title: Effects of Silicon on Osteoclast Cell Mediated Degradation,In VivoOsteogenesis and Vasculogenesis of Brushite Cement.
abstract: Calcium phosphate cements (CPCs) are being widely used for treating small scale bone defects. Among the various CPCs, brushite (dicalcium phosphate dihydrate, DCPD) cement is widely used due to its superior solubility and ability to form new bone. In the present study, we have studied the physical, mechanical, osteoclast-like-cells differentiation andin vivoosteogenic and vasculogenic properties of silicon (Si) doped brushite cements. Addition of Si did not alter the phase composition of final product and regardless of Si level, all samples included β-tricalcium phosphate (β-TCP) and DCPD. 1.1 wt. % Si addition increased the compressive strength of undoped brushite cement from 4.78±0.21 MPa to 5.53±0.53 MPa, significantly. Cellular activity was studied using receptor activator of nuclear factor κβ ligand (RANKL) supplemented osteoclast-like-cells precursor RAW 264.7 cell. Phenotypic expressions of the cells confirmed successful differentiation of RAW264.7 monocytes to osteoclast-like-cells on undoped and doped brushite cements. An increased activity of osteoclast-like cells was noticed due to Si doping in the brushite cement. An excellent new bone formation was found in all cement compositions, with significant increase in Si doped brushite samples as early as 4 weeks post implantation in rat femoral model. After 4 weeks of implantation, no significant difference was found in blood vessel formation between the undoped and doped cements, however, a significant increase in vasculgenesis was found in 0.8 and 1.1 wt. % Si doped brushite cements after 8 weeks. These results show the influence of Si dopant on physical, mechanical,in vitroosteoclastogenesis andin vivoosteogenic and vasculogenic properties of brushite cements.
authors: W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164, USA.
authors: Sahar
authors: S
authors: Vahabzadeh
authors: W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164, USA.
authors: Mangal
authors: M
authors: Roy
authors: W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164, USA.
authors: Susmita
authors: S
authors: Bose
keywords: Brushite cement; Si doping; TRAP assay; in vitro osteoclastogenesis; in vivo osteogenesis; in vivo vasculogenesis