Calcium phosphate-based anti-infective bone cements: recent trends and future perspectives

Bone infection remains a challenging condition to fully eradicate due to its intricate nature. Traditional treatment strategies, involving long-term and high-dose systemic antibiotic administration, often encounter difficulties in achieving therapeutic drug concentrations locally and may lead to antibiotic resistance. Bone cement, serving as a local drug delivery matrix, has emerged as an effective anti-infective approach validated in clinical settings. Calcium phosphate cements (CPCs) have garnered widespread attention and application in the local management of bone infections due to their injectable properties, biocompatibility, and degradability. The interconnected porous structure of calcium phosphate particles, not only promotes osteoconductivity and osteoinductivity, but also serves as an ideal carrier for antibacterial agents. Various antimicrobial agents, including polymeric compounds, antibiotics, antimicrobial peptides, therapeutic inorganic ions (TIIs) (and their nanoparticles), graphene, and iodine, have been integrated into CPC matrices in numerous studies aimed at treating bone infections in diverse applications such as defect filling, preparation of metal implant surface coatings, and coating of implant surfaces. Additionally, for bone defects and nonunions resulting from chronic bone infections, the utilization of calcium phosphate-calcium sulfate composite multifunctional cement loaded with antibacterial agents serves to efficiently deal with infection, stimulate new bone formation, and attain an optimal degradation rate of the bone cement matrix. This review briefly delves into various antibacterial strategies based on calcium phosphate cement for the prevention and treatment of bone infections, while also discussing the application of calcium phosphate-calcium sulfate composites in the development of multifunctional bone cement against bone infections.