Structure and Properties of Permeable Highly Porous Glass-Ceramics for Orthopedics and Traumatic Surgery

Abstract

Highly porous glass-ceramics based on biogenic hydroxyapatite (50, 60, 66.7, and 70 wt.%) and glass of the SiO2–Na2O–CaO system are prepared using a replication method of the polymer template structure at 900°C. It is established that during sintering of the samples, the biogenic hydroxyapatite decomposes and reacts with the glass phase, which results in the formation of multicomponent glass-ceramics containing buchwaldite NaCaPO4, calcium phosphate silicate Ca5(PO4)2SiO4, calcium pyrophosphate Ca2P2O7, pectolite NaCa2Si3O8(OH), and hydroxyapatite Ca5(PO4)3(OH). The phase ratio in the prepared materials depends on the starting BHA : glass ratio. It is shown that all materials possess permeable open-pore structure with a total open porosity of 78–85%, which increases with content of biogenic hydroxyapatite in the starting composition. The prepared glass ceramics are adsorptive, satisfy structural and mechanical requirements for highly porous implant materials, and can be promising for the replacement of bone tissue defects in orthopedics and traumatic surgery.