Impressão 3D de scaffolds de PLDLA-TMC como modelo para engenharia tecidual de cartilagem: da reologia ao biorreator

Abstract

The increase in life expectancy and the practice of physical activities have impacted the number of traumatic injuries and degenerative diseases, such as meniscal tears and osteoarthritis. The meniscus is composed of fibrocartilaginous tissue subjected to significant mechanical stresses, with low intrinsic repair capacity. When injured, it is often partially or completely removed, leading to future joint complications. Despite available commercial devices, finding a solution for total meniscectomy remains a challenge. In order to explore solutions that may mitigate the problems associated with meniscal injuries, a study was conducted to characterize the Poly(L-co-D,L lactic acidco-trimethylene carbonate) (PLDLA-TMC) terpolymer in proportions of 60/40 and 70/30 regarding its physicochemical, thermal, and rheological properties, aiming for the printing of three-dimensional (3D) scaffolds. Rheological tests revealed the pseudoplastic behavior of the materials, which is indispensable for the printing process. From the characterization of the scaffolds, printing temperature was the factor that most influenced material degradation. When subjected to mechanical compression testing, PLDLA-TMC 60/40 scaffolds showed an elastic modulus (2.9 MPa) similar to the human meniscus (1 MPa), making them eligible for application as meniscal prostheses, as opposed to PLDLA-TMC 70/30 scaffolds. Printing speed proved to be less significant in reducing the molecular weight of the scaffolds, while the material residence time in the printer impacted this property. In vitro degradation testing demonstrated the material's stability over the 4-week study period. Citocompatibility and differentiation assays on PLDLATMC 60/40 printed scaffolds, both in static and dynamic culture, demonstrated their potential as cell carriers in cartilage tissue engineering approaches.