A new study of bone formation from stem cells seeded on 3D printed bioactive scaffolds combined with different mineral additives showed that some of the scaffold mineral composites induced bone-forming activity better than others.
The properties and potential to use these bioactive scaffolds in bone regeneration applications are discussed in an article published in Tissue Engineering, Part A, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. The article is available free on the Tissue Engineering website until March 13, 2017.
Ethan Nyberg, Alexandra Rindone, Amir Dorafshar, and Warren Grayson, Johns Hopkins University School of Medicine and Johns Hopkins University, Baltimore, MD, examined the print quality of several different composite 3D-printed bone scaffolds.
In the article entitled “Comparison of 3D-Printed Poly-ε-caprolactone Scaffolds Functionalized with Tricalcium Phosphate, Hydroxyapatite, Bio-Oss, or Decellularized Bone Matrix,” they report on the mechanical and structural properties of the various porous scaffolds, to which they added adipose-derived stem cells. The researchers then assessed the bone-inducing properties of each hybrid scaffold, measuring osteoblast formation, calcium content, and collagen expression.
“In the continuum of materials used to regenerate bone, harnessing the power of both biomaterial scaffolds and known crystalline bone regeneration materials provides maximal flexibility in therapy,” says Tissue Engineering Co-Editor-in-Chief Peter C. Johnson, MD, Principal, MedSurgPI, LLC and President and CEO, Scintellix, LLC, Raleigh, NC.
The researchers successfully 3D printed several composite PCL-mineral scaffolds and compared their relative abilities to drive osteo-induction in ASCs. In this 3D printing system, PCL-BO and PCL-DCB exhibited greater ability for osteo-induction than synthetic materials such as PCL-HA or PCL-TCP. PCL-DCB and PCL-BO blends induced significant increases in mineral deposition and upregulation of collagen and osteonectin relative to PCL only scaffolds.
The PCL-TCP and PCL-HA scaffolds also showed some enhanced osteo-inductivity, though not to the same extent. This greater induction might be due to the presence of a collagen phase (as measured by Raman spectra), the structure of the apatite, or greater presence of the BO and DCB particles on the surface of the struts following the printing process. These results indicate that doping 3D-printed PCL scaffolds with DCB or BO might better support bone healing in vivo in comparison to TCP- or HA-doped grafts.