Diffusion of mineral elements evaluated by PIXE at the bone-coral interface

Abstract

Substituting the tissue of human organs with biomaterials is problematic. However, its importance and relevance justify all the efforts made. An interdisciplinary approach is required. We report on our study of a product for bone substitution. Coral is a natural product, the interest of which we have already demonstrated in our previous work. Following sterilization, natural coral was implanted in sheep femurs. We regularly extracted the implants from the femurs to study the kinetics of elemental mineral transformation of the bone substitutes. For the first time ever, and thanks to the PIXE method (particles induced X-ray emission), we were able to measure the concentration of mineral elements at different time intervals after implantation over a whole cross-section. We found a discontinuity of the mineral elements (Ca, P, Sr, Zn, Fe) at the interface between the implant and the receiver. This shows that the osseous attack is not global but, on the contrary, centripetal. Moreover, the fit of the concentration time course indicates that the kinetics of ossification are different for each atomic element and characterize a distinct biological phenomenon. Our analyses confirm the biocompatibility and the ossification of the implanted coral.