Hydroxyapatite Microspheres as an Additive to Enhance Radiopacity, Biocompatibility, and Osteoconductivity of Poly(methyl methacrylate) Bone Cement

In-Gu Kang; Cheon-Il Park; Hyun Lee; Hyoun-Ee Kim; Sung-Mi Lee

doi:10.3390/ma11020258

Hydroxyapatite Microspheres as an Additive to Enhance Radiopacity, Biocompatibility, and Osteoconductivity of Poly(methyl methacrylate) Bone Cement

Materials (Basel). 2018 Feb 7;11(2):258. doi: 10.3390/ma11020258.

Authors

In-Gu Kang¹, Cheon-Il Park², Hyun Lee³, Hyoun-Ee Kim^{4

5}, Sung-Mi Lee^{6

7}

Affiliations

¹ Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea. haeronggu@snu.ac.kr.
² Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea. iuy64@snu.ac.kr.
³ Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea. akusaya@snu.ac.kr.
⁴ Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea. kimhe@snu.ac.kr.
⁵ Biomedical Implant Convergence Research Center, Advanced Institutes of Convergence Technology, Suwon-si 16229, Korea. kimhe@snu.ac.kr.
⁶ Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea. msbb419@snu.ac.kr.
⁷ Biomedical Implant Convergence Research Center, Advanced Institutes of Convergence Technology, Suwon-si 16229, Korea. msbb419@snu.ac.kr.

Abstract

This study demonstrates the utility of hydroxyapatite (HA) microspheres as an additive to enhance the radiopaque properties, biocompatibility, and osteoconductivity of poly(methyl methacrylate) (PMMA)-based bone cements. HA microspheres were synthesized using spray drying. They had well-defined spherical shapes, thus allowing for the production of PMMA/HA composites with a very high HA content (20 vol % and 40 vol %). The uniform distribution of these HA microspheres in the PMMA matrix resulted in a remarkable increase in compressive modulus (p < 0.05), while preserving a reasonably high compressive strength. The PMMA/HA bone cements showed much higher radiopacity than PMMA containing BaSO₄ as the additive. This was attributed to the high HA content up to 40 vol %. In addition, the biocompatibility and osteoconductivity of PMMA/HA bone cements were significantly enhanced compared to those of PMMA bone cements containing BaSO₄, which were assessed using in vitro tests and in vivo animal experiments.

Keywords: bone cements; hydroxyapatite; osteoconductivity; poly(methyl methacrylate); radiopaque properties.