantly enhanced the viability of hPDLFs with an optimal BAG concentration of 1–4%. Cell migration assays demonstrated faster migration rates in groups with 2–4% BAG and ELP incorporation. Osteogenic activity was the highest with 2–3% BAG incorporation with ELP, as evidenced by intense Alizarin Red S staining and the upregulation of osteogenic differentiation markers. (4) Conclusions: The incorporation of ELP (organic) and BAG (inorganic) into HCSC significantly enhances the viability, migration, and osteogenic differentiation of hPDLFs. These findings suggest that composite HCSC might support healing in destructed bone lesions in endodontics.

Chitosan-Modified Hydrogel Microsphere Encapsulating Zinc-Doped Bioactive Glasses for Spinal Cord Injury Repair by Suppressing Inflammation and Promoting Angiogenesis.

Spinal cord injury (SCI) is a common nerve injury caused by external force, resulting in sensory and motor impairments. Previous studies demonstrated that inhibiting the neuroinflammation promoted SCI repair. However, these approaches are low efficient, and lack targeting specificity, and even require repeated and high doses of systemic administration. To address such issues, in the present study, chitosan-modified hydrogel microspheres encapsulating with zinc-doped bioactive glasses (CS-MG@Zn/BGs) is constructed for targeted repair of SCI. In vitro, the CS-MG@Zn/BGs effectively inhibited the acute inflammatory response initiated by microglia and promoted angiogenic activities. In vivo, CS-MG@Zn/BGs targeted the injured site, and attenuated neuroinflammation by inhibiting microglia infiltration and modulating microglia polarization toward M2 type. Furthermore, it facilitated vascular reconstruction, neuronal differentiation, axonal regeneration and remyelination at the injured site, and thereby promoted motor function recovery of SCI mice. The in vitro and in vivo results implied that CS-MG@Zn/BGs may be a promising alternative for the rehabilitation of SCI.

Gelatin-Modified Bioactive Glass for Treatment of Dentin Hypersensitivity

When dentin is directly exposed to the oral cavity for various reasons, such as a lack of enamel on the tooth surface, external stimuli to the dentin often cause transient discomfort known as dentin hypersensitivity. In order to block the incoming stimulus signal, an ideal treatment is to induce the production of minerals to block the dentinal tubules. In this work, a dentin-desensitizing plugging material was prepared by modifying mesoporous bioactive glass with gelatin, the mineralization and desensitization effects of which were compared with Gluma in in vitro experiments. These experiments confirmed that gelatin-modified bioactive glass (MBG@PDA@Gel) is more effective than traditional desensitizing agents at blocking dentin tubules. Following the successful synthesis of MBG@PDA@Gel, as confirmed by scanning electron microscopy, transmission electron microscopy, and other tests, the treatment of demineralized dentin with MBG@PDA@Gel demonstrated that the dentinal tubules were tightly blocked under scanning electron microscopy. MBG@PDA@Gel induces minerals in deeper layers of dentinal tubules, promoting remineralization and forming a unified structure with the tubule blockage. Animal studies showed that MBG@PDA@Gel can remineralize demineralized dentin, and it is stable in the oral cavity and does not fall out. MBG@PDA@Gel not only enhances the biocompatibility of the nanoparticle but also results in an overall uniform and rapid remineralization of the demineralized dentin.

Fibrous‐biocomposites scaffold of natural rubber with bioactive glass–ceramic particles obtained by solution blowing spinning

AbstractBioactive glass‐ceramics (BGs) are widely used in clinical applications due to their excellent biodynamic and biological properties, though their low mechanical strength limits their use in load‐bearing contexts. This study aimed to develop fibrous biocomposite scaffolds based on natural rubber (NR) reinforced with BG particles, such as biosilicato (BioS) and 45S5‐K (BL0), to improve tensile strength, biocompatibility, and bioactivity for biomedical applications, such as tissue engineering. Morphological, tensile, thermal, and biological tests were conducted to evaluate the impact of BG particles on the NR fibrous matrix. TG/DTG analysis revealed similar decomposition profiles for NR/BioS and NR/BL0 biocomposites compared to NR mats, with primary degradation occurring in the 290–450°C range. Tensile tests demonstrated that the addition of 30 mass% BioS or BL0 enhanced the ultimate tensile strength (σbreak) of the NR matrix from 1.44 ± 0.08 to 3.38 ± 1.31 MPa (NR/BioS) and 1.97 ± 0.53 MPa (NR/BL0). The Cole–Cole plot indicated system heterogeneity and strong NR‐BG particle interactions. Cytotoxicity tests revealed over 70% MSC viability for NR, NR/BioS, and NR/BL0 biocomposites, meeting ISO 10993‐5:2009 standards. These findings suggest that incorporating BioS and BL0 enhances the mechanical and biological properties of NR‐based scaffolds, making them suitable for biomedical applications, such as bone regeneration.

Physio-Mechanic and Microscopic Analyses of Bioactive Glass-Based Resin Infiltrants.

This study aimed to investigate the efficacy and durability of bioactive glass-based dental resin infiltrants. Resin infiltrants were formulated by combining photoinitiated dimethacrylate monomers with three variations of bioactive glass: 45S5 Bioglass (RIS), boron-substituted (RIB), fluoride-substituted (RIF), and pure resins (PR), whereby TOOTH group (TH) and ICON (CN) served as commercial control groups. Teeth samples were prepared, and experimental and control infiltrants were applied on demineralized human-extracted teeth. All the samples were subjected to immersion in artificial saliva and pH cycling for 30 days. The samples from another group underwent tooth brushing simulation for 9600 cycles. Following artificial saliva immersion, the samples' hardness values showed that RIB had the highest values (318.44 ± 3.83) while PR (212.52 ± 9.02) had the lowest values. After immersing into the pH cycling solution, the RIF showed the highest hardness (286.86 ± 5.11), while the lowest values for the CN (143.76 ± 3.50). After the tooth brushing simulation, the teeth samples with RIB showed maximum microhardness values (312.06 ± 16.30) and the weakest for the TH (189.60 ± 6.43). The commercial and experimental enamel resin infiltrants showed almost similar results overall, with RIB demonstrating better microhardness and comparable surface roughness. In contrast, RIF proved more resistant to pH cycling, exhibited higher microhardness, and performed better in surface roughness analysis. These findings suggest that resin infiltrant materials, especially RIF, have promising potential for effectively and esthetically managing white spot lesions.

MBG/BSA Bone Grafts Immunomodulate Bone Regeneration by Releasing Bioactive Ions in Inflammatory Bone Defects.

Since the diseases that cause bone defects are mostly inflammatory diseases, the current bone grafts are unable to effectively regulate osteoimmune activity, leading to the impaired osteogenesis and unfavorable bone regeneration. In this study, inspired by bone composition, biomimetic mesoporous bioactive glass nanoparticle (MBG)/bovine serum albumin (BSA) bone grafts are designed for inflammatory bone defects. Systematically, MBG/BSA bone grafts are evaluated for characterization, bioactivity, anti-inflammatory, antioxidant activity, and osteogenic activity. MBG/BSA bone grafts are proved to be biocompatible and can release bioactive ions including calcium and silicon in a sustained manner. Furthermore, MBG/BSA reprograms the macrophage phenotype toward anti-inflammation that is beneficial for bone regeneration. The antioxidative activity is also validated under inflammation and the mechanism may be via the interleukin-4 (IL-4)/Signal transducer and activator of transcription 6 (STAT6)pathway. The osteogenic differentiation and mineralization are also facilitated due to the improved immunoregulation of MBG/BSA. Overall, this work suggests that the MBG/BSA bone grafts with improved immunomodulatory properties are an ideal material for inflammatory bone regeneration application.

Electrophoretic Deposition of Bioactive Glass 58S- xSi3N4 (0

This paper aims to investigate the biocompatibility, bioactivity and properties of bioactive glass 58S-xSi3N4 (0<x<20 wt.%) nanocomposite coating on AISI 316L stainless steel substrate, applied by electrophoretic deposition method. The implications of adding Si3N4 nanoparticles up to 20 wt.% to the bioactive glass coating for the structural and biomedical properties of deposited coatings were investigated. The deposited coating samples were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscope (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), and energy dispersive X-ray spectroscopy (EDS). For the evaluation of cellular toxicity, the MTT cytotoxicity test with MG63 bone cell was performed. Bioactivity test was also conducted in simulated body fluid (SBF) up to 28 days. Results showed that increase in the Si3N4 content of composite samples is associated with a significant decrease in the average size of composite powder, inferring that Si3N4 additive has become nucleation sites during synthesis. Stereomicroscope images showed that with an increase in deposition time up to 70 min, a uniform coating can be attained. An increase in the Si3N4 content is associated with a significant reduction in surface roughness and non-uniformities of the deposited layer. The addition of Si3N4 in the composite layer slightly increases the wetting angle. The highest cellular toxicity was observed for the AISI 316L sample at the concentration of 10 micromolar, while the lowest cellular toxicity is attributed to the BG-20%Si3N4 sample at the concentration of 75 micromolar, exhibiting viability values similar to the control sample. Bioactivity assessment of deposited coatings indicated a remarkable improvement in the bone-forming ability of Si3N4-containing bioactive glass composite.

Influence of the substitution of CaO by SrO on the structure, degradation and in vitro apatite formation of sol–gel derived SiO2–CaO–SrO–P2O5system bioactive glasses

The present study investigates the influence of the substitution of CaO by SrO on the structure, degradation and in vitro apatite formation of sol–gel-derived bioactive glasses with composition of 58SiO2–(38-x)CaO–xSrO–4P2O5, where x varies between 0 and 10 mol.%. The IV-type nitrogen adsorption/desorption isotherms and pore size values (ranging from 5.41 to 12.56 nm) confirmed the mesoporous structure of the synthesized glasses. The detailed structural analysis was carried out by X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). As network modifiers, the addition of Ca and Sr oxides disrupted the bonds of bridging oxygens (BOs) and resulted in the formation of non-bridging oxygens (NBOs), where the substitution of Ca with Sr led to an increase in Q1 units and a decrease in Q3 units. The effects of the addition of Sr on sample degradation and apatite formation were assessed using an assay in tris-(hydroxymethyl)-aminomethane and hydrochloric acid (Tris–HCl) and simulated body fluid (SBF). The results demonstrated that the substitution of CaO by SrO in the CaO–SiO2–P2O5 bioglass system altered the glass structure, resulting in reduced sample degradation and delayed apatite formation. This suggests that the incorporation of Sr into bioactive glasses may serve as a promising strategy to regulate the structure, dissolution behavior and apatite formation of silicate-based glasses, particularly concerning their long-term applications within the human body.

Alginate-gelatin based nanocomposite hydrogel scaffold incorporated with bioactive glass nanoparticles and fragmented nanofibers promote osteogenesis: From design to in vitro studies

The current study proposes fragmented nanofibers of polycaprolactone (FNF) with bioactive glass nanoparticles (nBG) incorporated into a polymeric matrix of alginate-gelatin for the creation of a hydrogel scaffold. Four groups were prepared: control, bioactive glass containing scaffold (BG), fragmented nanofibers with bioactive glass scaffold (FNF(PCL) + BG), and fragmented composite nanofibers scaffold (FNF (PCL + BG)). FNF (PCL + BG) scaffolds revealed a more controlled degradation rate, with approximately 20 % degradation occurring after 28 compared. The FNF(PCL) + BG scaffolds had the highest compressive strength in both dry and wet states. Following 14 days of incubation in simulated body fluid, hydroxyapatite formation had occurred on the surface of scaffolds containing nBG, and after 28 days on other groups tested. Cell studies revealed that the FNF(PCL) + BG scaffolds had superior cell viability without inhibiting cell proliferation. The FNF(PCL) + BG and FNF(PCL + BG) scaffolds had the highest alkaline phosphatase (ALP) activity and FNF(PCL) + BG scaffolds showed to support osteogenic differentiation.

Mimicking the Architecture and Dissolution Chemistry of Cancellous Bone Tissue to Optimize the Biocompatibility of Bioactive Scaffolds.

Synthesis of mechanically stable porous scaffolds with an architecture analogous to cancellous bone tissue poses significant challenges to bioactive glass (BG) based scaffolds. This is primarily due to densification and crystallization of the BG's during heat treatment. This study presents a modified BG series (42SiO2-xTiO2-24Na2O-21CaO-13P2O5, where x = 8 and 16 TiO2). TiO2 replaced the SiO2 concentration in the glass and was incorporated due to its biocompatibility and influence on glass structure. Material characterization determined that TiO2 did not induce crystallization within the glass but did increase the glass transition temperature (Tg) from 520°C to 600°C thereby indicating a more stable network connectivity. Scaffolds were synthesized using the foam replication method, resulting in scaffolds with a pore size of approximately 500 μm with the BG-4 composition (30SiO2-12TiO2-24Na2O-21CaO-13P2O5) retaining its amorphous character post-heat treatment. Scaffold ion release was monitored over 5-60 days in simulated body fluid (SBF). Si4+ release was found to decrease, while Ca2+ levels increased in SBF as TiO2 replaced SiO2 within the glass series. Cytocompatibility studies revealed that MC3T3 Osteoblast cells proliferated on the BG-4 scaffold surface and at its interface within culture media, and cell numbers were not significantly reduced.

Multifunctional scaffolds of β-tricalcium phosphate/bioactive glass coated with zinc oxide and copper oxide nanoparticles

Incorporating nanoparticles into scaffolds with regenerative potential is a promissory strategy to provide them with antimicrobial activity. Bioceramics, such as β-tricalcium phosphate (β-TCP) and bioactive glasses (BGs), stand out among synthetic materials for bone regeneration. In this context, we report the incorporation of zinc oxide (ZnO) and copper oxide/copper nitrate (CuO/Cu2H3NO5) nanoparticles onto the surface of the β-TCP/BG scaffolds. This report addresses the physicochemical characterization of the scaffolds, their antimicrobial activity, and their response to MC3T3-E1 cells. Our findings show that the incorporation of both nanoparticles effectively inhibited S. aureus growth, including its biofilm formation. While the presence of the nanoparticles initially decreased MC3T3-E1 cell viability, cell proliferation improved with prolonged incubation. Overall, the β-TCP/BG_Zn and β-TCP/BG_Cu scaffolds showed an early antimicrobial response, aiding infection eradication, while also supporting cell proliferation over time.

Assessment of the bioactivities of spray-dried pure and Zn-containing bioactive glass by experimental and DFT analysis

Assessment of the bioactivities of spray-dried pure and Zn-containing bioactive glass by experimental and DFT analysis

Electrophoretic deposition of curcumin-loaded mesoporous bioactive glass nanoparticle-chitosan composite coatings on titanium for treating tumor-induced bone defect

Clinical treatment of osteosarcoma (OS) presents significant challenges in postoperative tumor recurrence and large segmental bone defects, often necessitating joint replacement or artificial bone implantation to repair failed or defective bone tissue. At the same time, fibroblastic encapsulation can impede direct contact between implants and bones, leading to implant failure. To tackle these issues, mesoporous bioactive glass nanoparticles (MBN) were synthesized and then loaded with curcumin (CUR). Subsequently, chitosan (CTS) was chosen as the charger and coating matrix, and electrophoretic deposition (EPD) was utilized to fabricate a CTS-MBN-CUR composite coating with triple functionality on Ti implants aiming for OS-induced bone repair. MBN-CUR nanoparticles are encapsulated in CTS and uniformly distributed within the coating, achieving robust adhesion and long-term release of CUR. Concurrently, the developed CTS-MBN-CUR coating exhibits moderate hydrophilicity, and good bioactivity. Moreover, three different types of cells, MC3T3-E1, L929, and MG63 cells, were individually cultured with the composite coating and subjected to comprehensive cellular studies. The coating presented favorable bioactivities, and osteogenic performance, and the ability to resist the activity of fibroblast and OS cells. These findings suggest that CTS-MBN-CUR holds promising potential for bone regeneration following OS resection surgery.

In vitro assessment of the anti-biofilm effectiveness of copper and zinc enhanced borate bioactive glass using processed microscopic images

In vitro assessment of the anti-biofilm effectiveness of copper and zinc enhanced borate bioactive glass using processed microscopic images

Case-control Study: Comparative Evaluation of Bio active Glass (Novabone Putty) and Demineralized Freeze-dried Bone Allograft in the Treatment of Mandibular Furcation Defects.

The aim of this study was to compare a second-generation bioactive glass putty biomaterial (Novabone putty) against demineralized freeze-dried bone allograft (DFDBA) in mandibular grade II furcation defects. Fifteen systematically healthy individuals in the age range of 38-50 years were selected for this split-mouth study. Group I consisting of 15 sites, was treated with DFDBA and group II consisting of 15 sites was treated with Novabone putty (NB putty). The clinical parameters recorded at 0, 3 and 6 months included plaque index (PI), gingival index (GI), probing pocket depth (PPD), relative vertical attachment level (RVAL) and relative horizontal attachment level (RHAL). Standardized intraoral periapical radiographs were taken at all 30 sites pre-and 6 months post-operatively. Probing pocket depth reduced significantly (p = 0.001) when baseline values were compared to 3 and 6 months postoperatively. In group II mean RVAL changed from 6.56 ± 1.44 at baseline to 4.80 ± 1.14 at 3 months and 4.80 ± 1.33 at 6 months which was found to be highly significant (HS) (p = 0.001). The mean RHAL also showed a significant difference when baseline values were compared to 6 months post-operatively in both the groups. With respect to defect depth and bone density, no significant difference was found between the two groups. Significant improvement of the clinical parameters were seen in both the groups. As both the groups showed increase in defect fill and bone density, it can be summarized that NB putty seems to have comparable regeneration property to that of DFDBA when used for mandibular grade II furcation defects. The ease of use and higher level of biological performance of second-generation bioactive glass putty make it an ideal graft material. How to cite this article: Sen A, Rajan P, Kumar V, et al. Case-control Study: Comparative Evaluation of Bio active Glass (Novabone Putty) and Demineralized Freeze-dried Bone Allograft in the Treatment of Mandibular Furcation Defects. J Contemp Dent Pract 2024;25(7):696-702.