Probing the structural, mechanical, biomineralization, resorbability and biocompatibility characteristics of ZrO2–CaSiO3 composite dependent on cerium substitutions

Abstract

Composites comprising mechanically stronger ceramic and bioactive alongside resorbable ceramic are a most welcomed choice in load-bearing bone replacement. In this pursuit, the present study aims to investigate the varied levels of cerium additions in the ZrO2–CaSiO3 composite. The influence of cerium concentration on the structural, mechanical, apatite formation, resorbability and in-vitro biological behaviour of the ZrO2–CaSiO3 composite has been undertaken in the current study. Sol-gel synthesis technique has been adopted to yield composite powders and the structural behaviour of the resultant has been performed using various analytical techniques. The results envisaged the crucial role of Ce3+ concentration in accomplishing a phase stable t/c-ZrO2-α-CaSiO3 composite after heat treatment at 1300 °C. XPS analysis revealed the presence of dual oxidation state (+3 and + 4) of cerium in the composite powders and a homogeneous mixture of the composite has been determined from morphological analysis. Mechanical properties determined from nanoindentation indicated better strength displayed by the composite than the natural bone. The immersion tests conducted in simulated body fluids indicated the development of apatite crystals on the composite. Resorbability and biocompatibility tests demonstrated the virtuous appropriateness of the 30 wt% Ce3+/Ce4+ doped t/c-ZrO2-α-CaSiO3 composite for load-bearing bone replacement.