Development of glass–ceramic scaffolds for bone tissue engineering: Characterisation, proliferation of human osteoblasts and nodule formation

Bioactive glass and glass-ceramic scaffolds for bone tissue engineering

“…In addition to providing excellent in vitro bioactivity [14,43,94,109,110,115], cell biology behavior [15,105,114,118,119] and favorable mechanical properties [99,102,105], bioactive glassceramic scaffolds have shown superior in vivo behavior (e.g., bone formation, mineralization, higher interfacial strength between implant and bone) compared to the glass in particulate form [113] or compared to other bioactive materials (HA, tricalcium phosphate) [52].…”

“…Recent developments related to bone TE try to bridge this gap and overcome this problem by architectures and components carefully designed from comprehensive levels, i.e., from the macro-, meso-, micrometer down to the nanometer scale [101], including both multifunctional bioactive glass composite structures (see §3.2) and advanced bioactive glass-ceramic scaffolds exhibiting oriented microstructures, controlled porosity and directional mechanical properties [99,[102][103][104][105], as discussed in the following paragraphs. Most studies have investigated mainly the mechanical properties, in vitro and cell biological behavior of glass-ceramic scaffolds [13][14][15]30,43,52,94,95,97,99,, as summarized in Table 1, and scaffolds with compressive strength [99,102] and elastic modulus values [99,105] in magnitudes far above that of cancellous bone and close to the lower limit of cortical bone have been realized. Fu et al [99] fabricated bioactive glass (13-93) scaffolds with oriented (i.e., columnar and lamellar) microstructures and found that at an equivalent porosity of 55-60%, the columnar scaffolds had a compressive strength of 25 ± 3 MPa, compressive modulus of 1.2 GPa, and pore width of 90-110 µm, compared to values of 10 ± 2 MPa, 0.4 GPa, and 20-30 μm, respectively, for the lamellar scaffolds.…”

“…The high amounts of Na 2 O and CaO, as well as the relatively high CaO/P 2 O 5 ratio make the glass surface highly reactive in physiological environments [11]. Other bioactive glass compositions developed over the years contain no sodium or have additional elements incorporated in the silicate network such as fluorine [13], magnesium [14,15], strontium [16][17][18], iron [19], silver [20][21][22][23], boron [24][25][26][27], potassium [28] or zinc [29,30]. Fabrication techniques for bioactive glasses include both traditional melting methods and sol-gel techniques [1, 3,4,10,[31][32][33], the latter are being highlighted elsewhere [34] and are not covered in this review.…”

Synthesis and characterization of hypoxia-mimicking bioactive glasses for skeletal regeneration

“…These two ions have previously been used in TE for a number of different purposes, including as dopants in the production of hydroxycarbonated apatite ceramics 32 , incorporation into polymeric microspheres 33 and also doping in bioactive glasses 22,24,[34][35] . Magnesium can increase chondrocyte proliferation and redifferentiation [36][37] and zinc is involved in bone metabolism 38 .…”

“…Magnesium can increase chondrocyte proliferation and redifferentiation [36][37] and zinc is involved in bone metabolism 38 . Moreover, both magnesium and zinc can improve osteoblast adhesion to scaffolds [39][40] and promote osteogenic differentiation 35,38,[41][42] . 43 .…”