Degradation and osteogenic potential of a novel poly(lactic acid)/nano-sized β-tricalcium phosphate scaffold

Abstract

Abstract:The purpose of this study was to investigate the influence of nano-sized β-tricalcium phosphate (β-TCP) on the biological performance of poly (lactic acid) (PLA) composite scaffolds by using in vitro degradation and an in vivo model of heterotopic bone formation. Nano-sized β-TCP (nβ-TCP) was prepared with a wet grinding method from micro-sized β-TCP (mβ-TCP), and composite scaffolds containing 0, 10, 30, or 50 wt% nβ-TCP or 30 wt% mβ-TCP were generated using a freeze-drying method. Degradation was assessed by monitoring changes in microstructure, pH, weight, and compressive strength over a 26-week period of hydrolysis. Composite scaffolds were processed into blocks, and implanted into muscular pockets of rabbits after loading with recombinant human bone morphogenetic protein-2 (rhBMP-2). New bone formation was evaluated based on histological and immunohistochemical analysis 2, 4, and 8 weeks after implantation. The in vitro results indicated that the buffering effect of nβ-TCP was stronger than mβ-TCP, which was positively correlated with the content of nβ-TCP. The in vivo findings demonstrated that nβ-TCP enhanced the osteoconductivity of the scaffolds. Although composite scaffolds containing 30% nβ-TCP exhibited similar osteoconductivity to 50% nβ-TCP, they had better mechanical properties than the 50% nβ-TCP scaffolds. This study supports the potential application of a composite scaffold containing 30% nβ-TCP as a promising scaffold for bone regeneration.

Regenerative nanomedicine: current perspectives and future directions

“…Increased osteoconductivity and improved mechanical properties are documented for n beta TCP-coated poly(lactic acid) (PLL) scaffold, which depends on the n beta TCP ratio. 20 Several groups have observed that the incorporation of nano-HA into the gelatin increases the mineralization of the matrix and the alkaline phosphatase activity; this results in active bone growth in rat calvaria. 21,22 Also, the antimicrobial agents mixed with the nanoparticulate components for bone regeneration are thought to be more useful than traditional treatment, especially in cases of long-standing osteomyelitis.…”

Fabrication and characterization of electrospun polylactide/β-tricalcium phosphate hybrid meshes for potential applications in hard tissue repair

“…Both dense and porous composites based on β-TCP have been demonstrated to show excellent performance in the physiological environment and possess several advantages over other calcium phosphates especially with regard to bioresorption [31][32][33][34][35][36]. In contrast only a few papers have been published on the fabrication of electrospun biodegradable hybrid fiber meshes containing β-TCP as inorganic component.…”

Bioabsorbable self-retaining PLA/nano-sized β-TCP cervical spine interbody fusion cage in goat models: an in vivo study

“…Previous studies have indicated that the incorporation of β-TCP into PLA materials can both enhance osteoconductivity and buffer acid products to reduce the inflammation around the implants. 9 Additionally, nano-sized β-TCP exhibits improved mechanical properties and tunable degradability compared with micro-sized powders. Therefore, it is a potentially promising approach to design composite fusion devices that combine the advantages of the two biodegradable materials and overcome the disadvantages of PLA.…”