Investigation of bioresorbable porous implants based on polylactide and polycaprolactone

Abstract

Introduction: One of the urgent problems of thoracic surgery is the development of a bioresorbable porous matrix for intra, or extrapleural implantation in patients with drug-resistant pulmonary tuberculosis. Another important task is the in situ formation of a “biological filling” as an alternative method for correcting the volume of a pleural cavity during the lung surgery. Aims: We studied the local tissue effect of laboratory samples of highly porous matrices with different polylactide/polycaprolactone (PLA/PCL) ratios in rats. Methods and Matherials: The method of subcutaneous implantation in vivo was used. The following samples were in the experiment: № 1 – 3.0%; № 2 – 4.0%; № 3 – 1.7%, while the ratio of polymers in solution was respectively: 3/1; 1/3 and 1/1 PLA/PCL. The method of obtaining highly porous implants was lyophilization. The porosity of the samples ranged from 96.0 to 98.3%. Physical and mechanical tests showed that Young9s modulus varies from 100 to 1800 kPa. In the control group, a sheath of a silicone implant from Mentor was used. The terms of rat’s explantation were 1-2-3-4-5-8-12-14 weeks. Results: When histological examination the more favorable reaction develops using samples № 1, 2 and 3. At the same time, there are signs of resorption of the implant material, its replacement with a fibrous tissue, vascularization and encapsulation, without a perifocal inflammatory process and reactive nature changes. No differences were found between implant modifications. Conclusions: Thus, the in vivo experimental studies show the high biocompatibility of porous matrices based on PLA/PCL as potential materials for the pleural implants development.