Bulk physicochemical, interconnectivity, and mechanical properties of calcium phosphate cements-fibrin glue composites for bone substitute applications.

Calcium phosphate cements (CPCs) and fibrin glue (FG) are used for surgical applications. Their combination is promising to create bone substitutes able to promote cell attachment and bone remodeling. This study proposes a novel approach to create CPC-FG composites by simultaneous CPC setting and FG fibrinogenesis. CPC-FG composites were obtained by mixing CPC powders, i.e. α-tricalcium phosphate, dicalcium phosphate anhydrous and precipitated hydroxyapatite, with FG powder components, i.e. fibrinogen and thrombin, and a 2% Na(2) HPO(4) solution. To study the effect of FG quantity and fibrinogenesis kinetics, long and fast setting FGs were evaluated in amounts of 0.125, 0.250, and 0.500 mL on CPC-FG composites. Physicochemical, interconnectivity, and mechanical properties were measured. Scanning electron microscopy, Micro-computed tomography (μ-CT), X-ray diffraction, and Fourier transform Infrared spectroscopy (FTIR) analyzed morphology, structure, crystallographic, and chemical composition, respectively. FG fibrinogenesis was performed within the CPC. FTIR confirmed this and its interfacial bonding with CPC. μ-CT confirmed a good FG distribution. FG addition affected the CPC when compared with pristine CPC. Adding FG to CPC changed their morphology, density, porosity, setting, cohesion, injectability, interconnectivity, crystallographic and chemical composition and mechanical properties. Moreover, 0.500 mL of long setting FG modified the observed fracture behavior of the CPC-FG.