Injectable Osteoinductive bone cements

The present invention concerns an injectable composition for the use in bone-filling and bone-consolidation in surgery and therapy. In particular, the invention relates to the field of injectable bone cements, for both treating of factures caused by osteoporosis or trauma and filling gaps due, for example, to the decrease of bone mass after removal of tumors or cysts

3D printed hybrid scaffolds for bone regeneration using calcium methoxyethoxide as a calcium source

Introduction: Hybrids consist of inorganic and organic co-networks that are indistinguishable above the nanoscale, which can lead to unprecedented combinations of properties, such as high toughness and controlled degradation. Methods: We present 3D printed bioactive hybrid scaffolds for bone regeneration, produced by incorporating calcium into our "Bouncy Bioglass", using calcium methoxyethoxide (CME) as the calcium precursor. SiO2-CaOCME/PTHF/PCL-diCOOH hybrid "inks" for additive manufacturing (Direct Ink Writing) were optimised for synergy of mechanical properties and open interconnected pore channels. Results and Discussion: Adding calcium improved printability. Changing calcium content (5, 10, 20, 30, and 40 mol.%) of the SiO2-CaOCME/PTHF/PCL-diCOOH hybrids affected printability and mechanical properties of the lattice-like scaffolds. Hybrids containing 30 mol.% calcium in the inorganic network (70S30CCME-CL) printed with 500 µm channels and 100 µm strut size achieved the highest strength (0.90 ± 0.23 MPa) and modulus of toughness (0.22 ± 0.04 MPa). These values were higher than Ca-free SiO2/PTHF/PCL-diCOOH hybrids (0.36 ± 0.14 MPa strength and 0.06 ± 0.01 MPa toughness modulus). Over a period of 90 days of immersion in simulated body fluid (SBF), the 70S30CCME-CL hybrids also kept a stable strain to failure (~30 %) and formed hydroxycarbonate apatite within three days. The extracts released by the 70S30CCME-CL hybrids in growth medium did not cause cytotoxic effects on human bone marrow stromal cells over 24 h of culture

Zirconia-containing radiopaque mesoporous bioactive glasses

cited By 13International audienceA radiopaque mesoporous bioactive glass (named MBGZ-7) was obtained through a combined sol-gel and evaporation induced self-assembling (EISA) route, adding zirconium propoxide to the synthesis batch as the zirconia precursor. The nitrogen sorption analysis confirmed the mesoporous nature of the glass. The assessment of in vitro bioactivity by soaking in acellular simulated body fluid (SBF) and SEM observation showed the deposition of hydroxyapatite crystals on its surface after one week. The good radiopacity level was demonstrated by comparing X-ray images of MBGZ-7 and a blank sample that did not contain radiopaque additives. It is envisaged the use of MBGZ-7 as a promising dispersed phase in composite materials for minimally invasive surgery procedures, such as injectable bone cements, in order to allow the visualization of the implant under fluoroscopic control, during both injection and follow-up. © 2014 Elsevier B.V

Hyaluronic acid hydrogels reinforced with laser spun bioactive glass micro- and nanofibres doped with lithium

The repair of articular cartilage lesions in weight-bearing joints remains as a significant challenge due to the low regenerative capacity of this tissue. Hydrogels are candidates to repair lesions as they have similar properties to cartilage extracellular matrix but they are unable to meet the mechanical and biological requirements for a successful outcome. Here, we reinforce hyaluronic acid (HA) hydrogels with 13-93-lithium bioactive glass micro- and nanofibres produced by laser spinning. The glass fibres are a reinforcement filler and a platform for the delivery of therapeutic lithium-ions. The elastic modulus of the composites is more than three times higher than in HA hydrogels. Modelling of the reinforcement corroborates the experimental results. ATDC5 chondrogenic cells seeded on the composites are viable and more proliferation occurs on the hydrogels containing fibres than in HA hydrogels alone. Furthermore, the chondrogenic behavior on HA constructs with fibres containing lithium is more marked than in hydrogels with no-lithium fibres.Xunta de Galicia | Ref. ED431B 2016/042Xunta de Galicia | Ref. POS-A/2013/161Xunta de Galicia | Ref. ED481D 2017/010Xunta de Galicia | Ref. ED481B 2016/047-

3D printed hybrid scaffolds for bone regeneration using calcium methoxyethoxide as a calcium source

Introduction: Hybrids consist of inorganic and organic co-networks that are indistinguishable above the nanoscale, which can lead to unprecedented combinations of properties, such as high toughness and controlled degradation.Methods: We present 3D printed bioactive hybrid scaffolds for bone regeneration, produced by incorporating calcium into our “Bouncy Bioglass”, using calcium methoxyethoxide (CME) as the calcium precursor. SiO2-CaOCME/PTHF/PCL-diCOOH hybrid “inks” for additive manufacturing (Direct Ink Writing) were optimised for synergy of mechanical properties and open interconnected pore channels.Results and Discussion: Adding calcium improved printability. Changing calcium content (5, 10, 20, 30, and 40 mol.%) of the SiO2-CaOCME/PTHF/PCL-diCOOH hybrids affected printability and mechanical properties of the lattice-like scaffolds. Hybrids containing 30 mol.% calcium in the inorganic network (70S30CCME-CL) printed with 500 µm channels and 100 µm strut size achieved the highest strength (0.90 ± 0.23 MPa) and modulus of toughness (0.22 ± 0.04 MPa). These values were higher than Ca-free SiO2/PTHF/PCL-diCOOH hybrids (0.36 ± 0.14 MPa strength and 0.06 ± 0.01 MPa toughness modulus). Over a period of 90 days of immersion in simulated body fluid (SBF), the 70S30CCME-CL hybrids also kept a stable strain to failure (~30 %) and formed hydroxycarbonate apatite within three days. The extracts released by the 70S30CCME-CL hybrids in growth medium did not cause cytotoxic effects on human bone marrow stromal cells over 24 h of culture

Bioactive glass-derived trabecular coating: a smart solution for enhancing osteointegration of prosthetic elements

In this work, the use of foam-like glass-ceramic scaffolds as trabecular coatings on ceramic prosthetic devices to enhance implant osteointegration is proposed. The feasibility of this innovative device was explored in a simplified, flat geometry: glass-ceramic scaffolds, prepared by polymeric sponge replication and mimicking the trabecular architecture of cancellous bone, were joined to alumina square substrates by a dense glass coating (interlayer). The role played by different formulations of starting glasses was examined, with particular care to the effect on the mechanical properties and bioactivity of the final coating. Microindentations at the coating/substrate interface and tensile tests were performed to evaluate the bonding strength between the sample's components. In vitro bioactive behaviour was assessed by soaking in simulated body fluid and evaluating the apatite formation on the surface and inside the pores of the trabecular coating. The concepts disclosed in the present study can have a significant impact in the field of implantable devices, suggesting a valuable alternative to traditional, often invasive bone-prosthesis fixatio

3-D printed flexible hybrids for tissue regeneration

Tissue regeneration is a key function of the body, but often tissues are subject to damage that they are unable to self-heal. The repair can be supported by a scaffold, which is commonly a 3D porous temporary template that substitutes the damaged tissue and guides the growth of healthy tissue while bioresorbing. Successful scaffolds should satisfy several requirements, including interconnected porosity, sufficient mechanical properties, and biodegradability at a rate matching tissue regrowth. Covalently-bonded sol-gel inorganic/organic hybrids are interpenetrating co-networks of bioactive glass and polymers intimately linked at the molecular level, designed to provide tailored mechanical properties and congruent degradation. This project aimed to develop new silica/polycaprolactone (SiO2/PCL) hybrid scaffolds for bone or cartilage regeneration. The covalent bond between PCL and silica was successfully achieved using (3-glycidoxypropyl)trimethoxysilane (GPTMS) as a coupling agent. This led to a novel synthesis that combined the sol-gel process with in situ ring-opening polymerisation of the solvent (tetrahydrofuran), resulting in innovative silica/polytetrahydrofuran/PCL (SiO2/PTHF/PCL) hybrids with unprecedented features. They showed tailorable mechanical properties in a broad range of compositions (2.5-63.4 wt.% inorganic), from polymer-like to glass-like behaviour with excellent flexibility and ability to recover the deformation. Hybrids with SiO2 <40 wt.% maintained their mechanical properties in wet environments; they also unexpectedly showed the intrinsic potential to autonomously self-heal when damaged in dry conditions. 3D grid-like hybrid scaffolds containing ~24 wt.% inorganic were successfully fabricated through 3D extrusion printing from sol-gel process. This technique relies on the gradual increase of viscosity occurring during gelation, which makes the viscous sol a suitable ink for direct extrusion within a limited time window. The obtained scaffolds showed mechanical properties similar to native cartilage and were proven to stimulate the production of collagen Type II, typical of hyaline cartilage, during chondrocyte culture. Therefore, SiO2/PTHF/PCL hybrid scaffolds have great potential for articular cartilage regeneration.Open Acces