Resorbable Layered Double Hydroxides‐Based Composite Implants Synergistically Accelerates Critical‐Sized Defect Closure

The study focuses on the fabrication of a composite implant composed of MgAl layered double hydroxides (LDH), gelatin, and diosgenin and its regeneration potential in experimentally‐induced tibial defect in rabbits. The implant is fabricated by blending and lyophilization technique and eventually cross‐linked using glutaraldehyde. The implant is characterized by attenuated total reflectance (ATR) spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and compressive strength. A sustained release of diosgenin occurs over a period of 28 days. The osteogenic activity is analyzed by alkaline phosphatase activity and alizarin red S staining; that aid in determining the extent of biomineralization. The results also demonstrate that LGD100 implant stimulates the expression of genes associated with osteoblastic activities in MG‐63 cells, namely type I collagen, osteocalcin, and osteopontin. The bone regeneration capacity of diosgenin‐loaded gelatin‐based LDH implant is then tested by creating critical bone defects in the tibia of rabbits by using empty bone defects as controls. Periodic radiographs are taken which show promising results. Histological and immunohistochemical staining confirm that after treatment with LGD100, new bone is formed at the defect site. This study suggests that LGD100 implant aids in faster bone formation as it mimics the natural properties of bone. Alkaline phosphatase, type I collagen, osteocalcin, and osteopontin play a crucial role in osteogenesis. In this work, the fabrication of a homogenous composite implant comprising MgAl LDH, gelatin, and diosgenin and its influence on these biomarkers are reported. The optimized formulation is proved to impart a synergistic effect toward the enhanced healing of an experimentally‐induced critical‐size tibial defect.