Bioglass Research Articles

ELECTROCHEMICAL EVALUATION OF TI45NB COATED WITH 63S BIOGLASS BY ELECTROPHORETIC DEPOSITION

In this study, analyses were carried out to investigate the structural, mechanical and electrochemical behaviors of untreated and bioglass (BG)-coated Ti45Nb materials. The samples were coated with a mixture of 63s BG powder and phosphate ester (PE) at concentrations of 0.2, 0.4, 0.8, and 1 g using the electrophoretic deposition (EPD) method. Then, the structural, mechanical, and electrochemical properties of the untreated and coated samples were determined and characterized by using X-ray diffraction (XRD) and scanning electron microscope (SEM) devices. It was concluded that the 0.2 g coating provided resistance to corrosion for the Ti45Nb material more effectively than the others did.

Molecular simulation and machine learning tools to predict bioglass modulus of elasticity

The structure-property relationship of bioactive glasses depends on costly synthesis and property tests. Quantitative models with predictive capacity, based on molecular simulation (MS), is an alternative to accelerate these developments. Here, we apply MS and machine learning (ML) to predict the modulus of elasticity and expand the test capacity on large scale, for the compositions around the bioactivity envelopes, for 45S5 bioglass (6 wt% P2O5) and also 4, 5 and 7 wt%. We validate a force field, and with a simulated database, we tested 4 different ML algorithms. Na2O has the greatest impact on the modulus of elasticity, followed by CaO. The 6% and 7% P2O5 diagrams showed more compositions with high values for the modulus of elasticity and bioactivity simultaneously. Considerations about convenience of use ML methods are also presented. This study demonstrates the potential of MS and ML techniques in decision-making for the synthesis of glasses with bioactivity.

Cobalt/Bioglass Nanoparticles Enhanced Dermal Regeneration in a 3-Layered Electrospun Scaffold.

Due to the multilayered structure of the skin tissue, the architecture of its engineered scaffolds needs to be improved. In the present study, 45s5 bioglass nanoparticles were selected to induce fibroblast proliferation and their protein secretion, although cobalt ions were added to increase their potency. A 3-layer scaffold was designed as polyurethane (PU) - polycaprolactone (PCL)/ collagen/nanoparticles-PCL/collagen. The scaffolds examined by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), tensile, surface hydrophilicity and weight loss. Biological tests were performed to assess cell survival, adhesion and the pattern of gene expression. The mechanical assay showed the highest young modulus for the scaffold with the doped nanoparticles and the water contact angle of this scaffold after chemical crosslinking of collagen was reduced to 52.34±7.7°. In both assessments, the values were statistically compared to other groups. The weight loss of the corresponding scaffold was the highest value of 82.35±4.3 % due to the alkaline effect of metal ions and indicated significant relations in contrast to the scaffold with non-doped particles and bare one (P value<0.05). Moreover, better cell expansion, greater cell confluence and a lower degree of toxicity were confirmed. The up-regulation of TGF β1 and VEGF genes introduced this scaffold as a better model for the fibroblasts commitment to a new skin tissue among bare and nondoped scaffold (P value<0.05). The 3-layered scaffold which is loaded with cobalt ions-bonded bioglass nanoparticles, is a better substrate for the culture of the fibroblasts.

Fabrication and in vitro evaluation of polyvinyl alcohol/bio-glass composite for potential wound healing applications

In this study, a novel composite is fabricated by incorporating Polyvinyl alcohol (PVA) and Bio-Glass (BG) via the freeze-thaw method. PVA pre-polymer is prepared in three different concentrations i.e. (2%, 5%, and 10%) by dissolving PVA powder in distilled water by using a hot plate magnetic stirrer at 80° C, and a constant concentration of BG i.e 2% is added into each PVA prepolymer. Total six specimens including (PVA (2%), PVA (5%), PVA (10%), PVA (2%)/BG (2%), PVA (5%)/BG (2%), and PVA (10%)/ BG (2%) were prepared in which pure PVA specimens acts as a control group. The physicochemical and mechanical properties of the specimens were examined. Various characterization tests such as scanning electron microscopy (SEM), swelling analysis, degradability analysis, hygroscopicity, pH sensitivity, tensile analysis, gel fraction test, water vapor transmission rate (WVTR), and, contact angle analysis were performed on the samples. SEM analysis showed that with the increase in PVA concentration, the material becomes smoother and more compact. Results from the current study showed that tensile strength, degradation rate, and get content are directly proportional to PVA concentration, while swelling capacity, pH sensitivity, hygroscopicity, WVTR, and hydrophilicity are inversely related to PVA concentration. Moreover, with the addition of BG, tensile strength, degradation rate, pH sensitivity, swelling capability, hydrophilicity, and, gel content of the specimens is increased, whereas, WVTR is decreased and, hygroscopicity remains unchanged. Furthermore, results from this study must be taken a step ahead &amp; biocompatibility must be tested to evaluate the biological performance.

Bioprinting of bioglass-alginate/carboxymethyl cellulose for bone tissue engineering

Bone regenerative medicine requires suitable substitutes that promote osteogenesis. Most of the bio-macromolecular hydrogels are promising because they are biocompatible and biodegradable, but their viscoelastic properties make them challenging to use, especially in 3D bioprinting applications. This study aimed to enhance the mechanical properties of a bone substitute made of bioprinted alginate, carboxymethyl cellulose, and 58S bioglass. We used dual cross-linking and optimized the concentration of cross-linking agents to improve hydrogel biological activity and mechanical stability. The compression test indicated that the combination of Ca2+ and Fe3+ significantly improved the mechanical properties of the alginate/carboxymethyl cellulose hydrogel. The hydrogel crosslinked with 4% Ca2+ and 1.5% Fe3+ showed the highest Young's modulus. The study also found that the hydrogel rigidity influenced cell proliferation capability during bioprinting, as observed in the cell viability results. At day 7, the cell viability of the bioprinted constructs cross-linked with 0.5% and 1% Fe3+ exhibited significant increases. Similarly, these groups also demonstrated the highest alkaline phosphatase (ALP) activity at the same time. Results suggested that cross-linking density and resultant rigidity achieved by optimal concentrations of Fe3+ have very significant effects on cell viability and osteogenesis.

Antibacterial Biomaterial Based on Bioglass Modified with Copper for Implants Coating.

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.

Bioactive Glass Modified with Zirconium Incorporation for Dental Implant Applications: Fabrication, Structural, Electrical, and Biological Analysis.

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.

Fabrication and In Vitro Biological Evaluation of Zirconia Ceramics with 58S Bioglass via Vacuum Pressure Infiltration for Dental Implant

Due to its excellent biocompatibility, high mechanical strength, and favorable aesthetic effects, zirconia ceramics is considered as a potential dental implant material. However, the biological inertness of zirconia results in a lack of osseointegration. Herein, a newly modified zirconia ceramic with 58S bioglass (BG) is fabricated via vacuum pressure infiltration method. The effects of BG sol infiltration time on the microstructure, phase composition, mechanical properties, mineralization ability, surface profile and roughness, ions release, protein adsorption, and cell behavior in vitro of zirconia ceramics are investigated. The zirconia ceramics have a micronano surface structure as well as active ions’ releasing ability, improving the osseointegration ability of it synergistically. Compared to unmodified zirconia ceramics, BG‐modified zirconia ceramics not only maintains excellent mechanical strength, but also can enhance the bioactivity, cell adhesion, spreading, and osteoblast differentiation. Besides, the results of q‐polymerase chain reaction show that BG‐modified zirconia ceramics can promote the expressions of osteogenesis‐related genes, including collagen type I (Col‐I), osteocalcin (OCN), osteopontin (OPN), and runt‐related transcription factor 2 (Runx2), compared to the control group. In summary, research suggests that BG bioactive zirconia ceramics can be a potential candidate for dental implant.

Galvanic Deposition of Calcium Phosphate/Bioglass Composite Coating on AISI 316L

Calcium phosphate/Bioglass composite coatings on AISI 316L were investigated with regard to their potential role as a beneficial coating for orthopedic implants. These coatings were realized by the galvanic co-deposition of calcium phosphate compounds and Bioglass particles. A different amount of Bioglass 45S5 was used to study its effect on the performance of the composite coatings. The morphology and chemical composition of the coatings were investigated before and after their aging in simulated body fluid. The coatings uniformly covered the AISI 316L substrate and consisted of a brushite and hydroxyapatite mixture. Both phases were detected using X-ray diffraction and Raman spectroscopy. Additionally, both analyses revealed that brushite is the primary phase. The presence of Bioglass was verified through energy-dispersive X-ray spectroscopy, which showed the presence of a silicon peak. During aging in simulated body fluid, the coating was subject to a dynamic equilibrium of dissolution/reprecipitation with total conversion in only the hydroxyapatite phase. Corrosion tests performed in simulated body fluid at different aging times revealed that the coatings made with 1 g/L of Bioglass performed best. These samples have a corrosion potential of −0.068V vs. Ag/AgCl and a corrosion current density of 8.87 × 10−7 A/cm2. These values are better than those measured for bare AISI 316L (−0.187 V vs. Ag/AgCl and 2.52 × 10−6 A/cm2, respectively) and remained superior to pure steel for all 21 days of aging. This behavior indicated the good protection of the coating against corrosion phenomena, which was further confirmed by the very low concentration of Ni ions (0.076 ppm) released in the aging solution after 21 days of immersion. Furthermore, the absence of cytotoxicity, verified through cell viability assays with MC3T3-E1 osteoblastic cells, proves the biocompatibility of the coatings.

A new 3D-printed polylactic acid-bioglass composite for bone tissue engineering induces angiogenesis in vitro and in ovo.

Large bone defects such as those that occur after trauma or resections due to cancer still are a challenge for surgeons. Main challenge in this area is to find a suitable alternative to the gold-standard therapy, which is highly risky, and a promising option is to use biomaterials manufactured by 3D printing. In former studies, we demonstrated that the combination of polylactic acid (PLA) and bioglass (BG) resulted in a stable 3D-printable material, and porous and finely structured scaffolds were printed. These scaffolds exhibited osteogenic and anti-inflammatory properties. This 3D-printed material fulfills most of the requirements described in the diamond concept of bone healing. However, the question remains as to whether it also meets the requirements concerning angiogenesis. Therefore, the aim of this study was to analyze the effects of the 3D-printed PLA-BG composite material on angiogenesis. In vitro analyses with human umbilical vein endothelial cells (HUVECs) showed a positive effect of increasing BG content on viability and gene expression of endothelial markers. This positive effect was confirmed by an enhanced vascular formation analyzed by Matrigel assay and chicken chorioallantoic membrane (CAM) assay. In this work, we demonstrated the angiogenic efficiency of a 3D-printed PLA-BG composite material. Recalling the osteogenic potential of this material demonstrated in former work, we manufactured a mechanically stable, 3D-printable, osteogenic and angiogenic material, which could be used for bone tissue engineering.

Physicochemical and histological analysis of an experimental endodontic repair material containing 45S5 bioactive glass.

This study aimed to evaluate the maximum compressive strength, the modulus of elasticity, pH variation, ionic release, radiopacity and biological response of an experimental endodontic repair cement based on 45S5 Bioglass®. An in vitro and in vivo study with an experimental endodontic repair cement containing 45S5 bioactive glass was conducted. There were three endodontic repair cement groups: 45S5 bioactive glass-based (BioG), zinc oxide-based (ZnO), and mineral trioxide aggregate (MTA). In vitro tests were used to evaluate their physicochemical properties: compressive strength, modulus of elasticity, radiopacity, pH variation, and the ionic release of Ca+ and PO4. An animal model was used to evaluate the bone tissue response to endodontic repair cement. Statistical analysis included the unpaired t-test, one-way ANOVA and Tukey's test. BioG showed the lowest compressive strength and ZnO showed the highest radiopacity among the groups, respectively (p < 0.05). There were no significant differences in the modulus of elasticity among the groups. BioG and MTA maintained an alkaline pH during the 7days of evaluation, both at pH 4 and in a pH 7 buffered solutions. PO4 was elevated in BioG, peaking at 7days (p < 0.05). Histological analysis showed less intense inflammatory reactions and new bone formation in MTA. BioG showed inflammatory reactions that decreased over time. These findings suggest that the BioG experimental cement had good physicochemical characteristics and biocompatibility required for bioactive endodontic repair cement.

SB216763-loaded multifunctional copper-doped bioglass 3D printed scaffold promotes wound healing and functional skin regeneration

Complete skin reconstruction is a complex process which involves regeneration and reconstruction of the epidermis, dermis, vascular system, nerves, hair follicles, and sweat glands. Multiple wound dressings have been developed for skin regeneration. However, only a few studies have focused on the regeneration of hair and skin appendages, particularly blood vessels and hair follicles. In this study, 3D printed Cu-doped 1393-2B bioglass (Cu-BG) with chitosan (CS) and 1393-2B bioglass (BG) with chitosan wound dressing (Cu-BG/CS, BG/CS) were designed. The swelling rate and mechanical and antibacterial properties of BG/CS and Cu-BG/CS wound dressings in different composites were compared. Cu-BG/CS exhibited antibacterial properties and vascular growth. Additionally, SB216763 was loaded onto Cu-BG/CS dressings, and it was observed that Cu-BG/[email protected] exhibited better proliferation ability and certain.

ПОЛУЧЕНИЕ ФУНКЦИОНАЛЬНЫХ СТЕКЛОКЕРАМИЧЕСКИХ МАТЕРИАЛОВ МЕТОДОМ ПИРОЛИЗА ОРГАНИЧЕСКИХ РАСТВОРОВ

The paper presents a method for the synthesis of functional glass-ceramic materials based on Bioglass 45S5 by pyrolysis of a mixture of organic solutions. Samples of bioglasses doped with zirconium(IV) and tantalum(V) oxides were obtained. The influence of doping on the properties of bioglasses was studied by the following methods: XRD, SEM, EDX. A change in the physical and chemical properties of Bioglass 45S5 with an increase in the content of a functional additive has been established. The obtained materials are promising for modern medicine and can be used to restore bone tissue, as well as to treat malignant neoplasms.

Rheological behaviour of different composite materials for additive manufacturing of 3D bone scaffolds

The production of scaffolds for bone tissue applications is requiring a combination of physical and biological properties, which are depending on the materials morphology and pro-cessing conditions during the production process. The aim of the paper is the investigation of rheological behaviour of polymer and composite blends regularly used for the production of scaffolds for bone tissue applications with the use of additive manufacturing. Poly-ε-caprolactone (PCL), hydroxyapatite (HA), β-tri-calcium phosphate (TCP) and Bioglass 45S5 blends containing different ceramic concentrations (10 wt%, 15 wt% and 20 wt%) were prepared with the use of melt blending procedure and investigated with the use of oscillation and rotational rheology tests. Results are showing that all blends are presenting viscoelastic behaviour with higher viscous modulus, compared with elastic modulus for low frequencies, with this difference reducing while the frequency is increasing. All blends are presenting shear-thinning behaviour suitable for use with additive manufacturing methods. Viscous and elastic modulus are increasing by adding ceramic particles. Results are presenting that PCL/HA blends of the same material concentration are presenting higher elastic modulus properties compared with the other blends, while PCL/Bioglass blends are presenting lower loss factor, lower relaxation time and lower shear viscosity making them easier to handle during the printing procedure.

Trends and perspectives on the commercialization of bioactive glasses.

At least 25 bioactive glass (BG) medical devices have been approved for clinical use by global regulatory agencies. Diverse applications include monolithic implants, bone void fillers, dentin hypersensitivity agents, wound dressing, and cancer therapeutics. The morphology and delivery systems of bioactive glasses have evolved dramatically since the first devices based on 45S5 Bioglass®. The particle size of these devices has generally decreased with the evolution of bioactive glass technology but primarily lies in the micron size range. Morphologies have progressed from glass monoliths to granules, putties, and cements, allowing medical professionals greater flexibility and control. Compositions of these commercial materials have primarily relied on silicate-based systems with varying concentrations of sodium, calcium, and phosphorus. Furthermore, therapeutic ions have been investigated and show promise for greater control of biological stimulation of genetic processes and increased bioactivity. Some commercial products have exploited the borate and phosphate-based compositions for soft tissue repair/regeneration. Mesoporous BGs also promise anticancer therapies due to their ability to deliver drugs in combination with radiotherapy, photothermal therapy, and magnetic hyperthermia. The objective of this article is to critically discuss all clinically approved bioactive glass products. Understanding essential regulatory standards and rules for production is presented through a review of the commercialization process. The future of bioactive glasses, their promising applications, and the challenges are outlined. STATEMENT OF SIGNIFICANCE: Bioactive glasses have evolved into a wide range of products used to treat various medical conditions. They are non-equilibrium, non-crystalline materials that have been designed to induce specific biological activity. They can bond to bone and soft tissues and contribute to their regeneration. They are promising in combating pathogens and malignancies by delivering drugs, inorganic therapeutic ions, and heat for magnetic-induced hyperthermia or laser-induced phototherapy. This review addresses each bioactive glass product approved by regulatory agencies for clinical use. A review of the commercialization process is also provided with insight into critical regulatory standards and guidelines for manufacturing. Finally, a critical evaluation of the future of bioactive glass development, applications, and challenges are discussed.

Gallic acid-modified bioglass with combined photothermal and antibacterial effects for the regeneration of infected diabetic wound

Diabetes-associated chronic wound management has been a serious worldwide issue, which is obstructed by multiple factors such as sustained inflammation, attenuated angiogenesis, and fragile defense against bacterial infection in the wound niche. Thus, there stands an urgent demand for biomaterial dressings that are able to treat such complex conditions. Herein, we developed a composite biomaterial of gallic acid-modified bioglass (GA@BG) in an anhydrous system, by using two agents which have already been used in clinical practice. The prepared GA@BG not merely promoted the migration and angiogenesis of vascular endothelial cells but also provided superior antibacterial performance in the local environment. Significantly, the gallic acid-assisted modification made the color of bioglass (BG) change from white to black, endowing it with high light absorption to successfully achieve a significant photothermal property. Then, the strengthened antibacterial effects were further realized by irradiation with near-infrared light (NIR) based on this photothermal property. Particularly, the combined therapy (GA@BG + NIR) was demonstrated as an effective strategy in treating the infected full-thickness dermal wounds of diabetic rats. This research provides a convenient non-antibiotic medicine formula for diabetic wounds with infection, and demonstrates a valid modification for inorganic bioglass-based material with organic polyphenol, which inspires more expansive composites for wound biomaterials.

Extensive Investigation on the Effect of Niobium Insertion on the Physical and Biological Properties of 45S5 Bioactive Glass for Dental Implant

Dental implants have emerged as one of the most consistent and predictable treatments in the oral surgery field. However, the placement of the implant is sometimes associated with bacterial infection leading to its loss. In this work, we intend to solve this problem through the development of a biomaterial for implant coatings based on 45S5 Bioglass® modified with different amounts of niobium pentoxide (Nb2O5). The structural feature of the glasses, assessed by XRD and FTIR, did not change in spite of Nb2O5 incorporation. The Raman spectra reveal the Nb2O5 incorporation related to the appearance of NbO4 and NbO6 structural units. Since the electrical characteristics of these biomaterials influence their osseointegration ability, AC and DC electrical conductivity were studied by impedance spectroscopy, in the frequency range of 102-106 Hz and temperature range of 200-400 K. The cytotoxicity of glasses was evaluated using the osteosarcoma Saos-2 cells line. The in vitro bioactivity studies and the antibacterial tests against Gram-positive and Gram-negative bacteria revealed that the samples loaded with 2 mol% Nb2O5 had the highest bioactivity and greatest antibacterial effect. Overall, the results showed that the modified 45S5 bioactive glasses can be used as an antibacterial coating material for implants, with high bioactivity, being also non-cytotoxic to mammalian cells.

In-vivo evaluations of bone regenerative potential of two novel bioactive glasses.

Due to the aging of population, materials able to repair damaged tissues are needed. Among others, bioactive glasses (BGs) have attracted a lot of interest due to their outstanding properties both for hard and soft tissues. Here, for the first time, two new BGs, which gave very promising results in preliminary in vitro-tests, were implanted in animals in order to evaluate their regenerative potential. The new BGs, named BGMS10 and Bio_MS and containing specific therapeutic ions, were produced in granules and implanted in rabbits' femurs for up to 60 days, to test their biocompatibility and osteoconduction. Additionally, granules of 45S5 Bioglass® were employed and used as a standard reference for comparison. The results showed that, after 30 days, the two novel BGs and 45S5 displayed a similar behavior, in terms of bone amount, thickness of new bone trabeculae and affinity index. On the contrary, after 60 days, 45S5 granules were mainly surrounded by wide and scattered bone trabeculae, separated by large amounts of soft tissue, while in BGMS10 and Bio_MS the trabeculae were thin and uniformly distributed around the BG granules. This latter scenario could be considered as more advantageous, since the features of the two novel BG granules allowed for the neo-formation of a uniformly distributed bony trabeculae, predictive of more favorable mechanical behavior, compared to the less uniform coarse trabeculae, separated by large areas of soft tissue in 45S5 granules. Thus, BGMS10 and Bio_MS could be considered suitable products for tissue regeneration in the orthopedic and dental fields.

A novel rapidly mineralized biphasic calcium phosphate with high acid-resistance stability for long-term treatment of dentin hypersensitivity.

Treating dental hypersensitivity (DH) rapidly and maintaining long-term effectiveness remains challenging. We aimed to address this problem by fabricating a novel rapidly mineralized biphasic calcium phosphate (RMBCP), which could rapidly elicit mineralization to form hydroxyapatite (HA) and perform excellent acid-resistant stability, thus effectively blocking the exposed dental tubules and protecting them from acid attack. RMBCP was firstly synthesized by precisely adjusting the molar ratio of acetic acid and calcium hydroxide and characterized by X-ray diffraction (XRD), X-ray fluorescence microprobe (XRF), Fourier-transform infrared (FTIR) spectrometer, scanning electron microscope (SEM), and transmission electron microscope (TEM). Subsequently, using a commercialized desensitizing agent, 45S5 bioglass (BG), as the control group, the mineralization performance of RMBCP was investigated in simulated body fluid (SBF), Dulbecco's modified eagle medium (DMEM), and even slightly acidic artificial saliva (pH=6.6). Moreover, the biocompatibility of RMBCP was studied. Finally, the tubule occlusion effect and acid-resistant stability of RMBCP were evaluated in vitro and in vivo. The rapid mineralization behavior of RMBCP could easily adhere to the dentin surface and block the dentinal tubules completely in vitro and in vivo within 7days. RMBCP performed high acid-resistant stability to maintain the long-term therapeutic effect of DH treatment. Developing novel bioactive calcium phosphate materials with the ability to trigger mineralization for HA formation rapidly will be an effective strategy for the long-term treatment of dentin hypersensitivity.

Nanostructured 3D bioprinting of PLA with bioglass-CNT scaffolds for osseus tissue graft manufacturing

Bone involvement promoted by aging and accidents has raised interest in biomaterials and biofabrication technologies for bone regeneration purposes. Thus, 3D printing technology has gained prominence in the production of scaffolds due to its versatility in producing complex geometries with interconnected pores. In this work, composite scaffolds of poly (lactic acid) (PLA), bioglass (BG) and carbon nanotubes (CNT) were produced by 3D printing, using hexagonal, honeycomb-like geometry interspersed. The samples were analyzed in terms of chemical structure, crystallinity and morphology using Fourier transform infrared spectroscopy and Raman spectroscopy, X-ray diffraction and scanning electron microscopy, respectively. The thermal stability of the composite was evaluated by thermogravimetry and the mechanical properties by compression tests. The cell viability was determined by Alamar Blue. The results that raman spectroscopy confirmed the interaction of BG in the polymer matrix by new peaks in the spectrum between 1400 and 2600 cm−1 and the presence of the D, G and 2D bands of the CNTs. In terms of compressive strength, PLA scaffolds with 2 mm inner spacing demonstrated higher compressive strength of 14.88 ± 2.35 MPa, while PLA/CNT higher apparent compressive modulus of 0.58 ± 0.36 GPa. In cell viability, statistical tests showed that there was no significant difference between scaffolds with 2 and 4 mm inner spacing.