Fabrication of Novel Biodegradableα-Tricalcium Phosphate Cement Set by Chelating Capability of Inositol Phosphate and Its Biocompatibility

Abstract

Biodegradableα-tricalcium phosphate (α-TCP) cement based on the chelate-setting mechanism of inositol phosphate (IP6) was developed. This paper examined the effect of the milling time ofα-TCP powder on the material properties of the cement. In addition, biocompatibility of the result cementin vitrousing osteoblasts andin vivousing rabbit models will be studied as well. Theα-TCP powders were ballmilled using ZrO2beads in pure water for various durations up to 270 minutes, with a single-phaseα-TCP obtained at ballmilling for 120 minutes. The resulting cement was mostly composed ofα-TCP phase, and the compressive strength of the cement was8.5±1.1 MPa, which suggested that the cements set with keeping the crystallite phase of starting cement powder. The cell-culture test indicated that the resulting cements were biocompatible materials.In vivostudies showed that the newly formed bones increased with milling time at a slight distance from the cement specimens and grew mature at 24 weeks, and the surface of the cement was resorbed by tartrate-resistant acid phosphatase-(TRAP-)positive osteoclast-like cells until 24 weeks of implantation. The presentα-TCP cement is promising for application as a novel paste-like artificial bone with biodegradability and osteoconductivity.