Nano-magnesium phosphate hydrogels: efficiency of an injectable and biodegradable gel formulation towards bone regeneration

The use of autografts is considered as gold standard for the treatment of bone tissue defects caused by tumor, disease or trauma. The second surgery for autologous bone harvesting is often linked to donor site morbidity, pain, blood loss and infections (1). To circumvent these issues, synthetic bone grafts made of either organic biopolymers such as poly lactic-co-glycolic acid (PLGA) or collagen (2) and inorganic replacement materials like calcium orthophosphate (CaP) bioceramics are commercially available and frequently used in the clinic (3). The variety of such materials in terms of composition and application form (e.g., pastes, blocks, granules) is huge but most of them do not fulfill all main criteria for adequate bone substitutes: osteogenesis, osteoinductivity, osteoconductivity and osseointegration. Only autologous bone seems to comply with those demands (4).