Strontium delivery on topographical titanium to enhance bioactivity and osseointegration in osteoporotic rats

Abstract

Strontium delivery on topographical titanium to enhance bioactivity and osseointegration in osteoporotic ratsThis work completed by Wen Jin, Li Jinhua et al. indicated that a topographical titanium surface with substituted strontium could promote osteogenic diff erentiation, inhibit osteoclast formation in vitro and have a good osseointegration eff ect in osteoporotic rats. 4790 | J. Mater. Chem. B, 2015, 3, 4790--4804 This journal is Osseointegration remains a major clinical challenge in osteoporotic patients. Strontium (Sr) has been shown to be a significant therapy to favor bone growth by both increasing new bone formation and reducing bone resorption. In this study, we attempt to chemically functionalize Ti implants by micro-arc oxidation, alkali treatment and ion exchange. This functionalized Ti surface possessed a hierarchical topography with Sr incorporation, which can release Sr ions at a slow rate. To our knowledge, this work is the first to use this type of Sr-doped Ti surface to address osteoporotic bone mesenchymal stem cells (BMSCs) in the dual directions of bone regeneration, bone formation and bone resorption. The modified surface was demonstrated to remarkably enhance the adhesion, spreading, and osteogenic differentiation of BMSCs in vitro. The effect of the wash-out solution from various groups on osteoporotic BMSCs was also investigated. The Sr-doped group can improve the ALP activity and osteogenic gene expression.Moreover, the Sr-doped group and the wash-out solution show the most inhibition in osteoclast formation and maturation. Furthermore, the increased bioactivity of the hierarchical structure was also confirmed with the ovariectomized rat femur model in vivo. The outcome of fluorescence labeling, histology and histomorphometric analysis demonstrated a significant promotion of osseointegration in ovariectomized rats. Altogether, the experimental data indicate that the fabrication of a Sr-doped hierarchical Ti surface is a meaningful attempt to incorporate the Sr nutrient element into Ti-based implants, and it is expected to be exploited in developing better osseointegration for osteoporotic patients.

Surface Treatments and Functional Coatings for Biocompatibility Improvement and Bacterial Adhesion Reduction in Dental Implantology

“…More specifically, the incorporation of strontium (Sr) on the surface of titanium implants has been proposed in order to accelerate the osseointegration process. Modification of Ti surfaces to incorporate Sr ions has been achieved by means of chemical treatments using a strontium acetate solution [35] as well as by means of micro arc oxidation [36].…”

“…Interesting attempts have recently been proposed to functionalize titanium implants with strontium. Micro-arc oxidation, alkali treatment and ion exchange were used to incorporate Sr [36] so as to attain a Sr-doped Ti surface. The modified surface remarkably enhanced the adhesion, spreading and osteogenic differentiation of mesenchymal stem cells in vitro, even when compared to a control chemically and topographically identical except for Sr content.…”

TiO2 bioactive implant surfaces doped with specific amount of Sr modulate mineralization

“…Sr has an effect on osteoblast proliferation and osteoclast resorption with consequently stimulation of bone growth and inhibition of bone resorption [31,32]. Thus, Sr is accounted as a potential bioactive element showing promising results in vitro [31][32][33][34] and in vivo [25,33,[35][36][37].…”

Study of Sr–Ca–Si-based scaffolds for bone regeneration in osteoporotic models

“…Excessive Sr may lead to cytotoxicity to human organs or bioactivity, making control of the release rate of Sr vital with regard to bone tissue engineering. 18,19 The current data revealed that sustained release of Sr could be achieved and was much safer than the data that caused adverse cellular effects in the literature. 20 The technology of loading or incorporating bioactive proteins such as growth factors onto tissue-engineered scaffolds acts as a favourable method to enhance the biological properties of biomaterials.…”