Evaluation of Bonding Stress for the Newly Suggested Bone Cement: Comparison with Currently Used PMMA through Animal Studies

Abstract

PMMA remains the most popular material of bone cement for orthopaedic surgeries. However, conventional PMMA bone cement still has some problems. For this, we suggested new composite material (BBC) consisting of hydroxyapatite (45%), chitosan (10%) and PMMA. The purpose of this study was to evaluate the bonding stress at the interface of PMMA with additives and host bone using a rabbit model. After 6, 12 weeks of operation, the bonding stresses were evaluated by measuring shear stress through push-out test. The results of the tests showed that after 6 weeks the shear stress of the BBC was 2.65±0.29MPa and the PMMA was 1.21±0.31MPa (p<0.05). However, after 12 weeks, there were no significant differences between BBC and conventional PMMA bone cement. In SEM analysis, bone surface of BBC showed higher roughness than that of conventional PMMA bone cement after push-out test. From the study we conducted, addition of HA particles and chitosan to conventional PMMA bone cement showed promising results. The BBC has clinical potential of bone substitutes replacing conventional PMMA.