Mechanical properties and in vitro bioactivity of Ca5(PO4)2SiO4 bioceramic

J Biomater Appl. 2012 Feb;26(6):637-50. doi: 10.1177/0885328210383599. Epub 2010 Sep 28.


Pure Ca(5)(PO(4))(2)SiO(4) bioceramic was first prepared by a sol-gel method using triethyl phosphate, tetraethoxysilane, and calcium nitrate tetrahydrate as original materials. Simulated body fluid (SBF) immersion tests revealed that Ca(5)(PO(4))(2)SiO(4) samples had a greater in vitro apatite-forming ability than hydroxyapatite (HA). After soaking Ca(5)(PO(4))(2)SiO(4) samples in the SBF for 1 day, bone-like apatite precipitated on the surfaces and the apatite layer became thicker with increasing the soaking time. However, few bone-like apatites precipitated on the HA samples even after soaking in the SBF for 7 days. The good in vitro bioactivity of Ca(5)(PO(4))(2)SiO(4) samples was attributed to the silanol (Si-OH) groups and greater solubility of Ca(5)(PO(4))(2)SiO(4). In addition, hot-pressed Ca(5)(PO(4))(2)SiO(4) ceramic exhibited lower bending strength and elastic modulus than hot-pressed HA, since the former had a lower relative density than the latter. The results have shown that Ca(5)(PO(4))(2)SiO(4) is a potential candidate material for bone repair.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apatites / metabolism*
  • Biocompatible Materials / metabolism*
  • Calcium Phosphates / chemistry
  • Calcium Phosphates / metabolism*
  • Ceramics / chemistry
  • Ceramics / metabolism*
  • Durapatite / metabolism*
  • Elastic Modulus
  • Humans
  • Materials Testing
  • Phase Transition
  • Powder Diffraction
  • Silicates / chemistry
  • Silicates / metabolism*
  • X-Ray Diffraction


  • Apatites
  • Biocompatible Materials
  • Calcium Phosphates
  • Silicates
  • Durapatite
  • calcium phosphate