The degradation regulation of 3D printed scaffolds for promotion of osteogenesis and in vivo tracking

Scaffold degradation regulation has become the key aspects in promoting bone regeneration and reconstruction. In the study, a novel stepwise-degraded PLGA/PCL/HA:Yb/Ho/Zn (PPHZ) scaffold was designed to compare with the fast-degradable PLGA/HA:Yb/Ho/Zn (PLHZ) scaffold to investigate the effects of scaffold degradation regulation on osteogenesis and to trace the scaffold degradation process. Micro-CT reconstruction, confocal fluorescence imaging, and histological sections were used for the analyses of the harvested animal samples, which demonstrated that the degradation regulated stepwise-degraded PPHZ scaffold maintaining higher mechanical strength and longer scaffold integrity is more advantageous for in vivo osteogenesis than the fast-degradable PLHZ scaffold. Meanwhile, the multifunctional HZ particles would help the anti-infection and tracking the distribution during scaffold degradation. The PPHZ scaffold may benefit future repair of anti-infective bone defects and in vivo multimodal tracking.