Analysis of the roles of microporosity and BMP-2 on multiple measures of bone regeneration and healing in calcium phosphate scaffolds

Effect of grain size and microporosity on the in vivo behaviour of β-tricalcium phosphate scaffolds

“…Intensive efforts have been made to determine the most adequate composition and architecture. On the chemical side, many materials varying in composition and architecture have been proposed, including polymers (Ishaug-Riley et al, 1997;Ignatius et al, 2001;Mondrinos et al, 2006;Gogolewski et al, 2008), metals (Ayers et al, 1999;Bobyn et al, 1999;Itala et al, 2001;Witte et al, 2007) and ceramics (Klawitter and Hulbert, 1971;Klein et al, 1985;van Blitterswijk et al, 1986;Eggli et al, 1988;Daculsi and Passuti, 1990;Schliephake et al, 1991;Basle et al, 1993;Metsger et al, 1993;Lu et al, 1999;Flautre et al, 2001;Walsh et al, 2003;Jones and Hench, 2004;Linhart et al, 2004;Hench, 2006;Von Doernberg et al, 2006;Lan Levengood et al, 2010;Murakami et al, 2010;Yuan et al, 2010;Polak et al, 2011;Haugen et al, 2013). These materials present very different resorption rates, and many resorption mechanisms, such as dissolution, hydrolysis (e.g., poly(α-hydroxy acids) (Ignatius et al, 2001)), cell-mediated resorption (Basle et al, 1993;Lu et al, 1999;Von Doernberg et al, 2006;Yuan et al, 2010), corrosion (Witte et al, 2007), enzymatic degradation (Hutmacher, 2000;Vert, 2007), and transport <...>…”

Incorporation of RANKL promotes osteoclast formation and osteoclast activity on β-TCP ceramics

“…The coating efficacy achieved with RANKL adsorption was only 3.5% indicating that RANKL has an insufficient binding affinity to calcium phosphate ceramics. This is in contrast to other bioactive proteins including BMP-2 and VEGF that have been immobilized onto CaP ceramics with superficial adsorption successfully and may be due to the differences in isoelectric points, hydrophobic properties, and structure of the proteins [32,[39][40][41][42]63]. Co-precipitation improved the coating efficacy of RANKL significantly to approximately 90%.…”

“…In the past, research on the reconstruction of bone defects with biomaterials has focused on the stimulation of bone formation with osteoinductive growth factors such as bone morphogenetic proteins 2 and 7 (BMP-2, BMP-7) [37][38][39][40][41][42][43]. Efforts to improve the degradation of ceramic materials have mostly been limited to adjustments of the chemico-physical properties in order to enhance the solubility of the materials such as variations of the Ca/P ratios or the addition of strontium and magnesium [44][45][46][47][48].…”

Fabrication and characterization of 3D complex hydroxyapatite scaffolds with hierarchical porosity of different features for optimal bioactive performance

“…It was also found that both macro and micro porosity could influence osteoinductive activity to certain extent [10,11]. Particularly, the microporosity in the scaffolds is able to make substantial contribution to bone regeneration [15,16]. Adequate microporosity in scaffolds is also necessary to allow in-growth of capillaries to promote osteogenesis [15].…”