Fabrication of nano-structured biphasic calcium phosphate bioceramics to promote bone regeneration

Abstract

In recent years, inorganic non-metallic bone graft materials have attracted growing attention in bone defect repair. Among these, biphasic calcium phosphate (BCP) bioceramics, consisting of hydroxyapatite (Ca 10 (PO 4 ) 6 (OH) 2 , HAp) and β-tricalcium phosphate (Ca 3 (PO4) 2 , β-TCP), have been widely used in bone regeneration and dental therapies due to their biocompatibility, degradability, and osteoconductivity. However, traditional artificial BCP bioceramics have limitations, such as poor osteogenic and angiogenic capacities, which restrict their broader clinical applications To better mimic hierarchical structure of natural bone, a nano-structured BCP bioceramic composed of HAp nano-wires and β-TCP components was fabricated via in-situ hydrothermal treatment using α-TCP/β-TCP ceramic as the precursor. The nano-structured BCP bioceramic was evaluated with in vitro and in vivo experiments Compared to conventional BCP bioceramic, the fabricated nano-structured BCP bioceramic promoted the proliferation, adhesion, and osteogenic and angiogenic differentiation of bone marrow derived mesenchymal stromal cells (BMSCs). Furthermore, it significantly promoted bone defect repair in vivo , as demonstrated in a rat cranial defect model Through composition-structure-function design, nano-structured BCP bioceramics not only resolves the donor crisis associated with autologous bone grafting but also propels bone repair from ‘structural replacement’ to ‘functional regeneration’. Clinical significance: This advancement is reshaping clinical practice standards in orthopedic, oral, and plastic surgery. • Nano-structured biphasic calcium phosphate bioceramics promoted osteogenesis coupled with angiogenesis. • Nano-structured bioceramics improved cell adhension, activated angiogenesis and osteogenesis for enhanced bone regeneration. • These findings provide a strong theoretical basis for the development of nano-structured calcium phosphate bone graft materials.