Bioceramic-based scaffolds with antibacterial function for bone tissue engineering:A review

Bone defects caused by trauma,tumor,congenital abnormality and osteoarthritis,etc.have been substantially impacted the lives and health of human.Artificial bone implants,like bioceramic-based scaffolds,provide significant benefits over biological counterparts and are critical for bone repair and regeneration.However,it is highly probable that bacterial infections occur in the surgical procedures or on bioceramic-based scaffolds.Therefore,it is of great significance to obtain bioceramic-based scaffolds with integrative antibacterial and osteogenic functions for treating bone implant-associated infection and promoting bone repair.To fight against infection problems,bioceramic-based scaffolds with various antibacterial strategies are developed for bone repair and regeneration and also have made great progresses.This review summarizes recent progresses in bioceramic-based scaffolds with antibacterial function,which include drug-induced,ion-mediated,physical-activated and their combined antibacterial strategies according to specific antibacterial mechanism.Finally,the challenges and opportunities of antibacterial bioceramic-based scaffolds are discussed.

Lanthanum doped octacalcium phosphate/polylactic acid scaffold fabricated by 3D printing for bone tissue engineering

Lanthanum(La)has tremendous potential in the treatment and prevention of bone diseases especially osteoporosis and metabolic disorders.However,controlling its distribution and keeping the release of La^(3+)ions sustained and steady in the body is still a big challenge.In this study,we prepared La-OCP powders via co-precipitation method,and further prepared La-OCP/PLA porous scaffolds by 3 D printing.La^(3+)was successfully introduced into the OCP crystal structure and substituted Ca^(2+)at the Ca-5 and Ca-8 sites.In particular,some La^(3+)ions were deposited on the crystal surface in the form of nanoparticles.Both octacalcium phosphate(OCP,Ca_(8)H_(2)(PO_(4))_6·5 H_(2)O)crystals and nanoparticles played as the carriers for La^(3+)ions.The La-OCP/PLA scaffolds displayed obvious mineralization effects and sustained release of La^(3+).The scaffolds contained a uniform structure with rough micro surface topography which acted as a suitable pathway for BMSCs cells to adhere,grow and proliferation.At a certain La^(3+)concentration,the extracts from La-OCP/PLA scaffolds increased the expression of osteogenesis-related genes,thus promoting the osteogenic differentiation of BMSCs.Moreover,the extracts regulated the immune responses.The experiment in vivo proved that La-OCP/PLA porous scaffolds were safe and could enhance bone defect regeneration in vivo.These findings suggest that 3 D printed La-OCP/PLA porous scaffolds have promising potentials in bone tissue engineering.