A Novel Injectable Calcium Phosphate Cement-Bioactive Glass Composite for Bone Regeneration

Abstract

BackgroundCalcium phosphate cement (CPC) can be molded or injected to form a scaffold in situ, which intimately conforms to complex bone defects. Bioactive glass (BG) is known for its unique ability to bond to living bone and promote bone growth. However, it was not until recently that literature was available regarding CPC-BG applied as an injectable graft. In this paper, we reported a novel injectable CPC-BG composite with improved properties caused by the incorporation of BG into CPC.Materials and MethodsThe novel injectable bioactive cement was evaluated to determine its composition, microstructure, setting time, injectability, compressive strength and behavior in a simulated body fluid (SBF). The in vitro cellular responses of osteoblasts and in vivo tissue responses after the implantation of CPC-BG in femoral condyle defects of rabbits were also investigated.ResultsCPC-BG possessed a retarded setting time and markedly better injectability and mechanical properties than CPC. Moreover, a new Ca-deficient apatite layer was deposited on the composite surface after immersing immersion in SBF for 7 days. CPC-BG samples showed significantly improved degradability and bioactivity compared to CPC in simulated body fluid (SBF). In addition, the degrees of cell attachment, proliferation and differentiation on CPC-BG were higher than those on CPC. Macroscopic evaluation, histological evaluation, and micro-computed tomography (micro-CT) analysis showed that CPC-BG enhanced the efficiency of new bone formation in comparison with CPC.ConclusionsA novel CPC-BG composite has been synthesized with improved properties exhibiting promising prospects for bone regeneration.

A Comprehensive Study of Osteogenic Calcium Phosphate Silicate Cement: Material Characterization and In Vitro/In Vivo Testing

“…[ 10 ] Compressive strengths of hardened bioactive glass (a source of Si)-added CPC was increased compared to Si-free CPC. [ 3,6 ] In addition, Si-added CPC demonstrated improved in vitro and in vivo osteoconduction. [ 6,8 ] Another approach to formulate CPSC is to incorporate monocalcium phosphate (MCP) into calcium silicate cement (CSC).…”

“…[ 3 ] A recent metaanalysis found that the use of bone cement can signifi cantly reduce pain after surgery and prevent further fractures. [ 4 ] The most common and clinically used calcium phosphate cement (CPC) is able to transform into hydroxyapatite (Ca 10 (PO 4 ) 6 (OH) 2 ) under physiological conditions, which forms an apatite layer at the tissue-implant interface and promotes osteogenic differentiation of marrow stromal cells into osteoblast cells. [ 5 ] However, CPC has been reported to insuffi ciently support bone reconstruction at poorly vascularized sites.…”

“…[ 5 ] However, CPC has been reported to insuffi ciently support bone reconstruction at poorly vascularized sites. [ 6 ] To overcome these CPC defi ciencies, several investigators incorporated silicon into CPC to form calcium phosphate silicate cement (CPSC). [ 7,8 ] Silicon can help the proliferation of osteoblast cells and activate cells to produce transforming growth factors.…”

The relevance of biomaterials to the prevention and treatment of osteoporosis

“…Indeed there is increasing research in the field of injectable calcium phosphate cements with recent efforts focusing on incorporating different additives including inorganic bioactive elements, e.g. bioactive glass [55], radiopacifiers, e.g. tantalum oxide or barium sulfate [56], biodegradable polymers to improve the injectability [57]and modifications to incorporate antibiotic releasing capability [58].…”

Stem Cells and Calcium Phosphate Cement Scaffolds for Bone Regeneration

“…Besides hBMSCs and hUCMSCs, stem cells derived from dental tissues, such as dental pulp stem cells (DPSCs) and deciduous teeth stem cells (DTSCs) with the property to form a calcified matrix, also showed promising results for the regeneration of mineralized tissues in combination with CPCs (Xia et al, 2013). hucMsc AnD hbMsc sEEDing On cPc fOr bOnE rEgEnErAtiOn in vivo Strategies for the acceleration of bone regeneration via CPC include the addition of bioactive agents such as osteocalcin, O-phospho-L -serine (Vater et al, 2010), and bioactive glass (Yu et al, 2013). Another strategy for the enhancement of bone regeneration is to combine stem cells with CPC (Zeng et al, 2012;Zou et al, 2012;Chen et al, 2013a).…”