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Poly(lactic acid) (PLA) is one of the most promising biopolymers extensively used in food, packaging, medical and pharmaceutical industries. It is due to favorable physicochemical properties, in-situ hydrolytic degradation and well-established processing parameters. However, in medical engineering applications, PLA shows some drawbacks like low cell adhesion, biological inertness, slow degradation rate and high acid inflammation. These shortcomings of pure PLA could be addressed by blending it with other bioresorbable materials and compatibilizers. This review provides comprehensive information on different PLA composites in the field of tissue engineering, implants, injury management and drug delivery systems. The PLA-based composites are divided into four parts: PLA/polymer, PLA/metal, PLA/ceramic, and PLA/nanoparticles. It also investigates various synthesis process, role of different compatibilizers, in vitro studies and their in vivo applications. Highlights * Review the trends of bioresorbable PLA blends/composites. * Extensively focused on PLA blend with polymer, metal, ceramic, and nanoparticles. * Role of reinforcement and compatibilizer to overcome shortcomings of PLA implant. * Highlights advantages, limitations, and properties of different types of PLA implants. * Discuss various clinical applications and future of PLA blends/composite scaffolds. KEYWORDS biomaterial, compatibilizer, PLA composite, PLA implants, PLA nanoparticles, 1 | INTRODUCTION A wide range of bioresorbable polymeric materials (BPM) has been investigated for biomedical engineering applications. The major advantage of BPM is to eliminate the need for a [...]

Bioresorbable polymeric stents (BPS) can become a promising alternative over permanent stents, as it reduce in-stent thrombosis, endothelial dysfunction, and thrombogenicity. Although, a few limitations like uncontrolled degradation, inadequate strength, and lack of radiopacity restrict its application. Thus, a novel bioresorbable radiopaque Mg-Zn-Y Alloy (BRM) of high effective atomic number ([Z.sub.eff]) was developed to reinforce and attenuate X-rays in the polymers. After that, the optimized BRM microparticles were blended with radiolucent poly (L-lactide)/poly ([epsilon]-caprolactone) (PLLA/PCL) polymer and extruded into biaxially expanded (BAE) tubes. Further, in this work, BAE tubes of PLLA/PCL/ BRM and PLLA/PCL were cut using the optimized Femtosecond laser machine (FSLM) parameters for fabricating cardiovascular stents. These stent materials were assessed to sustain the angioplasty procedure, such as radial strength, crimping, recoil, expansion process, and performance under cycling loading. Highlights * A novel biodegradable radiopaque Mg-Zn-Y alloy was developed. * Adding Mg alloy (5% wt.) in PLLA/PCL imparts X-ray visibility. * Composite stents show better compressive radial strength and flexibility. * It also reveals low crimping recoil, expansion recoil, and foreshortening. * Composite stents can withstand arterial vasomotion better than PLLA/PCL. KEYWORDS Biopolymer, Bioresorbable polymer, Composite stents, Crimping, Radiopacity, Recoil, 1 | INTRODUCTION Today, metallic stents are preferred due to their high impact strength, wear resistance, ductility, and toughness. (1) It demonstrates a high success rate in Percutaneous Coronary Intervention [...]

All bioresorbable polymeric implants are radiolucent, making them undetectable under the X-rays. Therefore, to improve their X-ray visibility, the high effective atomic number (Zeff) material such as Pt, Au, Ta, Ba, or its alloy are attached to the body of the bioresorbable implant. However, during the in vivo degradation, these bio-inert heavy metals can either detach or leach out from the lesion site and accumulate into the vital organ, leading to severe health complications. Thus, as a strategy, the novel biodegradable and radiopaque Mg alloy was produced to impart X-ray visibility in the biopolymer. Here, the Mg was alloyed with the optimized ratio of heavy metals, i.e., Zn and Y. The radiopaque Mg alloy was characterized and powdered to the size of 25–20 µm. Further, it was blended with radiolucent Poly-L-lactic acid (PLLA) and polycaprolactone (PCL) polymer. The Bi-axially expanded (BAE) tubes of PLLA/PCL and PLLA/PCL/Mg alloy (5% wt.) were extruded for fabricating cardiovascular stents. The BAE tube comparison studies were performed for thermal stability, wettability, surface roughness, and mechanical properties. The potential of 5% Mg alloy in the polymeric matrix was evaluated as a nucleating, reinforcing, and radiopaque agent. In vitro accelerated degradation study was performed in the physiological fluid to evaluate the pH variation and decomposition rate. Finally, in vitro biocompatibility was assessed by evaluating the behavior of L929 fibroblast cells, followed by the blood biocompatibility test on the blends. [ABSTRACT FROM AUTHOR]