Experimental Study of the Corrosive and Biocompatible Properties of Bioresorbable Mg-Ca-Zn Alloy Implants

Abstract

Introduction. Magnesium and its alloys are used as biodegradable bone implants due to their high biocompatibility, however, the problem of use is rapid biodegradation with loss of strength.The purpose of the study. Experimental evaluation of bioresorbable Mg-Ca-Zn alloy implants in vitro and in bone tissue in vivo, in order to determine the optimal rate of biodegradation, biocompatibility and reparative response of bone tissue.Materials and methods. Samples from the obtained Mg-Ca-Zn alloy were coated in a microarc oxidation bath (MDO), and to further determine the optimal phase composition and surface properties, the samples were kept in an electrolyte. The biodegradation of implants was assessed by the loss of mass of samples in vitro, and the release of gas into bone tissue in vivo, and the biocompatibility and reparative response of bone tissue density.Results. All Mg-Ca-Zn coated samples show reduced weight loss compared to the uncoated sample. Magnesium samples with a 20-minute exposure in electrolyte, in the context of its application in anatomically unloaded areas, showed the optimal rate of biodegradation, biocompatibility and reparative response of bone tissue.Discussion. In our study using the microarc oxidation for control the corrosion resistance samples of magnesium alloy shows good biocompatibility and low corrosion rate. We found 5-fold increase in corrosion resistance in coated implants, compared with uncoated samples.Сonclusion. The results of an experimental evaluation of bioresorbable Mg-Ca-Zn alloy implants in vitro and in bone tissue in vivo showed that Mg-Ca-Zn coated samples demonstrate low weight loss during biodegradation, with minimal gas release into the bone.