A Dexamethasone-Eluting Porous Scaffold for Bone Regeneration Fabricated by Selective Laser Sintering

Abstract

Additive manufacture (AM) has been widely and rapidly applied in fabrication of 3D porous scaffolds for tissue engineering applications. For synthetic polymers of high melting temperature, the melting-extruding technique is the most applied AM method for such fabrication of polymer porous scaffolds. This results in a big challenge to directly process the scaffolds using the polymers and thermosensitive substances simultaneously because of deactivation under high temperature. In this article, the selective laser sintering (SLS) method was proposed to make a poly(L-lactic acid) (PLLA) porous scaffold containing dexamethasone (Dex) simultaneously. Dex was encapsulated in two groups of PLLA−bioactive glass (BG) composite microspheres with an average diameter of 115−120 μm and loading amounts of 0.68 ± 0.09 and 0.84 ± 0.10 μg/mg, respectively. The drug-loading composite microspheres were then fabricated into scaffolds under a laser fluence of 0.83−2.08 J/mm 2 . The average pore size and compressive modulus for the porous scaffold were 450−500 μm and 18−25 MPa, respectively. Drug release experiments showed that Dex was released from the scaffold in a controlled manner until about a month. The eluting time of HPLC tests before or after SLS processing both presented at 4 min indicated no chemical structure changes for the drug. Ex vivo cell experiments also testified the comparable effect of released Dex with commercial products, showing that the bioactivities were not affected after SLS. Implantation of the composite scaffolds in rat cranium defects demonstrated that new bone and blood vessel formation was faster in the Dex-releasing scaffolds than in the groups without drug loading.

Silk fibroin nanoparticles and β–tricalcium phosphate loaded tissue engineered gelatin bone scaffolds: A Nature-based, low-cost solution

“…In various studies, it was reported that the scaffolds produced using different methods for bone regeneration have a porous structure. [51][52][53] The pores in all scaffolds are arranged as interconnected pores, indicating that the pores in the scaffolds provide sufficient space for cell adhesion and proliferation. In Figure 8(d), it is seen that nanoparticle formulations were prepared successfully and they show a monodisperse distribution.…”

Laser Sintering Approaches for Bone Tissue Engineering

“…Promising new advancements such as EBM [205] for metal printing to the use of bioactive coatings [204], antimicrobials, and even drug delivery methods for PBF [206][207][208][209][210][211], will ensure that novel implants can be provided to patients in a timely manner, with the appropriate legislation and oversight from government and regulators. In creating these personalized implants, humans will be equipped with the necessary tools to mitigate the impact of bone-related illnesses and the overall disease burden.…”

Dexamethasone release pattern via a three-dimensional system for effective bone regeneration

“…Microspheres have been used for several studies involving DEX. Sun et al carried out another comparable study in which they combined PLLA with bioglass 3D printed via selective laser sintering [55], offering several advantages over traditional fabrication methods [56,57]. The significant disadvantage of this method is that the higher temperatures necessary to construct the scaffolds may compromise the bioactivity of certain chemicals utilized in BTE [58].…”