Bone-Bonding Strength of a New Composite Bone Cement

Abstract

A composite bone cement designated G2B1 that contains β tricalcium phosphate particles was developed as a bone substitute for percutaneous transpedicular vertebroplasty. In this study, both G2B1 and commercial PMMA bone cement (CMW1) were implanted into proximal tibiae of rabbits with a metal frame fixed on it, and their bone-bonding strengths were evaluated at 4, 8, 12 and 16 weeks after implantation using a detaching test. Some of the specimens were evaluated histologically using Giemsa surface staining and scanning electron microscopy (SEM). It was found that the bone-bonding strength of G2B1 was significantly higher than that of CMW1 at each time point, and significantly increased from 4 weeks to 8 and 12 weeks, while it decreased significantly from 12 weeks to 16 weeks. Giemsa surface staining and SEM showed that G2B1 contacted bone directly without intervening soft tissue in the specimens at each time point, while there was always a soft tissue layer between CMW1 and bone. The results indicate that G2B1 has excellent bioactivity.