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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 [...]

For the medical diagnosis, radiopaque materials (RM) made from high specific gravity elements like Pt, Au, Ta, Iodine, Bromine are either attached or blended or coated on an implant to makes it detectable under X-ray/Fluoroscopy/CT-Scan. RM facilitate the surgeon in an operation theatre to position an implant during the surgery. Mainly, RM are non-degradable, thus in case of biodegradable implants, it may detach from the body and accumulate in vital organ cause serious health issue. Therefore, a new bioresorbable radiopaque material (BRM) was produced by alloying the high specific gravity elements Zn (35% w/w) and Y(4% w/w) with Mg metal. In this alloy, three main phases were identified, alpha Mg, Mg 7 Zn 3 and icosahedral quasicrystalline I-phase Mg 3 Zn 6 Y, which reinforce the Mg matrix. Hereafter, BRM was powdered to a size of less than 25 microns and blended in different ratios with bioresorbable poly-L-lactic acid (PLLA) for fabricating PLLA/BRM bio-composite. BRM microparticles were uniformly distributed and interfacial bonded with the matrix. The X-ray was passed through bio-composite to capture µCT radiograph for evaluating linear attenuation co-efficient (µ) and optical density (OD). Thermal analysis reveals that BRM particles act as a nucleating site and enhance the crystallinity of the polymeric chain. During the In Vitro accelerated degradation study, the alkaline nature of BRM neutralise the acidity of PLLA and balance the pH of the body fluid to reduce the inflammatory reactions, but this compromises the stability of the polymer as it increases the decomposition rate. [ABSTRACT FROM AUTHOR]