Long-term bone response to particulate injectable ceramic

Abstract

Biphasic calcium phosphate particles (BCP), alone or combined with a cellulosic ether vehicle in an injectable composite material (COMP), were implanted in femurs of rabbits. The long-term follow-up (up to 78 weeks) indicated: (1) BCP and COMP induced a foreign-body inflammatory reaction but without fibrous encapsulation. Phagocytosis was mediated by mononucleated macrophages (MC) and giant multinucleated cells (GMNC). Phagocytosis was stronger with COMP and required the recruitment of GMNC while it primarily involved MC in the case of BCP. (2) There appeared to be no significant difference between the bone ingrowth in the defects packed with BCP (dBCP) and in those filled with COMP (dCOMP). Bone reconstruction mostly was achieved after 4 weeks in dBCP but took more time to reach the center of dCOMP. High bone remodeling was observed at the last evaluation times, especially in the case of COMP. (3) Degradation of the materials occurred mainly during the first 4 weeks and was more severe for COMP, which probably was related to the smaller granulometry of its mineral phase. Cell-mediated degradation went on for the 78 weeks and followed two processes: phagocytosis and/or extracellular dissolution of the calcium phosphate particles.

Injectable bone substitute using a hydrophilic polymer

“…All our in vivo and in vitro experiments with this mixture have demonstrated its biocompatibility and biofunctionality [14][15][16]. Further experiments with IBS in rabbit bone in the same conditions using a new HPMC showed that bone ingrowth occurred faster than in experiments with the first HPMC [13] or with macroporous ceramic blocks [17]. The macromolecular parameters influencing bone growth kinetics are currently unknown and require further investigation.…”

“…6). To analyze these behavioral modifications, changes in chemical degradation and macromolecular conformation were studied by infrared spectroscopy [11][12] showed that "the association of cellulosic ether carrier with bioactive ceramic particules does not detrimentally affect the bony incorporation of BCP particles" [13]. All our in vivo and in vitro experiments with this mixture have demonstrated its biocompatibility and biofunctionality [14][15][16].…”

Calcium phosphate-alginate microspheres as enzyme delivery matrices

“…A v ariety of injectable materials, both ceramic-and polymer-based, have been developed for use in multiple orthopaedic applications [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. The combination of ceramic particles with polymeric matrices has also been extensiv ely inv estigated, in an attempt to mimic bone tissue, which may itself be seen as a complex composite material made of organic and inorganic components.…”

“…The combination of ceramic particles with polymeric matrices has also been extensiv ely inv estigated, in an attempt to mimic bone tissue, which may itself be seen as a complex composite material made of organic and inorganic components. Different ceramic phases have been used, hydroxyapatite and tricalcium phosphate being the most common [4][5][6][7][8][9], as well as several polymeric matrices, both from synthetic [10][11][12][13][14] or natural origin, the latter including collagen, chitosan, gelatine and alginate, among others [15][16][17][18][19][20].…”

Combination of poly L-lactic acid nanofiber scaffold with omentum graft for bone healing in experimental defect in tibia of rabbits

“…However, the clinical handling properties of them are limited 45 . Bone cements have been shown to conduct bone growth, but will also induce foreign-body cell reactions 46 . Poor mechanical strength and insufficient adhesion between the bone and the cement as well as low degradation rate restricting the use of some bone filler materials 47,48 .…”