This work aimed at investigating the possibility and effectiveness of osteoinductive calcium phosphate(CaP)ceramics to close the drilled skull holes and prevent the postoperative cerebrospinal fluid(CSF)leaking in children’s endoscopic neurosurgery.Five children patients(four boys and one girl,3-to 8-years old)underwent the surgery,in which the endoscopic third ventriculostomy(ETV)was operated in four cases of hydrocephalus,and biopsy and ETV were both performed in one case of pineal tumor.The drilled skull holes were filled with the commercial osteoinductive CaP ceramics.The patients were followed up by CT scan at 1,7 days,3 and 6 months postoperatively.All the five cases were successful,and the holes were closed well after filled with the ceramics.The follow-up survey showed that no CSF leaking or rejection reaction was found.The CT scan indicated that the drilled holes began healing at 7 days postoperatively,and a relatively complete healing happened at 6 months postoperatively.The excellent ability of the CaP ceramics to induce bone regeneration was also confirmed by repairing the skull defects in a monkey model.The results of μ-CT and histological analysis showed that a bony structure with irregular array occurred at the defect area,and the newly formed bone volume density reached 65.7%.In conclusion,the osteoinductive CaP ceramics could be an ideal material to treat the drilled skull holes in children’s endoscopic neurosurgery and prevent CSF leaking afterwards.However,further investigation with more cases and longer follow-up was required to evaluate the clinical effect.
The discovery of osteoinductivity of calcium phosphate(Ca-P)ceramics has set an enduring paradigm of conferring biological regenerative activity to materials with carefully designed structural characteristics.The unique phase composition and porous structural features of osteoinductive Ca-P ceramics allow it to interact with signaling molecules and extracellular matrices in the host system,creating a local environment conducive to new bone formation.Mounting evidence now indicate that the osteoinductive activity of Ca-P ceramics is linked to their physicochemical and three-dimensional structural properties.Inspired by this conceptual breakthrough,many laboratories have shown that other materials can be also enticed to join the rank of tissue-inducing biomaterials,and besides the bones,other tissues such as cartilage,nerves and blood vessels were also regenerated with the assistance of biomaterials.Here,we give a brief historical recount about the discovery of the osteoinductivity of Ca-P ceramics,summarize the underlying material factors and biological characteristics,and discuss the mechanism of osteoinduction concerning protein adsorption,and the interaction with different types of cells,and the involvement of the vascular and immune systems.
目的：研究多孔磷酸钙骨组织工程支架的表面微纳米化改性。方法通过双氧水发泡法制备多孔磷酸钙骨组织工程支架,利用水热法对材料进行微纳米化表面改性。通过扫描电镜观察材料的显微结构,通过 X 射线衍射仪分析测试材料改性层相成分。结果材料改性处理后,孔隙率为（63±8）%,大孔孔径为（310±30）μm。材料表面及内孔壁生成羟基磷灰石微纳米晶粒或晶须,晶须长20-40μm,直径为100-300 nm。结论多孔磷酸钙陶瓷材料的内外表面经水热法处理微纳米化表面改性后,材料性能得到提升。
