Get best of the week

How table salt and proteins will increase implant survival

A fairly large number of our publications are devoted to biomedical technologies. Recently, especially. No, we do not narrow our profile, there are just a lot of good news on the topic. By the way, here's another one - about polymer implants, table salt, minerals, proteins and mice.

31809441957-06e93b31d4-k

One of the most widely used materials for the manufacture of polymer bone implants is polyetheretherketone (PEEK) - it is durable, resistant to aggressive chemical environments, wear-resistant, biocompatible. PEEK is used mainly in spinal surgery - for prosthetics of the intervertebral discs. However, it is also promising as a material for the manufacture of tubular and flat bone implants. In this case, it is required to ensure a strong fusion of PEEK with the patient’s bone. For this, additional processing of the material is necessary to create a porous structure into which bone tissue would grow. However, to date, none of the methods used (for example, foaming with gas or phase separation) has not given sufficient structural similarity with natural bone.

Scientists from NUST "MISiS" and NITsEM them. N.F. The Gamaleis have developed a combinatorial approach to implant creation, which includes the manufacture of a porous implant from PEEK or PEEK with the addition of hydroxylapatite, the main mineral component of bone tissue, as well as two proteins, erythropoietin (EPO) and bone morphogenetic protein BMP-2.

« . , , – , , . . 80%- », – , iPhD «» «» .

To form the structure, salt crystals of two sizes were used - 106-200 micrometers and 40-75 micrometers. The former allowed the formation of pores in the material, the latter - a microrelief on their surface. If pores are needed to a greater extent for the germination of blood vessels and bone tissue, then the microrelief promotes the attachment of osteoblasts to the implant surface - the patient’s own cells that form bone tissue.

« BMP-2, . , , . , », — . .. , , , . .. .

In further experiments, samples of the material were implanted into a 4-mm round skull defect in eight groups of laboratory mice. In each of the groups, the samples had a different composition — pure PEEK, PEEK without proteins, PEEK with different protein concentrations, the same options with the addition of HAP. The ninth group was the control - the implant was not implanted.

As the experiment showed, the optimal combinations are PEEK (with or without hydroxylapatite), EPO 3.5 micrograms and BMP-2, also 3.5 micrograms. It was in these groups that the maximum overgrowing of the bone defect was achieved in 6 weeks of the experiment. In general, due to the introduction of recombinant proteins, it was possible to increase the implant survival rate (which is expressed in an increase in the percentage of bone tissue) by 4-6 times. This will allow the patient to recover faster after surgery; in addition, new bone tissue at the site of the defect will be able to withstand the same mechanical stress as before the operation.

Scientists plan to continue work on improving polymer implant materials, including using bioresorbable, that is, compounds that dissolve over time.

More articles:


All Articles