School of Materials Engineering, Jinling Institute of Technology, Nanjing, China.
School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA.
J Biomed Mater Res A. 2021 Dec;109(12):2527-2535. doi: 10.1002/jbm.a.37247. Epub 2021 Jun 29.
This study aimed to investigate the in vivo dissolution of tricalcium silicate (Ca SiO , C S) bone cement in the rabbit femoral defect. Results indicated that C S paste directly integrated with the bone tissue without the protection of the bone-like apatite. Calcium silicate hydrate gel (C-S-H gel) and Ca(OH) were the main components of C S paste. The dissolution model of C S paste was a mass loss rather than a decrease in volume. The initial dissolution of C S paste (0 ~ 6 weeks) was greatly attributed to the release of Ca(OH) , and the later dissolution (>6 weeks) was attributed to the decalcification of C-S-H gel. Although the mass of C S paste could decrease by more than 19 wt % after 6 weeks of implantation, the created pores (<1 μm) were not large enough for the bone tissue to migrate into C S paste. The loss of Ca ions also resulted in the transformation of SiO tetrahedrons from Q and Q to Q , Q , and Q in C-S-H gel. Because only isolated SiO tetrahedrons (Q ) and Ca ions could be absorbed by the bone tissue, C S paste gradually transformed into a silica-rich gel. The fundamental reason for no decrease in volume of C S paste was that the SiO tetrahedron network still maintained the frame structure of C S paste during the implantation.
本研究旨在探讨硅酸三钙（CaSiO3，CS）骨水泥在兔股骨缺损中的体内溶解情况。结果表明，CS 糊剂直接与骨组织结合，而没有骨样磷灰石的保护。硅酸钙水凝胶（C-S-H 凝胶）和 Ca(OH)2 是 CS 糊剂的主要成分。CS 糊剂的溶解模型是质量损失而不是体积减少。CS 糊剂的初始溶解（0~6 周）主要归因于 Ca(OH)2 的释放，而后期溶解（>6 周）归因于 C-S-H 凝胶的脱钙。尽管 CS 糊剂在植入 6 周后质量损失超过 19wt%，但形成的孔（<1μm）不足以使骨组织迁移到 CS 糊剂中。Ca 离子的流失也导致 C-S-H 凝胶中 SiO 四面体从 Q4 和 Q3 转化为 Q2、Q1 和 Q0。由于只有孤立的 SiO 四面体（Q0 和 Q1）和 Ca 离子可以被骨组织吸收，CS 糊剂逐渐转化为富含硅的凝胶。CS 糊剂体积没有减少的根本原因是 SiO 四面体网络在植入过程中仍保持 CS 糊剂的框架结构。
