The enhancement of bone regeneration by a combination of osteoconductivity and osteostimulation using β-CaSiO3/β-Ca3(PO4)2 composite bioceramics

Acta Biomater. 2012 Jan;8(1):350-60. doi: 10.1016/j.actbio.2011.08.019. Epub 2011 Aug 28.

Abstract

β-Tricalcium phosphate (β-TCP) is osteoconductive, while β-calcium silicate (β-CS) is bioactive with osteostimulative properties. Porous β-CaSiO(3)/β-Ca(3)(PO(4))(2) composite bioceramic scaffolds with various β-TCP:β-CS ratios were designed to combine both osteoconductivity and osteostimulation in order to enhance bone regeneration. The composite scaffolds were implanted in critical sized femur defects (6×12 mm) for 4, 12 and 26weeks with pure β-TCP and β-CS scaffolds as the controls. The in vivo biodegradation and bone regeneration of the specimens were investigated using sequential histological evaluations, immunohistochemical examination and micro-computed tomography technology. The results showed that the scaffolds with 50 and 80 wt.% β-CS dramatically enhanced the amount of newly formed bone and reduced the degradation rate. In contrast, porous β-CS displayed poor new bone formation due to its rapid degradation, while porous β-TCP showed moderate bone regeneration starting on the surface of the implants, due to a lack of osteostimulation. More importantly, the scaffolds with 50 and 80 wt.% β-CS not only had excellent osteoconductivity, but also stimulated rapid bone formation, and they could degrade progressively at a rate matching the regeneration of new bone. In summary, our findings indicated that the degradation rate and bioactivity of β-CS/β-TCP composite bioceramic scaffolds could be adjusted by controlling the ratio of β-CS to β-TCP, suggesting the potential application of β-CS/β-TCP composite bioceramic scaffolds with 50 and 80 wt.% β-CS component in hard tissue regeneration and bone tissue engineering.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biocompatible Materials / chemistry
  • Bone Regeneration / drug effects*
  • Bone Regeneration / physiology*
  • Bone Substitutes / chemistry
  • Bone Substitutes / pharmacology
  • Bone and Bones / cytology
  • Bone and Bones / drug effects*
  • Bone and Bones / physiology*
  • Calcium Compounds / chemistry
  • Calcium Compounds / pharmacology*
  • Calcium Phosphates / chemistry
  • Calcium Phosphates / pharmacology*
  • Materials Testing
  • Rabbits
  • Silicates / chemistry
  • Silicates / pharmacology*
  • Tissue Engineering / methods
  • Tissue Scaffolds / chemistry
  • X-Ray Microtomography

Substances

  • Biocompatible Materials
  • Bone Substitutes
  • Calcium Compounds
  • Calcium Phosphates
  • Silicates
  • beta-tricalcium phosphate
  • calcium silicate