In vitro and in vivo evaluation of polylactic acid-based composite with tricalcium phosphate microsphere for enhanced biodegradability and osseointegration

Abstract

A biodegradable polylactic acid composite containing tricalcium phosphate microsphere was fabricated. The composite exhibited enhanced biocompatibility and a well-interconnected porous structure that enabled tissue ingrowth after degradation. The tricalcium phosphate microspheres had an average size of 106 ± 43 μm and were incorporated into the polylactic acid matrix using a high-shear mixer. The resulting bioactivity and hydrophilicity were enhanced to levels comparable to those of a polylactic acid composite containing tricalcium phosphate powder, which is a well-known material used in the medical field. An accelerated 30-day degradation test in HCl revealed successful generation of an open porous structure with ∼98% interconnectivity in the polylactic acid-tricalcium phosphate microsphere composite, demonstrating the potential of this material to induce enhanced osseointegration in the later stage of bone regeneration. The early stage osseointegration was also evaluated by implanting the composite in vivo using a rabbit femoral defect model. After 16 weeks of implantation, the bone-to-implant contact ratio of the polylactic acid-tricalcium phosphate microsphere composite was enhanced owing to tissue ingrowth through the generated pores near the surface.

Model Composites Based on Poly(lactic acid) and Bioactive Glass Fillers for Bone Regeneration

“…In particular their Young’s modulus can be tailored to fit with those of cancellous [ 2 ] or cortical bone [ 3 ]. In addition to improve the mechanical and bioactive properties of the composite, calcium phosphates and bioactive glasses (the main fillers used in orthopedic applications) present the advantage of buffering the acidic degradation of the polyester matrix [ 4 ]. It is important to this phenomenon because a local accumulation of acidic products can induce an inflammatory response from host tissues [ 5 , 6 ].…”

“…The combination of BG and a resorbable polymer makes it possible to meet the mechanical and physiological demands of the host tissue [ 4 ]. The bioactivity and non-cytotoxicity of these composites have been widely demonstrated by in vivo studies [ 9 , 10 , 11 ].…”

Enhanced Osseointegration Ability of Poly(lactic acid) via Tantalum Sputtering-Based Plasma Immersion Ion Implantation

“…1703-06). In vivo experiments with Ta-implanted PLA were conducted using a rabbit femur defect model in male 8 week old New Zealand white rabbits (male, body weight 2.2–2.5 kg, KOSA Bio Inc., Korea) as previously described. ,− Briefly, the rabbits were anesthetized through intramuscular injection with a general anesthetic mixture of xylazine (1.5 mL, Rompun 2%, Bayer Korea, Korea), tiletamine (0.5 mL, Zoletil, Virbac Lab, France), and a local anesthetic, lidocaine (0.5 mL with 1:100000 epinephrine, Yuhan Corporation, Korea). A cylindrical hole (4 mm in diameter and 8 mm in length) was created in each femoral groove parallel to the long axis of the femur using a hand drill.…”

Recent progress in 3D printing degradable polylactic acid‐based bone repair scaffold for the application of cancellous bone defect

“…Different sintering conditions are required for different polymers. The sintering technologies of PLA‐based microsphere scaffolds mainly include high temperature 56,57 /laser sintering 58–60 (using the glass transition temperature [ Tg ] of the material) and solvent sintering (using solvents of different compositions). Yan et al used laser powder bed fusion technology to sinter PLA/nano‐HAP microspheres into microsphere scaffolds with good biocompatibility and osteogenicity 58 .…”