The ideal bone substitute material should be mechanically strong, biocompatible with a resorption rate matching the rate of new bone formation. Brushite (dicalcium phosphate dihydrate) cement is a promising bone substitute material but with limited resorbability and mechanical properties. To improve the resorbability and mechanical performance of brushite cements, we incorporated gypsum (calcium sulfate dihydrate) and diazonium-treated polyglactin fibers which are well-known for their biocompatibility and bioresorbability. Here we show that by combining brushite and gypsum, we were able to fabricate biocompatible composite cements with high fracture toughness (0.47 MPa·m^1/2) and a resorption rate that matched the rate of new bone formation. Adding functionalized polyglactin fibers to this composite cement further improved the fracture toughness up to 1.00 MPa·m^1/2. XPS and SEM revealed that the improvement in fracture toughness is due to the strong interfacial bonding between the functionalized fibers and the cement matrix.

This study shows that adding gypsum and functionalized polyglactin fibers to brushite cements results in composite biomaterials that combine high fracture toughness, resorbability, and biocompatibility, and have great potential for bone regeneration.

理想的骨替代材料应该具有机械强度、生物相容性以及与新骨形成速率相匹配的再吸收速率。透钙磷石（二水合磷酸二钙）骨水泥是一种很有前途的骨替代材料，但其再吸收性和机械性能有限。为了提高透钙磷石水泥的再吸收性和机械性能，我们加入了以生物相容性和生物再吸收性而闻名的石膏（二水合硫酸钙）和重氮处理的聚乳酸纤维。在这里，我们表明，通过将透钙磷石和石膏相结合，我们能够制造出具有高断裂韧性 (0.47 MPa·m ^1/2) 和与新骨形成率相匹配的再吸收率。向该复合水泥中添加功能化聚乳酸纤维进一步提高了断裂韧性，最高可达 1.00 MPa·m ^1/2。XPS 和 SEM 表明，断裂韧性的提高是由于功能化纤维和水泥基体之间的强界面结合。

这项研究表明，在透钙磷石水泥中加入石膏和功能化聚乳酸纤维，可以得到兼具高断裂韧性、再吸收性和生物相容性的复合生物材料，具有巨大的骨再生潜力。