Search Results (20)

Bioactive glasses are known for their surface reactivity and ability to bond with bone tissue through the formation of hydroxyapatite. This study investigates the effects of substituting ultrapure water with natural geothermal waters from the Azores in the sol–gel synthesis of 45S5 and MgO-modified bioglasses. Using high-resolution X-ray photoelectron spectroscopy (XPS), we examined how the mineral composition of the waters influenced the chemical environment and network connectivity of the glass surface. The presence of trace ions, such as Mg²⁺, Sr²⁺, Zn²⁺, and B³⁺, altered the silicate structure, as evidenced by binding energy shifts and peak deconvolution in O 1s, Si 2p, P 2p, Ca 2p, and Na 1s spectra. Thermal treatment further promoted polymerization and reduced hydroxylation. Our findings suggest that mineral-rich waters act as functional agents, modulating the reactivity and structure of bioactive glass surfaces in eco-sustainable synthesis routes. Full article

This research activity proposes to produce composite hydrogel–bioactive glass. The primary purpose of this research is to develop and optimize 3D-printed scaffolds using doped bioglass, aimed at enhancing bone regeneration in bone defects. The bioglass, a bioactive material known for its bone-bonding ability (SiO₂–P₂O₅–CaO–Na₂O), co-doped with europium and silver was synthesized and doped to improve its biological properties. This doped bioglass was then combined with a biocompatible hydrogel, chosen for its adequate cellular response and printability. The composite material was printed to form a scaffold, providing a structure that not only supports the damaged bone but also encourages osteogenesis. A variety of methods were employed to assess the rheological, compositional, and morphological characteristics of the samples: Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). Additionally, simulated body fluid (SBF) immersion for bioactivity monitoring and immunocytochemistry for cell viability were used to evaluate the biological response of the scaffolds. Full article

Bioactive glasses in the SiO₂-CaO-P₂O₅ system represent emerging materials for hard-tissue-regeneration applications. This article focuses on the synthesis, characterization, and biological interaction of glasses doped with Mg²⁺ and/or Zn²⁺, with an emphasis on their effects on biomineralization, antibacterial behavior, and interactions with preosteoblasts from the MC3T3-E1 cell line. The bioglasses were synthesized using the sol-gel method, and the vitreous nature remained predominant even after thermal treatment at 600 °C for 2 h. From an in vitro perspective, the synthesized bioglasses demonstrated strong cell adhesion and proliferation (notably in the case of Mg²⁺ doping), low cytotoxicity, and antibacterial properties (especially in Zn²⁺-doped samples). Additionally, the simultaneous doping with Mg²⁺ and Zn²⁺ of the bioactive glass matrix is a prospective strategy for developing biomaterials with a “dual” biological characteristics–both osteoinductive and antibacterial. Full article

Multicomponent oxide systems have many applications in different fields such as optics and medicine. In this work, we developed new hybrid photoresists based on a combination of an organic acrylate resin and an inorganic sol, suitable for 3D printing via two-photon polymerization (2PP). The inorganic sol contained precursors of a binary SiO₂-CaO or a ternary SiO₂-CaO-P₂O₅ system. Complex microstructures were 3D printed using these hybrid photoresists and 2PP. The obtained materials were characterized using thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) techniques. Our results revealed that the produced microstructures were able to endure sintering at 700 °C without collapsing, leading to scaffolds with 235 and 355 nm resolution and pore size, respectively. According to the TGA analysis, there was no significant mass loss beyond 600 °C. After sintering at 500 °C, the FTIR spectra showed the disappearance of the characteristic bands associated with the organic phase, and the presence of bands characteristic of the binary and ternary oxide systems and carbonate groups. The SEM images showed different morphologies of agglomerated nanoparticles with mean sizes of about 20 and 60 nm for ternary and binary systems, respectively. Our findings open the way towards precise control of bioglass scaffold fabrication with tremendous design flexibility. Full article

In recent decades, the requirements for implantable medical devices have increased, but the risks of implant rejection still exist. These issues are primarily associated with poor osseointegration, leading to biofilm formation on the implant surface. This study focuses on addressing these issues by developing a biomaterial for implant coatings. 45S5 bioglass^® has been widely used in tissue engineering due to its ability to form a hydroxyapatite layer, ensuring a strong bond between the hard tissue and the bioglass. In this context, 45S5 bioglasses^®, modified by the incorporation of different amounts of copper oxide, from 0 to 8 mol%, were synthesized by the melt–quenching technique. The incorporation of Cu ions did not show a significant change in the glass structure. Since the bioglass exhibited the capacity for being polarized, thereby promoting the osseointegration effectiveness, the electrical properties of the prepared samples were studied using the impedance spectroscopy method, in the frequency range of 10²–10⁶ Hz and temperature range of 200–400 K. The effects of CuO on charge transport mobility were investigated. Additionally, the bioactivity of the modified bioglasses was evaluated through immersion tests in simulated body fluid. The results revealed the initiation of a Ca–P-rich layer formation on the surface within 24 h, indicating the potential of the bioglasses to enhance the bone regeneration process. Full article

Because of the physiological and cardiac changes associated with cardiovascular disease, tissue engineering can potentially restore the biological functions of cardiac tissue through the fabrication of scaffolds. In the present study, hybrid nanofiber scaffolds of poly (vinyl alcohol) (PVA) and bioglass type 58S (58SiO₂-33CaO-9P₂O₅, Bg) were fabricated, and their effect on the spontaneous activity of chick embryonic cardiomyocytes in vitro was determined. PVA/Bg nanofibers were produced by electrospinning and stabilized by chemical crosslinking with glutaraldehyde. The electrospun scaffolds were analyzed to determine their chemical structure, morphology, and thermal transitions. The crosslinked scaffolds were more stable to degradation in water. A Bg concentration of 25% in the hybrid scaffolds improved thermal stability and decreased degradation in water after PVA crosslinking. Cardiomyocytes showed increased adhesion and contractility in cells seeded on hybrid scaffolds with higher Bg concentrations. In addition, the effect of Ca²⁺ ions released from the bioglass on the contraction patterns of cultured cardiomyocytes was investigated. The results suggest that the scaffolds with 25% Bg led to a uniform beating frequency that resulted in synchronous contraction patterns. Full article

The non-surgical treatments are being required to reconstruct damaged tissue, prioritizing our body’s natural healing process. Thus, the use of bioactive materials such as bioactive glass has been studied to support the repair and restoration of hard and soft tissue. Thus, in this work Bioglass 45S5 was developed, adding 1 and 2%mol of SrO or MgO and the physical and biological properties were evaluated. The addition of MgO and SrO at the studied concentrations promoted the slight increase in non-bridging oxygens number, observed through the temperature shift in phase transitions to lower values compared to Bioglass 45S5. The insertion of the ions also showed a positive effect on Saos-2 cell viability, decreasing the cytotoxic of Bioglass 45S5. Besides the Ca/P ratio on the pellets surface demonstrating no evidence of higher reactivity between Bioglass 45S5 and Bioglass with Sr and Mg, micrographs show that at 24 h the Ca/P rich layer is denser than in Bioglass 45S5 after the contact with simulated body fluid. The samples with Sr and Mg show a higher antibacterial effect compared to Bioglass 45S5. The addition of the studied ions may benefit the biological response of Bioglass 45S5 in dental applications as scaffolds or coatings. Full article

The development of innovative biomaterials with improved integration with bone tissue and stimulating regeneration processes is necessary. Here, we evaluate the usefulness of bioactive glasses from the SiO₂-P₂O₅-CaO system enriched with 2 wt.% SrO or ZnO in the manufacturing of chitosan-based scaffolds. Bioglasses produced using the sol-gel method were subjected to thermal treatment in different regimes. Chitosan/bioglass composites were produced with a weight ratio. Bioglasses were evaluated via TG-DTA, FTIR, and SEM-EDS before and after incubation in simulated body fluid (SBF). The release of ions was tested. The cytocompatibility of the composites in contact with MG63 osteoblast-like cells was evaluated. The results showed that the presence of the crystalline phase decreased from 41.2–44.8% for nonmodified bioglasses to 24.2–24.3% for those modified with ZnO and 22.0–24.2% for those modified with SrO. The samples released Ca²⁺, Zn²⁺, and/or Sr²⁺ ions and were bioactive according to the SBF test. The highest cytocompatibility was observed for the composites containing nonmodified bioglasses, followed by those enriched with SrO bioglasses. The least cytocompatible were the composites containing ZnO bioglasses that released the highest amount of Zn²⁺ ions (0.58 ± 0.07 mL/g); however, those that released 0.38 ± 0.04 mL/g were characterised by acceptable cytocompatibility. The study confirmed that it is feasible to control the biological performance of chitosan/bioglass composites by adjusting the composition and heat treatment parameters of bioglasses. Full article

Calcium phosphate materials and materials based on silicon dioxide have been actively studied for more than 50 years due to their high biocompatibility and bioactivity. Hydroxyapatite and tricalcium phosphate are the most known among calcium phosphate materials, and Bioglass 45S5 is the most known material in the Na₂O–CaO–SiO₂–P₂O₅ system. Each of these materials has its application limits; however, some of them can be eliminated by obtaining composites based on calcium phosphate and bioglass. In this article, we provide an overview of the role of silicon and its compounds, including Bioglass 45S5, consider calcium phosphate materials, talk about the limits of each material, demonstrate the potential of the composites based on them, and show the other ways of obtaining composite ceramics in the Na₂O–CaO–SiO₂–P₂O₅ system. Full article

Biofilm-related implant infections pose a substantial threat to patients, leading to inflammation in the surrounding tissue, and often resulting in implant loss and the necessity for additional surgeries. Overcoming this implantology challenge is crucial to ensure the success and durability of implants. This study shows the development of antibacterial materials for implant coatings by incorporating copper into 45S5 Bioglass^®. By combining the regenerative properties of Bioglass^® with the antimicrobial effects of copper, this material has the potential to prevent infections, enhance osseointegration and improve the long-term success of implants. Bioglasses modified with various concentrations of CuO (from 0 to 8 mol%) were prepared with the melt-quenching technique. Structural analysis using Raman and FTIR spectroscopies did not reveal significant alterations in the bioglasses structure with the addition of Cu. The antibacterial activity of the samples was assessed against Gram-positive and Gram-negative bacteria, and the results demonstrated significant inhibition of bacterial growth for the bioglass with 0.5 mol% of CuO. Cell viability studies indicated that the samples modified with up to 4 mol% of CuO maintained good cytocompatibility with the Saos-2 cell line at extract concentrations up to 25 mg/mL. Furthermore, the bioactivity assessment demonstrated the formation of a calcium phosphate (CaP)-rich layer on the surfaces of all bioglasses within 24 h. Our findings show that the inclusion of copper in the bioglass offers a significant enhancement in its potential as a coating material for implants, resulting in notable advancements in both antibacterial efficacy and osteointegration properties. Full article

Implantology is crucial for restoring aesthetics and masticatory function in oral rehabilitation. Despite its advantages, certain issues, such as bacterial infection, may still arise that hinder osseointegration and result in implant rejection. This work aims to address these challenges by developing a biomaterial for dental implant coating based on 45S5 Bioglass^® modified by zirconium insertion. The structural characterization of the glasses, by XRD, showed that the introduction of zirconium in the Bioglass network at a concentration higher than 2 mol% promotes phase separation, with crystal phase formation. Impedance spectroscopy was used, in the frequency range of 10²–10⁶ Hz and the temperature range of 200–400 K, to investigate the electrical properties of these Bioglasses, due to their ability to store electrical charges and therefore enhance the osseointegration capacity. The electrical study showed that the presence of crystal phases, in the glass ceramic with 8 mol% of zirconium, led to a significant increase in conductivity. In terms of biological properties, the Bioglasses exhibited an antibacterial effect against Gram-positive and Gram-negative bacteria and did not show cytotoxicity for the Saos-2 cell line at extract concentrations up to 25 mg/mL. Furthermore, the results of the bioactivity test revealed that within 24 h, a CaP-rich layer began to form on the surface of all the samples. According to our results, the incorporation of 2 mol% of ZrO₂ into the Bioglass significantly improves its potential as a coating material for dental implants, enhancing both its antibacterial and osteointegration properties. Full article

The main reason for the increased use of dental implants in clinical practice is associated with aesthetic parameters. Implants are also presented as the only technique that conserves and stimulates natural bone. However, there are several problems associated with infections, such as peri-implantitis. This disease reveals a progressive inflammatory action that affects the hard and soft tissues surrounding the implant, leading to implant loss. To prevent the onset of this disease, coating the implant with bioactive glasses has been suggested. In addition to its intrinsic function of promoting bone regeneration, it is also possible to insert therapeutic ions, such as cerium. Cerium has several advantages when the aim is to improve osseointegration and prevent infectious problems with dental implant placement. It promotes increased growth and the differentiation of osteoblasts, improves the mechanical properties of bone, and prevents bacterial adhesion and proliferation that may occur on the implant surface. This antibacterial effect is due to its ability to disrupt the cell wall and membrane of bacteria, thus interfering with vital metabolic functions such as respiration. In addition, its antioxidant effect reverses oxidative stress after implantation in bone. In this work, Bioglass 45S5 with CeO₂ with different percentages (0.25, 0.5, 1, and 2 mol%) was developed by the melt-quenching method. The materials were analyzed in terms of morphological, structural, and biological (cytotoxicity, bioactivity, and antibacterial activity) properties. The addition of cerium did not promote structural changes to the bioactive glass, which shows no cytotoxicity for the Saos-2 cell line up to 25 mg/mL of extract concentration for all cerium contents. For the maximum cerium concentration (2 mol%) the bioactive glass shows an evident inhibitory effect for Escherichia coli and Streptococcus mutans bacteria. Furthermore, all samples showed the beginning of the deposition of a CaP-rich layer on the surface of the material after 24 h. Full article

This study aimed to assess bioglass sintering to a zirconia core on surface properties and bonding strength to resin cement. Zirconia specimens were divided into four groups: G I: sintered; G II: bioglass modified zirconia (a bioglass slurry was sintered with zirconia at 1550 °C); G III: sandblasted using 50 μm Al₂O₃ particles; and G IV: Z-prime plus application. Surface morphology and chemical analysis were studied using a scanning electron microscope and energy-dispersive spectroscopy. Surface roughness was evaluated using a profilometer. Surface hardness was measured using an indentation tester. For the microshear bond strength test, resin cement cylinders were bonded to a zirconia surface. Half of the specimens were tested after 24 h; the other half were thermocycled (5–55 °C) for 1000 cycles. A shearing load was applied at a crosshead speed of 0.5 mm/min on a universal testing machine. Data were analyzed with ANOVA using SPSS software at (p < 0.05). Results: tThe mean surface roughness of G II was significantly higher than G I and G III. The microhardness of G II was significantly lower than all groups. For bond strength, there was no significant difference between groups II, III, and IV after thermocycling. Conclusions: Bioactive glass can increase the bond strength of zirconia to resin cement, and is comparable to sandblasting and Z-prime bonding agents. Full article

Bioglass (BG) is a class of biomaterials increasingly approached in biomedical applications, such as in regeneration of hard tissues, due to the properties of bioactivity, osteoinductivity, osteoconductivity, but also the high rate of biodegradation, both in vitro and in vivo. The present paper addresses the obtaining of bioglasses from the ZnO(MgO)-CaO-SiO₂-P₂O₅ system by the sol-gel method and the use of a surfactant to ensure a specific surface or high open porosity, starting from S53P4 bioglass (53% SiO₂, 23% Na₂O, 20% CaO, 4% P₂O₅), also known as BoneAlive^®. The precursor powders were analyzed from the phase composition point of view by complex thermal analysis and X-ray diffraction, the vitreous powders were assessed from the compositional point of view by X-ray diffraction, morpho-structural by scanning electron microscopy, specific surface area and the pore size dimension by the Brunauer–Emmett–Teller (BET) analysis, dispersion by laser granulometry, and also cell biology and surface mineralization tests were performed by immersion in SBF (simulated body fluid). The system proposed in this paper ZnO(MgO)-CaO-SiO₂-P₂O₅ was successfully obtained by sol-gel method. The results showed the higher interaction between the samples and the SBF medium for samples containing magnesium (M2) and the lowest degree of mineralization after immersion in SBF was noticed for samples containing zinc (M1). The results also prove that by incorporating different ionic species in bioglass composition—Zn²⁺ and Mg²⁺, biocompatibility and antibacterial properties will be significantly enhanced. Full article

Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for bone and dental repair and regeneration implants. In the present study, a 8ZnO–22Na₂O–(24 − x)CaO–46P₂O₅–xZrO₂ (0.1 ≤ x ≤ 0.7, all are in mol%) bioglass system was synthesized by the conventional melt-quenching process at 1100 °C. The glass-forming ability and thermal stability of the glasses were determined by measuring the glass transition temperature (T_g), crystallization temperature (T_c), and melting temperature (T_m), using differential thermal analysis (DTA). The biological activity of the prepared samples was identified by analyzing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy-energy dispersive spectra (SEM-EDS), before and after immersion in simulated body fluid (SBF) for various intervals of 0, 1 and 5 days, along with the magnitude of pH and the degradation of glasses also evaluated. The obtained results revealed that the glass-forming ability and thermal stability of glasses increased with the increase in zirconia mol%. The XRD, FTIR, and SEM-EDS data confirmed a thin hydroxyapatite (HAp) layer over the sample surface after incubation in SBF for 1 and 5 days. Furthermore, the development of layer found to be increased with the increase of incubation time. The degradation of the glasses in SBF increased with incubation time and decreased gradually with the increase content of ZrO₂ mol% in the host glass matrix. A sudden rise in initial pH values of residual SBF for 1 day owing to ion leaching and increase of Ca²⁺ and PO₄³⁻ ions and then decreased. These findings confirmed the suitability of choosing material for bone-related applications. Full article