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Phosphate-based glasses (PBGs) in the CaO–Na2O–P2O5 system have diverse applications as biomaterials due to their unique dissolution properties. A reactive force field (ReaxFF) has been developed to simulate these materials at the atomic level. The ReaxFF parameters of PBGs, including the interaction between phosphorus and calcium atoms, have been developed using a published code based on genetic algorithms. The training data, including the atomic charges, atomic forces, bond and angle parameters, and different differential energies, are chosen and measured from static quantum-mechanical calculations and ab initio molecular dynamics of PBGs. We did different short- and medium-range structural analyses on the bulk simulated PBGs with different compositions to validate the developed potential. Radial and angular distribution functions and coordination numbers of network formers and modifiers, as well as the network connectivity of the glass, are in agreement with experimental and previous simulations using both shell-model classical force fields and ab initio simulated data; for example, the coordination number of phosphorus is 4.0. This successful development of ReaxFF parameters being able to describe the bulk PBGs enables us to work on the dissolution behavior of the glasses, including the interaction of water molecules with PBGs, in future works. [ABSTRACT FROM AUTHOR]

Borate bioactive glasses (BGs) have become indispensable in biomedicine for their exceptional bioactivity and tunable degradation characteristics. This study presents the synthesis and comprehensive evaluation of BGs within the x B 2 O 3 -CaO-Na 2 O-K 2 O-MgO-P 2 O 5 system, featuring varying compositions of B 2 O 3 (x = 40, 55, and 70 mol.%), using both sol-gel and melting techniques. A systematic investigation of their structural evolution, degradation kinetics, apatite-forming capabilities, and cytotoxicity has been conducted. The results demonstrate that the borate BGs with elevated B 2 O 3 content significantly accelerates the degradation rate and enhances bioactivity across both synthesis methods, as B 2 O 3 content increases from 40 to 70 mol%. Notably, the sol-gel derived BG samples demonstrate pronounced degradation, with mass loss reaching up to 90 %, and superior hydroxyapatite formation in simulated body fluid, surpassing the performance of their melting-derived counterparts. Cytotoxicity assays with MC3T3-E1 cells reveal no significant inhibitory effects from any of the borate bioglasses. Moreover, ab initio molecular dynamics simulations have been utilized to elucidate the relationship between structural alterations and in vitro bioactivity, with a particular emphasis on the boron coordination number. These findings provide a promising strategy for the development of borate BGs with tailored degradation profiles and excellent bioactivity, making them as strong candidates for various biomedical applications. [ABSTRACT FROM AUTHOR]

Lithium disilicate (LD) glass-ceramics used for bone repair need to have good mechanical properties and biological activity. Ion-exchange can lead a significant surficial strengthening and bioactivity of LD glass-ceramics. In this work, LD glass-ceramics were Li+/Ca2+@Li+/K+ exchanged in a mixed salt bath of 30 % Ca(NO 3) 2 + 70 % KNO 3 (in mol %) at 400 °C for 16 h, 32 h and 64 h respectively. LD glass-ceramics were significantly strengthened after Li+/Ca2+@Li+/K+ exchange. However, due to the shallow depth of the ion-exchange layer and stress relaxation, the strengthening effect deteriorated with the prolongation of the ion-exchange time. The Li+/Ca2+@Li+/K+ exchanged LD glass-ceramics could be conducive to the formation of the hydroxyapatite (HA) after soaking in the simulated body fluid (SBF). Moreover, the protein adsorption, cytotoxicity, cell adhesion, osteoblast proliferation and alkaline phosphatase (ALP) activity expression of Li+/Ca2+@Li+/K+ exchanged LD glass-ceramics were investigated. Ca2+ release might promote the bioactivity of ion-exchanged LD glass-ceramics. Therefore, Li+/Ca2+@Li+/K+ exchange can improve the mechanical properties and bioactivity of LD glass-ceramics, which has important significance for its application in orthopedic reconstruction. [ABSTRACT FROM AUTHOR]

Herewith, the present work reports a facile synthesis method of Bi 2 O 3 doped 70 SiO 2.30CaO binary bioactive glass system termed as modified Bi-BG (acronymed as mBi-BG) that indicates successful incorporation of Bi3+ into the silicate glassy network, on prior complex formation of the precursor bismuth nitrate salt with acetyl acetone to address the rapid decomposition rate of precursor bismuth nitrate. The binary bioactive glass composition as above mentioned (70 SiO 2.30CaO) is named as BG/Control. The synthesis methodology addresses inherent challenges encountered in traditional sol-gel derived bismuth oxide incorporated bioactive glass (Bi-BG) synthesis wherein yellow coloured bismuth oxide gets separated from the glassy network as confirmed by XRD phase analysis. Next, mBi-BG (modified Bi-BG) was synthesized via modifying the sol gel method by introducing a chelating agent acetyl acetone to stabilize the precursor Bi (NO 3) 3 salt, and was characterized using XRD, FTIR, FESEM-EDX. TG-DSC and BET isotherm. In vitro bioactivity studies illustrate the formation of hydroxyapatite crystals on mBi-BG surface indicating its potential for bone repair and regeneration. Additionally, mBi-BG exhibits significant effect against Staphylococcus aureus (gram-positive) bacterial strain, highlighting its utility in preventing bacterial infections at surgical sites. Radiographic imaging of mBi-BG reveals excellent radiopacity comparable to human bone, rendering it suitable for image-guided surgeries and fluoroscopic procedures. In summary, mBi-BG emerges as a versatile biomaterial with enhanced bioactivity, antibacterial efficacy and radiopacity, thereby offering novel avenues in medical treatment modalities and patient care. [Display omitted] • MBi-BG is a pure amorphous glassy composition. • MBi-BG composition possess radiopacity that would be beneficial for image guided medical interventions. • It is a biocompatible and bioactive composition. • MBi-BG offers superior antibacterial efficacy against gram-positive bacterial strain. [ABSTRACT FROM AUTHOR]

Bioactive glasses and glass-ceramics are biomaterials characterized by excellent bone bonding abilities. Many different bioactive glass formulations have been studied since the introduction of 45S5 bioglass by Larry Hench. Among silicate and borate bioglasses the phosphate-based ones seem to be interesting in drug delivery systems applications due to their high solubility and low toxicity. In this study novel phosphate bioactive glasses from the composition of P 2 O 5 – CaO – Ca(OH) 2 – KF – Na 2 O – TiO 2 and P 2 O 5 – CaO – Ca(OH) 2 – ZnO – KF –TiO 2 modified with 500 ppm or 2000 ppm of HAuCl 4 – 3H 2 O were obtained by traditional melt-quenching technique. Glass crystallization temperature was measured by DSC calorimetry. The bioglasses were partially crystallized above the crystallization temperature and the bioactive glass-ceramic based on the composition of the parent glasses was obtained. The FT-IR structural studies were performed to detect the presence of structural units beneficial for bioactivity of the materials. Crystalline phases of the bioglass-ceramics were identified with XRD. All bioglass-ceramics contained bioactive β-pyrophosphate. The obtained bioglasses and glass-ceramics were incubated in SBF to evaluate their bioactivity. Only P 2 O 5 – CaO – Ca(OH) 2 – KF– Na 2 O–TiO 2 bioglass-ceramics developed apatite-like layer on the surface after incubation in Simulated Body Fluid and was chosen as the material for future studies. The impact of the chemical composition of the bioglass, presence of particular structural units and bioglass-ceramic phase composition on the in vitro bioactivity was discussed. [ABSTRACT FROM AUTHOR]

Background: 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. Results: 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 ± 36.13 kPa) 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. Conclusion: 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. [ABSTRACT FROM AUTHOR]

This work focuses on combating bacterial infections in bone tissue using metal elements embedded in bioactive glass. While there is an urgent need for alternative methods with a shrinking number of effective treatment options untouched by antimicrobial resistance, it is crucial to first understand the mechanisms of pathogenesis, persistence, and bacterial resistance in skeletal infection, and then develop effective counterstrategies and innovative alternatives. This review considers the role of antimicrobial metal ions, their mechanism of action, and their incorporation into bioactive glass formulations as these materials can serve as delivery platforms with the least possible complexities. Furthermore, the bacterial infection risk in bone is also examined with specific attention to antibiotic resistance and biofilm formation. This review sheds light on the most promising materials as novel antibacterial agents by presenting a wide range of possible bioactive glass formulations equipped with potential antibacterial ions and in vitro/ in vivo insights, and it also reinforces the importance of continuing studies to develop multi‐faceted antibacterial bioactive glasses. [ABSTRACT FROM AUTHOR]

Calcium silicate cements (CSCs) are often used in endodontics despite some limitations related to their physical properties and antibacterial efficacy. This study aimed to develop and demonstrate the viability of a series of CSCs that were produced by sol-gel method and further modified with mesoporous bioactive glass nanoparticles (MBGNs) and collagen, for endodontic therapy. Calcium silicate (CS) particles and MBGNs were synthesized by the sol-gel method, and their elemental, molecular, and physical microstructure was characterized. Three CSCs were developed by mixing the CS with distilled water (CS+H 2 O), 10 mg/mL collagen solution (CS+colH 2 O), and MBGNs (10 %) (CSmbgn+colH 2 O). The mixing (MT) and setting (ST) times of the CSCs were determined, while the setting reaction was monitored in real-time. Antibacterial efficacy against Enterococcus faecalis (E. faecalis) and regenerative potential on dental pulp stem cells (DPSCs) were also analyzed. The CS+H 2 O displayed a ST comparable to commercial products, while CSmbgn+colH 2 O achieved the longest MT of 68 s and the shortest ST of 8 min. All the experimental CSCs inhibited the growth of E. faecalis. Additionally, compared to the control group, CSCs supported cell proliferation and spreading and mineralized matrix production, regardless of their composition. Tested CSCs presented potential as candidates for pulp therapy procedures. Future research should investigate the pulp regeneration mechanisms alongside rigorous antibacterial evaluations, preferably with multi-organism biofilms, executed over extended periods. [Display omitted] • Novel dental cements developed from calcium silicate, bioactive glass and collagen. • 10 % bioactive glass nanoparticles shorten the setting time of calcium silicate cement. • Developed calcium silicate cements are antimicrobial against E. faecalis. • Modest regeneration effect of mesoporous bioactive glass and collagen inclusion. [ABSTRACT FROM AUTHOR]

In this paper, boron (B)‐doped biphasic calcium phosphate (BCP)/poly(vinylidene fluoride) (PVDF) membrane scaffolds were developed by the combination of non‐solvent induced phase separation and lyophilization processes. In addition, the effects of the synthesized B‐incorporated BCP powders on the properties of the fabricated scaffolds were investigated. The physicochemical and morphological properties of the scaffolds were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy. The physical properties were evaluated by surface wettability and swelling measurements, whereas the mechanical properties were investigated by tensile strength measurements. The thermal behavior was determined by differential scanning calorimetry, the β‐crystallization ratio was calculated by FTIR, and the β‐phase structure was characterized by X‐ray diffraction. The bioactivity was evaluated in the simulated body fluid, and the cytotoxicity of the scaffolds was also investigated by performing in vitro cell culture experiments. The results showed that the incorporation of B into the PVDF matrix improved the hydrophilicity while reducing the degree of swelling of the scaffolds. Tensile strength was slightly reduced by the powder content, but yet the strength of all scaffolds was mechanically compatible with native bone. Increasing the B content up to 0.5 and 1 wt.% was improved the thermal properties, the β‐crystalline phase fraction, and thus the piezoelectricity. Furthermore, B‐doped BCP/PVDF‐based scaffolds significantly promoted bioactivity, cell viability, and proliferation without cytotoxicity, compared to the PVDF scaffold, depending on the B content. In conclusion, our results indicate that the PVDF‐based composites in the form of membrane scaffolds that support bone growth have the potential to be highly sought‐after candidates in the field of biomedical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Multifunctional bioactive biomaterials with integrated bone and soft tissue regenerability hold great promise for the regeneration of trauma-affected skin and bone defects. The aim of this research was to fabricate aerogel scaffolds (GD-BF) by blending the appropriate proportions of short bioactive glass fiber (BGF), gelatin (Gel), and dopamine (DA). Electrospun polyvinyl pyrrolidone (PVP)-BGF fibers were converted into short BGF through calcination and homogenization. Microporous GD-BF scaffolds displayed good elastic deformation recovery and promoted neo-tissue formation. The DA could enable thermal crosslinking and enhance the mechanical properties and structural stability of the GD-BF scaffolds. The BGF-mediated release of therapeutic ions shorten hemostatic time (<30 s) in a rat tail amputation model and a rabbit artery injury model alongside inducing the regeneration of skin appendages (e.g., blood vessels, glands, etc.) in a full-thickness excisional defect model in rats (percentage wound closure: GD-BF2, 98 % vs. control group, 83 %) at day 14 in vitro. Taken together, these aerogel scaffolds may have significant promise for soft and hard tissue repair, which may also be worthy for the other related disciplines. [ABSTRACT FROM AUTHOR]

Although poly-ether-ether-ketone (PEEK) implants hold significant medical promise, their bioinert nature presents challenges in osseointegration and bone ingrowth within clinical contexts. To mitigate these challenges, the present study introduces Diamond PEEK/bioactive glass (BG) composite scaffolds, characterized by macro/micro dual-porous structures, precisely fabricated via laser powder bed fusion (LPBF) technology. The findings indicate that an increase in BG content within these scaffolds significantly augments their hydrophilicity and hydroxyapatite formation capacities. Stress-strain curve analysis demonstrates reliable load-bearing stability across all scaffold types. In vitro assessments confirmed the non-cytotoxicity of PEEK/BG samples and demonstrated improved osteogenic differentiation and mineralization with increased BG incorporation. Further, in vivo experiments illustrated that the Diamond porous structure of these scaffolds facilitated bone growth, an effect notably amplified with higher BG content. Particularly in groups with 15 wt.% and 25 wt.% BG scaffolds, new bone formation was observed not only within the macropores of the Diamond structure but also within the micropores inside the scaffold rod, suggesting an almost seamless fusion with the new bone. This demonstrates the scaffolds' effective osteointegration and bone ingrowth properties. This study conclusively established the effectiveness of Diamond-structured PEEK/BG composite scaffolds, fabricated via LPBF, in bone repair. It highlights the crucial role of BG in enhancing osteogenic potential through interaction with the macro/micro pores of the scaffold. This study addresses the bioinert nature of PEEK implants by developing Diamond-structured PEEK/bioactive glass (BG) composite scaffolds by laser powder bed fusion. The dual-porous macro/microstructure enhances hydrophilicity and hydroxyapatite formation, vital for bone regeneration. By adjusting the BG content, we controlled the melt viscosity and sintering rate, leading to the formation of beneficial microscale pores. These pores resolve the issue of ineffective bioactive fillers in previous LPBF-fabricated scaffolds, enhancing the osteogenic potential of BG and inducing superior bone ingrowth and osseointegration. In vitro and in vivo analyses show enhanced osteogenic differentiation, mineralization, and bone growth, underscoring the clinical potential of these scaffolds for bone repair. [Display omitted] [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Metallic stainless steel bone implants are widely used due to their excellent mechanical properties, low cost, and ease of fabrication. Nanofibrous composite polymers have been proposed as coatings to promote biocompatibility and osseointegration, thanks to their biomimetic morphology that resembles the extracellular matrix. However, critical practical issues are often overlooked in the literature. For instance, applying coatings to implants with different shapes presents a significant technological challenge, as does evaluating viable sterilization procedures for hybrid devices containing electrospun polymers. In addition, infections pose a risk in any surgical procedure and can lead to implant failure, there is a need for antimicrobial prevention during surgery as well as in the short term afterward. In this work, we propose a new and straightforward method for manufacturing nanofibrous composite coatings directly on thin cylindrical-shaped metallic implants. Poly(ε-caprolactone) (PCL) nanofibers containing bioactive glass microparticles were electrospun onto stainless steel wires and then post-treated using two different strategies to achieve both hydrophilicity and surface disinfection. To address antimicrobial properties, amoxicillin-loaded Eudragit®E nanofibers were co-electrospun to impart pH-selective release behavior in event of a potential infection. The resulting composite hybrid coatings were characterized morphologically, physically, chemically, and electrochemically. The antibacterial behavior was evaluated at different media, confirming the release of the antibiotic in the pH range where infection is likely to occur. The impact of this study lies in its potential to significantly enhance the safety and efficacy of orthopedic implants by offering a novel, adaptable solution to combat infection. By integrating a pH-responsive drug delivery system with antimicrobial coatings, this approach not only provides a preventive measure during and after surgery but also addresses the growing issue of antibiotic resistance by targeting specific infection conditions. [ABSTRACT FROM AUTHOR]

Bone pathologies are still among the most challenging issues for orthopedics. Over the past decade, different methods are developed for bone repair. In addition to advanced surgical and graft techniques, polymer‐based biomaterials, bioactive glass, chitosan, hydrogels, nanoparticles, and cell‐derived exosomes are used for bone healing strategies. Owing to their variation and promising advantages, most of these methods are not translated into clinical practice. Three dimensonal (3D) bioprinting is an additive manufacturing technique that has become a next‐generation biomaterial technique adapted for anatomic modeling, artificial tissue or organs, grafting, and bridging tissues. Polymer‐based biomaterials are mostly used for the controlled release of various drugs, therapeutic agents, mesenchymal stem cells, ions, and growth factors. Polymers are now among the most preferable materials for 3D bioprinting. Melatonin is a well‐known antioxidant with many osteoinductive properties and is one of the key hormones in the brain–bone axis. 3D bioprinted melatonin‐loaded polymers with unique lipophilic, anti‐inflammatory, antioxidant, and osteoinductive properties for filling large bone gaps following fractures or congenital bone deformities may be developed in the future. This study summarized the benefits of 3D bioprinted and polymeric materials integrated with melatonin for sustained release in bone regeneration approaches. [ABSTRACT FROM AUTHOR]

Periprosthetic infection and prosthetic loosing stand out as prevalent yet formidable complications following orthopedic implant surgeries. Synchronously addressing the two complications is long‐time challenging. Herein, a bioactive glass scaffold (BGS) functionalized with MgCuFe‐layered double hydroxide (LDH)‐derived sulfide nanosheets (BGS/MCFS) is developed for vascularized osteogenesis and periprosthetic infection prevention/treatment. Apart from the antibacterial cations inhibiting bacterial energy and material metabolism, the exceptional near‐infrared‐II (NIR‐II) photothermal performance empowers BGS/MCFS to eliminate periprosthetic infections, outperforming previously reported functionalized BGS. The rough surface topography and the presence of multi‐bioactive metal ions bestow BGS/MCFS with exceptional osteogenic and angiogenic properties, with 8.5‐fold and 2.3‐fold enhancement in bone mass and neovascularization compared with BGS. Transcriptome sequencing highlights the involvement of the TGF‐β signaling pathway in these processes, while single‐cell sequencing reveals a significant increase in osteoblasts and endothelial cells around BGS/MCFS compared to BGS. [ABSTRACT FROM AUTHOR]

Excessive production of reactive oxygen species (ROS) around titanium implants under diabetic conditions causes persistent inflammation, leading to poor osseointegration and even implant failure. Surface modification is an effective way to promote ROS clearance, alleviate inflammation, and stimulate bone formation. In this study, a multifunctional coating is fabricated by introducing cerium (Ce)-containing mesoporous bioactive glass nanoparticles (Ce-MBGNs) onto the titanium surface via an electrophoretic deposition method. The incorporation of Ce-MBGNs remarkably improves surface hydrophilicity by increasing the surface areas. The bioactive ions are appropriately released, thereby promoting mesenchymal stem cell proliferation and differentiation under diabetic conditions. The conversion between Ce(III) and Ce(IV) endows Ce-MBGNs coating with antioxidative nanoenzymes properties to scavenge diabetes-induced ROS, resulting in macrophage polarization towards the anti-inflammatory phenotype. The therapeutic effect of Ce-MBGNs-modified titanium implants is also verified in diabetic rats by inhibiting inflammatory responses and accelerating early osseointegration. Taken together, the findings reveal that the ROS-scavenging and immunomodulation activity of the Ce-MBGNs coating contributes to enhanced osseointegration, and provides a novel implant surface for diabetic patients. [ABSTRACT FROM AUTHOR]

Abstract\nHIGHLIGHTSMesoporous bioactive glass, with its versatile characteristics and morphology, holds significant potential as an ideal hemostatic material. However, limited data is available regarding its toxicity levels. Consequently, this research intends to assess the acute and repeated dose dermal toxicity of Mesoporous antibacterial bioactive glass microsphere impregnated nonwoven surgical cotton gauze (MABGmscg) dressing in albino Wistar rats, following the standards set by the Organization for Economic Cooperation and Development. In the acute dermal toxicity study, the impact of MABG (@2000mg/kg BW) mscg dressing was assessed following a single dermal application in both male and female Wistar rats (n = 10). Mortality, clinical signs, body weight fluctuations and gross observations were consistently monitored over a14 day period following the single dose. The results indicated that, MABG (@2000mg/kg BW) mscg dressing upon dermal exposure did not cause any adverse effect in acute dermal toxicity study in Wistar rats compared to control group. Given that 2000 mg/kg BW of MABG was deemed a nontoxic dose, a repeated dose dermal toxicity study of MABGmscg dressing was subsequently conducted at three dose levels (@200, 500, 1000 mg/kg BW) over 28 consecutive days in Wistar rats. During the study period, no unscheduled deaths occurred, and there were no clinical signs associated with treatment, body weight variations or abnormal gross findings at necropsy in any groups. The analysis concluded that, MABGmscg dressing is safe to be considered as a hemostatic dressing at the various tested dose levels in Wistar rats.A dressing composed of mesoporous antibacterial bioactive glass impregnated into nonwoven surgical cotton gauze (MABGmscg) has been developed to serve as an effective hemostatic material.The acute and repeated dose dermal toxicity study of MABGmscg dressing has been performed in Wistar ratsNo visible changes or systemic effects were observed after applying the MABGmscg dressing at different doses for 28 consecutive days in Wistar rats.Therefore, the MABGmscg dressing is considered safe for use as a hemostatic gauze.A dressing composed of mesoporous antibacterial bioactive glass impregnated into nonwoven surgical cotton gauze (MABGmscg) has been developed to serve as an effective hemostatic material.The acute and repeated dose dermal toxicity study of MABGmscg dressing has been performed in Wistar ratsNo visible changes or systemic effects were observed after applying the MABGmscg dressing at different doses for 28 consecutive days in Wistar rats.Therefore, the MABGmscg dressing is considered safe for use as a hemostatic gauze. [ABSTRACT FROM AUTHOR]

Bioactive glasses (BGs) bond with bone by forming hydroxy carbonate apatite (HCA) upon reaction in physiological fluid, a phenomenon known as bioactivity. BGs structural network connectivity determines their bioactivity. Sol–gel BGs are synthesized through the hydrolysis and condensation of metal alkoxide precursors in the presence of a catalyst, in aqueous environments. Several sol–gel synthesis parameters directly impact BG network connectivity: pH (i.e. acid or basic catalysis), water to alkoxide ratio (R w), alkoxide type and presence of dopant ions. However, the relationship between bioactivity and these parameters remains surprisingly unexplored. This study highlights the relationship between synthesis pH, R w , network connectivity and bioactivity in silica-based sol-gel BGs and BGs doped with titanium (Ti) ions (TiBGs), the latter selected for their known ability to enhance network connectivity. BGs and TiBGs are synthesized with various R w values under acidic and basic conditions, and their bioactivity is assessed in simulated body fluid for 7 days. Increasing R w decreases network connectivity and increases bioactivity of BGs with high network connectivity, as observed for base-catalyzed BGs and for both acid and base catalyzed TiBGs, but not in BGs with lower connectivity as evidenced in acid-catalyzed BGs. Basic catalysis of TiBGs prevents crystalline TiO 2 domain formation, which was instead consistently observed in TiBGs synthesized under acidic catalysis. These findings help the design of BGs for applications where ion release needs to be enhanced even in the presence of dopants that slow down HCA formation, and of BGs with specific properties, e.g. TiO 2 -containing BGs with potential bactericidal activity. Bioactive glasses (BGs) bond with bone by dissolving and forming hydroxycarbonate apatite (HCA) on their surface, offering applications in medicine and dentistry. BG's network connectivity influences its dissolution rate, and hence HCA formation. While solution-gelation (sol-gel) is commonly used for BG production, the effect of sol gel synthesis parameters on HCA formation remains unexplored. We studied the relationship between synthesis parameters (water-to-alkoxide ratio (R w), catalyst, and dopant ions, particularly titanium), BG network connectivity, and HCA formation. We find that increasing R w with any catalyst enhances HCA formation, particularly in glasses with high network connectivity. This understanding allows tailoring BG synthesis for different applications, e.g. those requiring doping with ions that increase network connectivity and fills a crucial gap in BG literature. [Display omitted] [ABSTRACT FROM AUTHOR]

Shakhmatkin and Vedishcheva thermodynamic model (SV TDM) of 45S5 bioglass was evaluated at T = 800 K. From 42 considered system components, only 7 components (Na2O⋅SiO2, Na2O⋅3CaO⋅6SiO2, 3CaO⋅2SiO2, CaO⋅SiO2, 9Na2O⋅6SiO2⋅2P2O5, 2CaO⋅SiO2, and Na2O⋅2CaO⋅P2O5) were present in significant equilibrium molar amount. The calculated Q-distribution of silicate units (22.6% of Q3, 63.1% of Q2, 10.1% of Q1, and 4.2% of Q0) was compared with the Q-distribution for so-called crystalline reference state (6.3% of Q3, 93.7% of Q2). Further, both Q-distributions were compared with the MAS NMR experimental data published by different authors (e.g. 33.3% of Q3, 54.5% of Q2, and 12.2% of Q1, or 17.8% of Q3, 76.7% of Q2, and 5.5% of Q1). It was concluded that there is no principal difference between SV TDM and MAS NMR distributions of silicate units. Further the Q-distribution of phosphate units was analysed. The CRS resulted in 100% presence of Q0 units (i.e. PO43−). The SV TDM resulted in significantly broader distribution, i.e. 4.5% of Q2, 10.4% of Q1, and 85.1% of Q0. This distribution is comparable with those obtained by MAS NMR (e.g. 26.7% of Q1 and 73.3% of Q0). [ABSTRACT FROM AUTHOR]

The editorial in the journal "Bioengineering" discusses the challenges posed by maxillofacial defects and the limitations of current treatments involving autologous bone grafts and prosthetic devices. The editorial highlights innovative approaches such as using biomaterials combined with stem cells for bone regeneration, exploring the impact of sintering temperatures on bone graft properties, and utilizing laser-assisted surface patterning to enhance cell organization. Reviews in the article focus on the potential of silica-based inks in 3D printing for bone tissue engineering and the use of nanomaterials in periodontal tissue engineering. Additionally, the article discusses the use of laser soldering technology for soft tissue reconstruction and a novel imaging technique for early detection of dental caries. The future of maxillofacial defect treatment lies in personalized approaches, advanced technologies, and regenerative medicine to improve patient outcomes and advance clinical practice. [Extracted from the article]

There has been a good deal of research on improving the corrosion behavior of magnesium (Mg) by polycaprolactone (PCL) coating, albeit with destroying bioactivity and hydrophilicity. The adhesion of a polymeric layer to the surface of the metal is also a knotty problem. On the other hand, the micro-arc oxidation (MAO) process is a new method that can create thin films with desirable adhesion to the surface of the implants although these films could hardly control the degradation of Mg. In this research, a multifunctional nanocomposite coating showing significant adhesion to the surface of the substrate has been fabricated that can enhance not only the corrosion but also the bioactivity of Mg-based biomaterials. It can also improve their biological, antibacterial, and osteogenesis properties. The fabrication process of this multifunctional composite coating with these desirable features can be broadly separated into three main stages beginning with synthesizing strontium (Sr) and copper (Cu) doped bioactive glass nanoparticles (BGNs), applying micro-arc oxidation (MAO) nanocomposite coating on the surface of pure Mg, and finally sealing the pores of MAO layer by PCL with BGNs containing Sr and Cu at concentrations of 5, 10, and 15 wt%. After this process, the corrosion resistance, bioactivity, antibacterial, and cytotoxicity of Mg-based samples were assessed. It was found that the addition of 10 wt% of BGNs in the MAO-PCL nanocomposite enhanced corrosion resistance (78,343.358 KΩ.Cm2), bioactivity, cellular viability and antibacterial property (99%) of Mg-based scaffolds, which can be widely used in bone tissue engineering. [ABSTRACT FROM AUTHOR]

The biodegradability of magnesium (Mg) metal implants necessitates surface modification to mitigate the high corrosion rate in the body's physiological environment. This study focuses on synthesizing and applying a nanocomposite coating of polydimethylsiloxane-nanosized bioactive glass (PDMS-nBG) on the surface of a plasma electrolytic oxidation (PEO)-modified AZ91 Mg alloy. The PDMS-1 wt% nBG nanocomposite coating was deposited on the PEO-treated substrate using the dip-coating method. Surface and cross-sectional morphologies of the nanocomposite coatings were examined using field emission scanning electron microscopy (FESEM). Corrosion behavior of the AZ91 substrate, PEO coating, and double-layer PEO/PDMS-nBG coating was investigated using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) tests. Results showed that the corrosion resistance and corrosion current density of Mg substrates increased and decreased from 4815 Ω.cm2 and 8.96 µA.cm− 2 to 18 MΩ.cm2 and 0.00016 µA.cm− 2 for AZ91 and PEO/PDMS-nBG coating, respectively. Additionally, the morphology and adhesion of cultured human mesenchymal cells on the PEO-modified AZ91 substrates with a single PDMS polymer coating and a PDMS-nBG nanocomposite coating were investigated using fluorescent light microscopy and FESEM. The PEO/PDMS-nBG bilayer coating effectively addressed the limitations of magnesium alloys and holds potential for biomedical applications, particularly in orthopedic implants, due to the enhanced biocompatibility and bioactivity of Mg alloys. [ABSTRACT FROM AUTHOR]

Silicate glasses containing silicon, sodium, phosphorous, and calcium have the ability to promote bone regeneration and biodegrade as new tissue is generated. Recently, it has been suggested that adding SrO can benefit tissue growth and silicate glass dissolution. Motivated by these recent developments, the effect of SrO/CaO–CaO/SrO substitution on the local structure and dynamics of Si-Na-P-Ca-O oxide glasses has been studied in this work. Differential thermal analysis has been performed to determine the thermal stability of the glasses after the addition of strontium. The local structure has been studied by neutron diffraction augmented by Reverse Monte Carlo simulation, and the local dynamics by neutron Compton scattering and Raman spectroscopy. Differential thermal analysis has shown that SrO-containing glasses have lower glass transition, melting, and crystallisation temperatures. Moreover, the addition of the Sr2+ ions decreased the thermal stability of the glass structure. The total neutron diffraction augmented by the RMC simulation revealed that Sr played a similar role as Ca in the glass structure when substituted on a molar basis. The bond length and the coordination number distributions of the network modifiers and network formers did not change when SrO (x = 0.125, 0.25) was substituted for CaO (25-x). However, the network connectivity increased in glass with 12.5 mol% CaO due to the increased length of the Si-O-Si interconnected chain. The analysis of Raman spectra revealed that substituting CaO with SrO in the glass structure dramatically enhances the intensity of the high-frequency band of 1110–2000 cm−1. For all glasses under investigation, the changes in the relative intensities of Raman bands and the distributions of the bond lengths and coordination numbers upon the SrO substitution were correlated with the values of the widths of nuclear momentum distributions of Si, Na, P, Ca, O, and Sr. The widths of nuclear momentum distributions were observed to soften compared to the values observed and simulated in their parent metal-oxide crystals. The widths of nuclear momentum distributions, obtained from fitting the experimental data to neutron Compton spectra, were related to the amount of disorder of effective force constants acting on individual atomic species in the glasses. [ABSTRACT FROM AUTHOR]

Preparing electrospun fibers by applying a potential difference between a polymeric solution and a contacting substrate is increasingly attracting attention in tissue engineering applications. Among the numerous polymers, polycaprolactone (PCL) bioscaffold has been widely investigated due to its biocompatibility and biodegradability. Bioactive powder can be added to further improve its performance. In the present study, bioactive glass powder modified by adding 0–6 wt.% antibacterial zinc element (coded as ZBG) was prepared through the sol–gel process. Furthermore, PCL bioscaffolds with various ZBG additions were prepared using the electrospinning technique. The zinc-doped bioactive glass powder and electrospun PCL/ZBG bioscaffolds were evaluated using scanning electron microscopy, X-ray diffraction and Fourier-transform infrared spectroscopy to determine their structural properties. Additionally, in vitro bioactivity, biocompatibility and antibacterial performance were investigated. Experimental results showed that sol–gelled ZBG powder possessed superior bioactivity and 0.8 g ZBG was the optimal addition to prepare PCL/ZBG bioscaffolds with. All the electrospun PCL/ZBG bioscaffolds were biocompatible and their antibacterial performance against two S. aureus strains (SA133 and Newman) improved with increasing zinc concentration. Electrospun PCL/ZBG bioscaffolds exhibited excellent bioactivity and have great potential for biomedical application. [ABSTRACT FROM AUTHOR]

Hemorrhage control is crucial in both military and civilian contexts. Despite unprecedented improvements in hemostatic products, efficient treatment solutions to control hemorrhage upon wound healing are still necessary. Chitosan (CS) and dextran (Dex) are natural, biocompatible and biodegradable hydrogel-forming polysaccharides with enhanced hemostatic and wound healing properties. Bioglass nanoparticles (BG-nps) in turn possess documented hemostatic properties. In this context, in the present work, a series of BGnps-doped chitosan (CS)/oxidized-dextran (ODEX) adhesive sponges were developed through a Schiff base reaction. The successful synthesis of the materials was confirmed by FTIR spectroscopy, their crystallinity was analyzed by XRD, the sponge morphology was investigated by SEM analysis, water swelling, and viscosity of the hydrogels were also investigated. All materials were developed in powder and sponge form with the aim to allow their application to wound lesions of any shape and depth and enable suppression of external bleeding for which other methods of bleeding control are not applicable. All prepared hemostatic products showed hemocompatibility, and it was observed that the CS-ODEX-BGnps sponges decreased the blood clotting time compared to CS neat and mainly those with the highest percentages of BGnps (1% and 2% w/w). [ABSTRACT FROM AUTHOR]

High-strength alumina (Al2O3 ) was utilized as a reinforcing phase to improve the strength of hydroxyapatite (HA), a bioactive material, but the HA-Al2O3 ceramics prepared by traditional hydrothermal method could not achieve the precise control of pore size and porosity, whereas the light curing additive manufacturing technology could achieve the high precision molding of HA-Al2O3 ceramics through the high-performance photocurable slurry. The state of HA-Al2O3 slurry is adjusted by the addition of dispersant, photoinitiator, and photoabsorbent to alleviate the severe scattering effect caused by the refractive index mismatch between HA powder, Al2O3 powder, and photosensitive resin. In this study, the effects of the type and content of photoinitiator and dispersant on the slurry were explored. The rheological and curing properties of the slurry are first improved and then weakened with the addition of both, and the optimal dosages of photoinitiator and dispersant are 0. 5% and 4% (mass fraction), respectively. The effects of two light absorbers, graphite and methyl yellow, on improving the printing accuracy were compared. Although graphite improves the printing accuracy and rheology of the slurry, it reduces the printing quality, so the dosage of 5.0 x 10-5 methyl yellow is determined, and finally HA-Al2O3 slurries suitable for high precision printing are obtained. [ABSTRACT FROM AUTHOR]

Fabricating large-scale porous bioactive glass bone scaffolds presents significant challenges. This study aims to develop formable, in situ setting scaffolds with a practical gelation time of about 10 min by mixing 45S5 bioactive glass with sodium silicate (waterglass) and an acid initiator. The effects of pH (2–11), waterglass concentration (15–50 wt.%), and acid initiator type (phosphoric or boric acid) were examined to optimize gelation kinetics and microstructure. A 10 min gelation time was achieved with boric acid and phosphoric acid at various pH levels by adjusting the waterglass concentration. Exponential and polynomial models were proposed to predict gelation times in basic and acidic environments, respectively. The optical properties of the gels were studied qualitatively and quantitatively, providing insights into gelation kinetics and structure. Acidic gels formed smaller particles in a dense network (pores < 550 nm) with higher light transmittance, while basic gels had larger aggregates (pores ~5 µm) and lower transmittance. As the waterglass concentration decreased, pore size and transmittance converged in both groups. The onset of gelation was detected around 8 min using the derivative of light transmittance. This work identifies the key factors controlling waterglass gelation and their impact on gel structure, enabling the tailored creation of formable, in situ setting bioactive glass bone scaffolds. [ABSTRACT FROM AUTHOR]

Regeneration of bone defects in diabetic patients has always been a significant challenge in clinical treatment. The pathologic diabetic micromilieu, characterized by mitochondrial dysfunction, excessive reactive oxygen species (ROS) accumulation, cellular senescence, and chronic inflammation, compromises innate bone healing capacity. 3D cryo‐printing technology is utilized in bone tissue engineering to fabricate hierarchical porous scaffolds that promote a conducive microenvironment for cellular adhesion, migration, proliferation, and nutrient exchange. Nanozymes are used as synthetic mimics of natural enzymes to scavenge ROS, addressing the limitations of natural antioxidative enzymes. To remodel the diabetic bone regeneration micromilieu, a 3D cryo‐printed polyaryletherketone with carboxyl groups (PAEK‐COOH) and 45S5 bioactive glass (BG) hierarchical porous scaffold (PBG scaffold), harmonized with hybrid nanozymes comprising SS31‐enhanced manganese dioxide (MnO2)‐ferritin biomimetic nanozyme (MF@S nanozyme), is developed for combinatorial mitochondrial therapy. The MF@S nanozyme specifically targets mitochondria to enhance mitochondrial function, scavenge ROS accumulated in mitochondria, and suppress mitochondrial ROS (mtROS) production, and thus rejuvenate aging cells, regulate macrophage polarization, and modulate differentiation of osteoblasts and osteoclasts. This 3D cryo‐printed PBG‐MF@S hierarchical porous scaffold combines with a combinatorial mitochondrial therapy system to remodel the diabetic micromilieu and presents a promising therapeutic approach for the regeneration of bone defects in diabetes. [ABSTRACT FROM AUTHOR]

Hydrogel dressings are emerging as a promising option for the treatment of chronic wounds due to their tailorable functional properties, which can accelerate the healing. These properties can be improved by the addition of fillers such as bioactive glasses (BGs), and among these, mesoporous glasses doped with cerium (Ce-MBGs) also loaded with polyphenols (Ce-MBGs-POLY) are of interest for their antioxidant properties and dissolution behavior. Here we report the synthesis and characterization of stable hydrogels with high water content and swelling ratio (80 %) containing Ce-MBGs or Ce-MBGs-POLY. These hydrogels show a fast and significant release of ions aimed at stimulating cellular functions and retain the excellent antioxidant properties of the fillers. The new composites are thus promising starting points for the development of injectable hydrogels for chronic wound healing. [ABSTRACT FROM AUTHOR]

The development of biocompatible materials, which both facilitate wound healing and possess antimicrobial properties, continues to present a formidable challenge. However, recent research has increasingly acknowledged the pivotal role that macrophages play in the repair of wounds associated with infection. In this study, a novel sequential immunomodulation strategy is proposed, which involves the preparation of hydrogels encapsulating vancomycin-loaded lithium (Li) mesoporous bioactive glass (Li-MBG) within methacrylate silk fibroin (SilMA) hydrogel. The fabricated SLM@V hydrogel exhibited enhanced capabilities for vancomycin and Li ion release, adjustable mechanical properties, and a porous network structure. Cytocompatibility assessments revealed that SLM@V hydrogels exhibit favorable compatibility in vitro. Importantly, SLM@V hydrogels demonstrate significant bactericidal and anti-inflammatory properties in vitro. In a murine model of skin defects, SLM@V hydrogels facilitated the complete healing of infected wounds. Furthermore, histological and immunohistochemical analyses substantiated the effectiveness of SLM@V hydrogels in enhancing granulation tissue formation, promoting collagen deposition, and mitigating inflammation and angiogenesis. Consequently, the composite hydrogel synthesized in this research has the potential to expedite the healing process of infection-related wounds in a secure and efficient manner. This innovative composite hydrogel material offers a novel strategy to tackle the complexities associated with infection-induced wound healing. [ABSTRACT FROM AUTHOR]

This study focuses on the relationship between porosity, surface roughness, microstructure, strength, and thermal properties, as well as their effect on the bioactivity and biodegradability of fabricated akermanite (AK; Ca 2 MgSi 2 O 7) bioceramic scaffolds. Firstly, we prepared the AK nanopowders using the mechanical activation method, mixed them with varying proportions of space-holder agent (NaCl), specifically 15, 20, 30, 40, and 50 vol%, and sintered them at 1200 °C to create porous scaffolds. We investigated the physical properties and microstructure using the Archimedes method and field emission scanning electron microscopy (FE-SEM), respectively. The mechanical properties in terms of microhardness, compressive strength, longitudinal modulus, Young's modulus, bulk modulus, and shear modulus were measured. The bioactivity and biodegradability of prepared scaffolds were assessed after soaking in simulated body fluid (SBF) for 10 days by FE-SEM and inductively coupled plasma-atomic emission spectroscopy (ICP-AES), respectively. The results revealed that porous scaffolds with suitable mechanical properties, bioactivity, and biodegradability were prepared. The porosity had a significant impact on the mechanical and biodegradability of the investigated scaffolds. It reduced mechanical properties slightly while improving bioactivity and biodegradability. The microstructure study displayed that all scaffolds formed apatite layer on their surfaces. This is because of good bioactivity and the suitable porosity level of AK. The obtained findings provide promising prospects for the future use of AK in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Bioactive glasses (BG) containing silicon, phosphorous, and boron have emerged as promising materials for bone tissue engineering. Modifying ions play a multifaceted role in BGs, influencing their structure, properties, and biological activity that depends on their size, charge, and coordination chemistry. This study investigates the addition of sodium borate (Na 2 B 4 O 7) to the 58S BG and the mixed alkali effect (MAE) resulting from incorporating Na and B ions into the CaO–SiO 2 –P 2 O 5 system. In specific concentrations, Na+ and Ca2+ ions function as network modifiers, introducing structural disruptions and generating defects that impact the glass transition temperature (T g), crystallization temperature (T c), hardness, and sintering characteristics. The physicochemical characterization of BGs confirms the incorporation of Na and B structures. Furthermore, the Na and B doped glass sample with a [Na/Si] ratio of 0.045 exhibits favorable properties for promoting cell attachment, including forming a hydroxyapatite (HAp) layer over the surface, thereby accelerating human placental mesenchymal stem cells (hPMSCs) proliferation. The findings demonstrate the potential of Na 2 B 4 O 7 incorporation in BG for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Bioactive ceramic bone scaffolds are limited by their brittleness. To address this limitation, we developed a new method for preparing β-tricalcium phosphate (β-TCP)/polycaprolactone (PCL) porous composite scaffolds with a gradient structure using digital light processing technology and an impregnation process. The composite scaffolds exhibited compressive strength comparable to that of pure β-TCP scaffolds but with substantially higher toughness and reliability, especially during in vitro degradation. Owing to the gradient structure, the composite scaffolds could gradually shift from high strength and stiffness to moderate strength and low stiffness, which is beneficial for bone healing and remodeling. In femoral condyle defects without mechanical stimulation, the β-TCP/PCL composite scaffolds exhibited slightly lower cellular compatibility and osteoinductive ability than those of the pure β-TCP scaffolds. However, in radial defects, composite scaffolds demonstrated a better mechanical response and bone growth capacity. The composite scaffolds maintained their structural integrity after 2–4 months, whereas the β-TCP scaffolds fractured within 2 months. This study provides a novel methodology for the development of effective scaffold fabrication strategies for load-bearing or large segmental defects with complex stress applications for use in bone healing and remodeling. [ABSTRACT FROM AUTHOR]

Commercially available bioactive glasses (BAGs) are exclusively used in powder form, due to their tendency to crystallize. Silicate BAG 1393 was developed to allow fiber drawing and scaffold sintering, but its slow degradation limits its potential. To enable scaffold manufacturing while maintaining glass dissolution rate close to that of commercially available BAGs, the borosilicate glass 1393B20 was developed. This study investigates the potential of 1393B20 scaffolds to support bone regeneration and mineralization in vitro and in vivo , in comparison to silicate 1393. Both scaffolds supported human adipose stem cells proliferation, either in direct contact for the 1393, or mainly around for the 1393B20. Similarly, both BAGs induced osteogenesis and angiogenesis in vitro , with a better pro-angiogenic influence of the 1393B20. In addition, these scaffolds supported bone regeneration and osteoclast/osteoblast activity in vivo in critical-sized rat calvarial defect. Nevertheless, mineralization and collagen formation were significantly enhanced for the 1393B20, at 3-months post-implantation, assigned to faster and more complete dissolution of the scaffolds. Thus, 1393B20 demonstrates greater promise for bone tissue engineering certainly due to its time-controlled release of boron and silicon. Bioactive glasses (BAGs) show great promise in bone tissue engineering as they effectively bond with bone tissue, fostering integration and regeneration. Silicate BAG 1393 was developed to allow fiber drawing and scaffold sintering, but its slow degradation limits its potential. To enable scaffold manufacturing while maintaining glass dissolution rate close to that of commercially available BAGs, the borosilicate glass 1393B20 was developed. Both BAGs induced osteogenesis and angiogenesis in vitro , with a better pro-angiogenic influence of the 1393B20. The presence of boron in the 1393B20 enhanced mineralization and collagen formation in vivo compared to 1393, probably due to its faster dissolution rate. Here, 1393B20 demonstrated greater promise for bone tissue engineering compared to the well-known 1393 BAG. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: White spot lesions (WSL) are common side effects of orthodontic treatment with fixed appliances, in which the surface layer of enamel is demineralised. Thus, remineralisation, that is a partial or complete reversal, of these lesions can occur as they affect the surface enamel. Remineralisation with low-dose fluoride, in addition to optimal oral hygiene and diet, has been recommended to manage WSL. The aim of the planned trial is to assess the effectiveness of a fluoride-containing bioactive glass toothpaste (BioMin™) in its ability to remineralise post-orthodontic demineralised WSL. Methods: A single-centre, double-blind randomised clinical trial to assess intervention with Bio-Min toothpaste on WSL forming on the teeth of young people completing orthodontic treatment. Discussion: Remineralisation of WSL can vary depending on the individual and the site of the lesion. There is a range of oral fluoride delivery methods which include toothpastes, oral rinses, and gel preparations, which can aid remineralisation of these lesions. Identifying effective methods of remineralisation to manage this common and unsightly complication of fixed appliance therapy can improve the health and aesthetics of dentition. Trial registration: ISRCTN.com International Standard Randomised Controlled Trials Number (ISRCTN) 14479893. Registered on 14 May 2020 [ABSTRACT FROM AUTHOR]

One of the challenges and limitations of bone tissue engineering includes fast degradation rates, reduced bioactivity, donor site morbidity, and unresolved risks of pathogen transmission. In the field of bone tissue engineering, gradient materials are promising for treating bone defects because they can create graded structures and compositions similar to natural bone. By controlling the amount of components in the structure, the degradation rate, bioactivity, and osteogenic capacity can be manipulated. In the current study, a gradient, multilayer, porous nanocomposite of calcium sulfate/glass (Gn CS/BG) with a gelatin coating (Gn CS/BG-Gel) was prepared using rotational casting technique. The SEM results showed an average pore size of approximately 400 μm within the Gn CS/BG-Gel nanocomposite. An elastic modulus (E) of around 240 MPa and an ultimate tensile strength (σ) of approximately 5.5 MPa were achieved for Gn CS/BG-Gel nanocomposite. The degradation analysis in a dynamic tris-buffer environment revealed a degradation rate of 68 % over a 63-day period, with a decrease in degradation rate as the bioactive glass (BG) content increased in each layer, indicating the influence of BG on the degradation process. The bioactivity results in a dynamic simulated body fluid suggested that increased BG content in each layer promoted hydroxyapatite formation, indicating improved bioactive behavior. The evaluation of ion release with ICP-OES, MTT and Acridine Orange assays using human bone marrow-derived mesenchymal stem cells (hBMSCs) confirmed the non-toxic nature of Gn CS/BG-Gel. Assessments of alkaline phosphatase (ALP) activity, calcium content, Alizarin Red staining and cell attachment behavior substantiated the osteogenic potential of Gn CS/BG-Gel. Collectively, the three-dimensional structure along with the Gn CS/BG-Gel composition contributed to the enhanced cellular responses. These findings hold significant promise for the development of biomaterials with potential applications in bone tissue engineering, and they contribute valuable insights to the field. [Display omitted] [ABSTRACT FROM AUTHOR]

Bioactive glasses are renowned for their applications in dentistry, serving as restorative materials, dental adhesives, intracanal medicaments, and agents for enamel remineralization. Niobium pentoxide (Nb 2 O 5) is employed in dental adhesive resins and orthodontic adhesives, offering radio-pacifying properties essential for dental materials. Samarium oxide (Sm 2 O 3) emerges as a potential additive in aesthetic restorative dental ceramics and resins, enhancing the natural fluorescence of teeth. In this study Nb 2 O 5 and Sm 2 O 3 -doped (1, 3, and 5 wt%) 13–93 bioactive glass particles were synthesized via the sol-gel method, tailored for dental implementations. We conducted a comprehensive analysis of the physical, structural, and optical properties of the resultant glass powders. Additionally, their in vitro bioactivity and ionizing radiation shielding characteristics were rigorously evaluated. The results indicate that Sm3+ ions preserve the amorphous nature of the silicate glasses, while Nb5+ incorporation leads to the crystallization of the T-Nb 2 O 5 phase. Bioactivity assays across three physiological fluids—simulated body fluid, α-minimum essential medium, and phosphate-buffered saline, demonstrated the ability of doped glasses to facilitate hydroxyapatite layer formation, with the most pronounced bioactivity observed in phosphate-buffered saline immersed samples. Furthermore, radiation shielding simulations reveal that the addition of Nb 2 O 5 and Sm 2 O 3 enhances the ionizing radiation attenuation capabilities of the glasses, a property that holds significant promise for protecting against radiation in dental radiology. It can be concluded that the dual functionality of Nb5+ and Sm3+-doped bioactive glasses, which may revolutionize restorative dental practices and offer improved protection in radiological applications. [ABSTRACT FROM AUTHOR]

The preparation of scaffolds that are both macroporous and mechanically strong is a significant challenge in the development of bioactive ceramic materials for bone substitution. Furthermore, the introduction of beneficial extra-functionalities such as bacterial inhibition is highly appealing but adds complexity to implant design and production. In this study, we aimed to fabricate highly porous, bioactive and antibacterial glass-ceramic scaffolds with interconnected macropores through the foam replica method. The scaffolds were sintered at two different temperatures (620 and 850 °C), yielding glassy or partially crystallized materials, respectively. The scaffold produced at higher temperature was found to be highly porous (>75 vol%), mechanically stronger and able to induce hydroxyapatite formation after three days of soaking in SBF (in vitro bioactivity). In order to confer antibacterial activity, silver (Ag) ions were introduced onto the scaffold surface through ion exchange in an aqueous solution. Compositional analysis confirmed the successful doping of the scaffold surface with silver, which was continuously released in SBF for at least 28 days, as revealed by ICP-MS. Finally, the antibacterial action of the Ag-doped scaffold was confirmed towards Staphylococcus epidermidis. Overall, the results reported in this work show the potential of foam-like Ag-doped bioactive glass-ceramic scaffolds to be used in applications requiring bone substitution and antibacterial properties. [ABSTRACT FROM AUTHOR]

Bioactive glass ceramics (BGC) play a pivotal role in bone tissue engineering, specifically addressing challenges associated with bone repair and regeneration. In this study, we developed silica-based 55S0P and 45S10P spherical BGC nanoparticles (NPs), without and with P 2 O 5 content, using a modified Stöber sol-gel process with base hydrolysis. The fabricated spherical NPs with pronounced textural features effectively contribute to enhanced surface roughness, a desirable parameter for improved biological activity in physiologically relevant solutions and tissue matrices. A comprehensive evaluation of the structural properties of these novel spherical BGC-NPs using diverse characterization techniques revealed distinct nano-textural features in the form of cracks and pores. The HR-TEM confirmed the nanoscale dimensions (170–190 nm) of particles with spherical surface morphology and also systematically analysed via DLS, FE-SEM studies. An augmented surface area with mesopores when phosphate added to the silica glass network was revealed by BET analysis. On the biological front, the study records the formation of an HCA layer on the surfaces of the BGC-NPs, the thickness of which increased with an increase in both phosphate content and immersion time (0, 3, 14 & 28 days) in the SBF solution. The zeta potential values attain a maximum from −22 mV to −23.6 mV for 55S0P and −21.5 mV to −26.4 mV for 45S10P BGC-NPs, and improved with increased immersion time, thereby favouring cellular adhesion for desired biological responses. In vitro, cell culture studies on MG-63 cells, after 24 and 72 h of incubation, demonstrated higher cell adhesion and proliferation, with pronounced biocompatibility. In addition, these BGC-NPs exhibited good hemocompatibility even at the highest test concentration (15 mg/ml) and demonstrated effective antibacterial activity against K. pneumoniae and E. coli. A combinatorial analysis of structural and biological properties revealed that the 45S10P BGC-NPs are more potent than 55S0P BGC-NPs for desired biological performances. In conclusion, the results suggest that the sol-gel fabricated BGC-NPs with enhanced nano-textural features are evidently suitable for applications in bone tissue engineering and regenerative medicine. [Display omitted] • Design and development of BGC-NPs (55S0P and 45S10P) via modified Stöber's method. • Confirmation of enhanced textural features by BET, FE-SEM and HR-TEM analyses. • Obtained high negative Zeta values supporting improved surface reactivity for bio-compatible applications. • Identification of HCA layer by Optical Absorption (OA), supported by XRD, FTIR & FE-SEM. • Enhanced cell viability, hemocompatibility and antibacterial activity with P 2 O 5 content for bone regenerative applications. [ABSTRACT FROM AUTHOR]

Despite advances in treating osteosarcoma, postoperative tumor recurrence, periprosthetic infection, and critical bone defects remain critical concerns. Herein, the growth of selenium nanoparticles (SeNPs) onto MgFe‐LDH nanosheets (LDH) is reported to develop a multifunctional nanocomposite (LDH/Se) and further modification of the nanocomposite on a bioactive glass scaffold (BGS) to obtain a versatile platform (BGS@LDH/Se) for comprehensive postoperative osteosarcoma management. The uniform dispersion of negatively charged SeNPs on the LDH surface restrains toxicity‐inducing aggregation and inactivation, thus enhancing superoxide dismutase (SOD) activation and superoxide anion radical (·O2−)‐H2O2 conversion. Meanwhile, Fe3+ within the LDH nanosheets can be reduced to Fe2+ by depleting glutathione (GSH) in the tumor microenvironments (TME), which can catalyze H2O2 into highly toxic reactive oxygen species. More importantly, incorporating SeNPs significantly promotes the anti‐bacterial and osteogenic properties of BGS@LDH/Se. Thus, the developed BGS@LDH/Se platform can simultaneously inhibit tumor recurrence and periprosthetic infection as well as promote bone regeneration, thus holding great potential for postoperative "one‐stop‐shop" management of patients who need osteosarcoma resection and scaffold implantation. [ABSTRACT FROM AUTHOR]

Particulate bone grafting material can travel from the implantation site and diminish the magnitude of required bone formation response and hence its effectiveness. An easily prepared moldable graft that rapidly sets rigid in situ would alleviate this problem and in this study, such an injectable bone graft material is presented. By combining calcium phosphate (CP) salts with a bioactive glass (BG) mixed with a 2.5% Na2HPO4 solution a novel BG‐based calcium phosphate cement (CPC) is produced. Immersion in Tris buffer and simulated body fluid (SBF) solutions result in the rapid generation of octacalcium phosphate (OCP) and hydroxyapatite (HA) phases – a pre‐requisite for "bioactivity". Cement‐conditioned media does not result in any cytotoxic potential with respect to MTT activity, DNA content, or alkaline phosphatase activity with an osteoblastic cell line. Application of the cement into standardized surgical defects in the minipig mandible results in short‐term, moderate irritation at 3 and 6 weeks and complete replacement of cement with new bone at 12 weeks. [ABSTRACT FROM AUTHOR]

In this study, we adapted an HP D100 Single Cell Dispenser -- a novel low-cost thermal inkjet (TIJ) platform with impedance-based single cell detection -- for dispensing of individual cells and one-pot sample preparation. We repeatedly achieved label-free identification of up to 1,300 proteins from a single cell in a single run using an Orbitrap Fusion Lumos Mass Spectrometer coupled to either an Acquity UPLC M-class system or a Vanquish Neo UHPLC system. The developed sample processing workflow is highly reproducible, robust, and applicable to standardized 384- and 1536-well microplates, as well as glass LC vials. We demonstrate the applicability of the method for proteomics of single cells from multiple cell lines, mixed cell suspensions, and glioblastoma tumor spheroids. As additional proof of robustness, we monitored the results of genetic manipulations and the expression of engineered proteins in individual cells. Our cost-effective and robust single-cell proteomics workflow can be transferred to other labs interested in studying cells at the individual cell level. [ABSTRACT FROM AUTHOR]

Antimicrobial potential of bioactive glass (BAG) makes it promising for implant applications, specifically overcoming the toxicity concerns associated with traditional antibacterial nanoparticles. The 58S composition of BAG (with high Ca and absence of Na) has been known to exhibit excellent bioactivity and antibacterial behaviour, but the mechanisms behind have not been investigated in detail. In this pioneering study, we are using Atomic Force Microscopy (AFM) to gain insights into 58S BAG's adhesive interactions with planktonic cells of both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria; along with the impact of crystallinity on antibacterial properties. We have recorded greater bacterial inhibition by amorphous BAG compared to semi-crystalline glass–ceramics and stronger effect against gram-negative bacteria via conventional long-term antibacterial tests. AFM force distance curves has illustrated substantial bonding between bacteria and BAG within the initial one second (observed at a gap of 250 ms) of contact, with multiple binding events. Further, stronger adhesion of BAG with E.coli (~ 6 nN) compared to S. aureus (~ 3 nN) has been found which can be attributed to more adhesive nano-domains (size effect) distributed uniformly on E.coli surface. This study has revealed direct evidence of impact of contact time and 58S BAG's crystalline phase on bacterial adhesion and antimicrobial behaviour. Current study has successfully demonstrated the mode and mechanisms of initial bacterial adhesion with 58S BAG. The outcome can pave the way towards improving the designing of implant surfaces for a range of biomedical applications. [ABSTRACT FROM AUTHOR]

Glass and glass ceramics containing 40 wt.% of heavy metal oxides (Bi, Ta, and W) were obtained for use in medicine as radiosensitizers. The properties of the composites were studied in vitro, including the generation of secondary radiation, chemical solubility, and the variations in the pH of the medium during resorption. The results demonstrated that the secondary radiation indicators and pH value of the medium decreased in the order: W > Ta > Bi. Solubility indices decreased in the order: W > Bi > Ta. Despite the highest generation of secondary ionizing radiation, W-containing ceramics based on Bioglass 45S5 are unsuitable for in vivo use due to their rapid dissolution and high alkalization of the environment. [ABSTRACT FROM AUTHOR]

Long bone fracture fixation with various techniques, viz., internal fixation, external fixation, external coaptation has been adapted since long time in veterinary practice. Despite of such advancements complications like implant loosening, migration resulting in malunion, non-union and delayed union are being observed later on. Various biomaterials have been identified and used in fracture management to improve the implant stability by holding bone and implant in position, enhancing and accelerating the bone healing via callus formation. Bioglass and Polymethylmethacrylate (PMMA) bone cement are a few of the biomaterials being used in the veterinary orthopaedics. This study was conducted on clinical cases of long bone fracture repair in 12 dogs, divided equality into two groups. Group I dogs were treated with Locking Compression Plate with bioglass putty as filling agent at interfragmentary spaces, while those in Group II were treated with Locking Compression Plate with PMMA as filling agent at interfragmentary spaces. The bone formation and bone union scores were significantly improved at 15th, 30th and 60th day interval of observation in both the groups. There was no statistically significant difference in scores between two groups, yet the scores were found to be better in group I, which might be attributed to the osteostimulative and osteoconductive properties of bioglass bone cement. PMMA bone cement is non-biodegradable and has numerous potential uses, but has serious disadvantages due to its adverse effects also. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis and characterization of SiO2–CaO–P2O5–Na2O nanofiber bioglass (BG) tablets using cellulose nanofibers (CNFs) as a template and starch binders. Three types of tablets are prepared: sago starch binder tablets, xanthan gum binder tablets, and dry press tablets (used as a control). The tablets are investigated for their physicochemical structure, mechanical properties, in‐vivo bioactivity, and antibacterial efficiency using various characterization techniques such as Fourier transform infrared (FTIR), field emission scanning electron microscope (FESEM), XRD, ICP, etc. The results indicate the formation of a hydroxyapatite (HA) layer on the surface of the tablets after immersion in simulated body fluid (SBF) for 28 days, demonstrating their bioactivity. FESEM analysis reveals the formation of HA crystals with different morphologies, including oval‐shaped crystals in sago tablets and needle‐like crystals in xanthan tablets. The binder tablets exhibit higher Ca/P ratios compared to the press‐dried tablets. Among the binder tablets, sago starch tablets show superior mechanical properties. Additionally, the binder tablets display efficient antibacterial activity against Staphylococcus aureus and Escherichia coli bacteria. These findings highlight their potential as promising candidates for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

The surface pre-reacted glass ionomer (S-PRG) filler is a type of bioactive functional glass that releases six different ions. This study examined the effects of the S-PRG filler eluate on Streptococcus mutans in the presence of sucrose. In a solution containing S. mutans, the concentrations of BO33−, Al3+, Sr2+, and F− were significantly higher in the presence of the S-PRG filler eluate than in its absence (p < 0.001). The concentrations of these ions further increased in the presence of sucrose. Additionally, the S-PRG filler eluate significantly reduced glucan formation by S. mutans (p < 0.001) and significantly increased the pH of the bacterial suspension (p < 0.001). Bioinformatic analyses revealed that the S-PRG filler eluate downregulated genes involved in purine biosynthesis (purC, purF, purL, purM, and purN) and upregulated genes involved in osmotic pressure (opuAa and opuAb). At a low pH (5.0), the S-PRG filler eluate completely inhibited the growth of S. mutans in the presence of sucrose and significantly increased the osmotic pressure of the bacterial suspension compared with the control (p < 0.001). These findings suggest that ions released from the S-PRG filler induce gene expression changes and exert an inhibitory effect on S. mutans in the presence of sucrose. [ABSTRACT FROM AUTHOR]

This investigation aimed to study the effects of adding TiO 2 on many aspects of 1393-B3 glasses, including their physio-chemical, mechanical parameters, crystallization behaviour, in-vitro bioactivity, hemocompatibility, and cellular viability. Here, we replaced 1393 glass silica with boric oxide to determine a more effective alternative. 1393-B3 bioactive glasses having the general weight % composition (53-X) B 2 O 3 , 6 Na 2 O, 5 MgO, 20 CaO, 12 K 2 O, 4 P 2 O 5 , X TiO 2 (where X = 0, 1.0, 1.5, 2.0, and 2.5 %) were prepared using solid-state melt quenching method in platinum crucible at 1100 °C for 2 h in an electric furnace with air as furnace atmosphere. This research aimed to investigate the complete substitution of 1393 glass silica with boric oxide in order to get a reduced melting temperature forming 1393-B3. The objective was to develop a more energy-efficient and economical bioactive glass. Thermal analysis of the samples was obtained up to 700 °C. To evaluate the in-vitro bioactivity, the samples were immersed in simulated body fluid (SBF). These materials undergo XRD, FTIR, and SEM/EDAX analysis both before and after soaking in SBF. These characterization results show the presence of a hydroxyapatite (HA) layer forming on the samples of the bioactive glass surface. The haemolysis process performed on human blood shows its haemocompatibility result. To test these results for the human body. We performed cell proliferation and cell compatibility on the MG-63 cell line to see its effect on osteosarcoma patients. Density (2.31–2.48 gm/cm3), pH value (7.4–8.86), and mechanical parameters such as compressive strength (98–125 MPa), flexural strength (33–54), and elasticity are measured. As a result, physio-chemical, mechanical, biological properties and in-vitro bioactivity of these samples were obtained with increasing concentration of TiO 2 in 1393-B3 borate bioactive glass and found to increase with increasing concentration of TiO 2. [ABSTRACT FROM AUTHOR]

In this study, three-dimensional polycaprolactone (PCL)-based scaffolds with controlled pore architecture were fabricated from sol-gel-derived bioactive glass containing 2% mol Ag (BAG) via robocasting technique. This method was implemented due to its advantageous features, including its high reproducibility, versatility in shapes and sizes, and customizability. The Taguchi method was employed to determine the experimental parameters for preparing optimized printable BAG /PCL nanocomposite inks, with five groups of printable inks. The printed scaffolds were characterized by scanning electron microscopy, simultaneous thermal analysis, Fourier transforms infrared spectroscopy and X-ray diffraction. The heat-treated BAG nanopowder at 550 °C exhibited an average particle size diameter of less than 15 nm with a homogenous silver distribution without any additional phase. Based on SEM images of BAG /PCL nanocomposite scaffolds, the regularity of printed structure depends on the weight% of powder and PCL. The BAG75P30 and BAG65P50 with 65 and 75%wt of BAG powder possessed the best regular structures (microscopic rods and also the well-designed macropores, lumen about 500 μm) with higher porosity (61–64%). All the fabricated scaffolds provided acceptable cell viability according to the MTT assay. The cells cultured on BAG75P30, BAG65P40, and BAG65P50 showed the highest ALP activity compared to other groups. Also, these three groups represented significant antibacterial properties among the groups. The 3D-printed BAG /PCL nanocomposite scaffolds with macro and micropores in the structure can be a promising candidate for bone tissue engineering to promote tissue restoration due to their structure and also antibacterial properties resulting from silver in the composition. [ABSTRACT FROM AUTHOR]

The failure of bone regeneration has been considered as a serious problem that troubling patients for decades, most of which was resulted by the poor angiogenesis and chronic inflammation after surgery. Among multiple materials applied in the repair of bone defect, silicate bioceramics attracted researchers because of its excellent bioactivity. The purpose of this study was to detect the effect of specific bioactive glass ceramic (AP40, based on crystalline phases of apatite and wollastonite) on angiogenesis and the subsequent bone growth through the modulation of macrophages. Two groups were included in this study: control group (macrophages without any stimulation, denominated as Control) and AP40 group (macrophages incubated on AP40). This study investigated the effect of AP40 on macrophages polarization (RAW264.7) and angiogenesis in vitro and in vivo. Additionally, the changes of angiogenic ability regulated by macrophages were explored. AP40 showed excellent angiogenesis potential and the expression of CD31 was promoted through the modulation of macrophages toward M2 subtype. Additionally, the macrophages incubated on AP40 synthesized more PDGF‐BB comparing to macrophages without any stimulation, which contributed to the improved angiogenetic ability of human umbilical vein endothelial cells (HUVECs). Results of in vivo studies indicated increased bone ingrowth along the implants, which indicated the potential of bioceramics for bone defect repair clinically. [ABSTRACT FROM AUTHOR]