Porous Poly(ε-caprolactone)–Poly(l‑lactic acid) Semi-Interpenetrating Networks as Superior,
Defect-Specific Scaffolds with Potential for Cranial Bone Defect Repair
The treatment of
irregular cranial bone defects is currently limited
due to the graft resorption that can occur when an ill-fitting interface
exists between an autograft and the surrounding tissue. A tissue engineering
scaffold able to achieve defect-specific geometries could improve
healing. This work reports a macroporous, shape memory polymer (SMP)
scaffold composed of a semi-interpenetrating network (semi-IPN) of
thermoplastic poly(l-lactic acid) (PLLA) within cross-linked
poly(ε-caprolactone) diacrylate (PCL-DA) that is capable of
conformal fit within a defect. The macroporous scaffolds were fabricated
using a fused salt template and were also found to have superior,
highly controlled properties needed for regeneration. Specifically,
the scaffolds displayed interconnected pores, improved rigidity, and
controlled, accelerated degradation. Although slow degradation rates
of scaffolds can limit healing, the unique degradation behavior observed
could prove promising. Thus, the described SMP semi-IPN scaffolds
overcome two of the largest limitations in bone tissue engineering:
defect “fit” and tailored degradation