Microstructural disassembly of calcium phosphates

Haibo Wang, Jong Kook Lee, Amr M. Moursi, David Anderson, Phillip Winnard, Heather Powell, John Lannutti

Research output: Contribution to journalArticlepeer-review


Microstructural factors may play a role in the osseointegration of calcium phosphates. In this paper, direct microstructural interactions between crystalline calcium phosphates and the biological milieu are reported. Degradation via exposure to osteoblast culture closely resembles in vivo interactions with subcutaneous tissues in a bovine model at early time periods. That these interactions were common to both experiments constitutes one of the few known examples of in vitro-in vivo correspondence. Interestingly, the degradation of phase pure hydroxyapatite (HA) in vitro was more rapid than that of biphasic HA in vivo. In both cases, grain extraction/pullout was frequently observed. This suggests a connection to smaller-scale observations of epitaxial CHA nucleation and growth on pre-existing HA grains. A microstructure in which the grain boundary is dissolving/corroding can apparently be disassembled by forces transmitted through biological structures. These observations are distinct from those of simple non-biological solutions and prove that biological environments can interact with the material beneath the ceramic-cell/ceramic-tissue interface. Many often ignored microstructural factors-grain size, shape, grain boundary strength and the presence of impurity phases-may in fact control degradation. We also suggest that even relatively modest initial grain sizes will, in combination with the mild/absent foreign body response to calcium phosphates, result in lengthy in vivo particle resistence.

Original languageEnglish (US)
Pages (from-to)61-70
Number of pages10
JournalJournal of Biomedical Materials Research - Part A
Issue number1
StatePublished - Jan 1 2004


  • Bioceramic
  • Ceramic
  • Corrosion
  • Intergranular
  • Oxide
  • Transgranular

ASJC Scopus subject areas

  • Ceramics and Composites
  • Biomaterials
  • Biomedical Engineering
  • Metals and Alloys


Dive into the research topics of 'Microstructural disassembly of calcium phosphates'. Together they form a unique fingerprint.

Cite this