An Effective Osteogenesis Cryogel & gamma;-PGA/HEMA/PEG Served as Rabbit Orbital Bone Defects Scaffolds

Objective Orbital bone fracture has become very common in recent years, and its related treatments and therapies aim at repairing the defects. Mineralized poly (& gamma;-glutamic acid)/2-hydroxyethyl methacrylate/poly(ethylene glycol) (& gamma;-PGA/HEMA/ PEG) polymeric cryogel is a new type of scaffolding material with an interconnective porous structure. The study aimed to examine its efficacy in the repair of orbital bone defects. Methods The & gamma;-PGA/HEMA/PEG polymeric cryogel was prepared by the cryogelation technique. Orbital bone defects were prepared on twenty-four New Zealand white rabbit. Three groups were made depending on the implanted materials: (1) blank control group; (2) polymeric cryogel group (Gel group); (3) mineralized polymeric cryogel group (M-gel group). Specimens were taken 8 weeks and 16 weeks after implantation for gross observation, micro-computed tomography (& mu;-CT) and hard tissue grinding slices and tissue sections were used to observe the osteogenesis outcome. Results Radiographic results showed that the mineralized cryogel could effectively facilitate the repair of the orbital bone defect completely, with the defective area completely replaced by bone tissue. Histological results proved that the mineralized polymeric cryogel scaffolds could increase the expression of runt-related transcription factor 2 (Runx-2), alkaline phosphatase (ALP), osteopontin (OPN), and platelet endothelial cell adhesion molecule-1 (CD31), which indicated the strengthened angiogenesis and osteogenic capability after the mineralized cryogel transplantation. Conclusion The mineralized polymeric cryogel served as a potential engineering scaffold in the repair of orbital bone defects via angiogenesis and osteogenesis.