Plasma Spray vs. Electrochemical Deposition: Toward a Better Osteogenic Effect of Hydroxyapatite Coatings on 3D-Printed Titanium Scaffolds

Abstract

Surface modification of three-dimensional (3D)-printed titanium (Ti) scaffolds with hydroxyapatite (HA) has been a research hotspot in biomedical engineering. However, unlike HA coatings on a plain surface, 3D-printed Ti scaffolds have inherent porous structures that influence the characteristics of HA coatings and osteointegration. In the present study, HA coatings were successfully fabricated on 3D-printed Ti scaffolds using plasma spray and electrochemical deposition, named plasma sprayed HA (PSHA) and electrochemically deposited HA (EDHA), respectively. Compared to EDHA scaffolds, HA coatings on PSHA scaffolds were smooth and continuous. In vitro cell studies confirmed that PSHA scaffolds have better potential to promote bone mesenchymal stem cell adhesion, proliferation, and osteogenic differentiation than EDHA scaffolds in the early and late stages. Moreover, in vivo studies showed that PSHA scaffolds were endowed with superior bone repair capacity. Although the EDHA technology is simpler and more controllable, its limitation due to the crystalline and HA structures needs to be improved in the future. Thus, we believe that plasma spray is a better choice for fabricating HA coatings on implanted scaffolds, which may become a promising method for treating bone defects.

Galactose Enhances Chondrogenic Differentiation of ATDC5 and Cartilage Matrix Formation by Chondrocytes

“…However, the complex pathogenesis of OA, relevant cellular pathways, and therapeutic approaches have not been fully elucidated. Many methods of modifying the cell phenotype and promoting cartilage matrix regeneration are being investigated, and regulating cellular homeostasis is known to be a critical factor in altering the progression of and treating OA ( Shi et al, 2019 ; Zhang et al, 2019 ; Ito et al, 2021 ; Sun et al, 2021 ).…”

3D-Printed Patient-Customized Artificial Vertebral Body for Spinal Reconstruction after Total En Bloc Spondylectomy of Complex Multi-Level Spinal Tumors

“…Our present study demonstrated that when combined with tumor comprehensive treatment, 3D-printed spinal implant surgery provides patients with excellent long-term spinal function and low risk of local tumor recurrence. Future directions may show further promise with modifications of the surface of the 3D-printed spinal implants to allow for enhanced osteogenic effects and anti-tumor activity[ 28 , 29 ].…”

Bioactive surface modifications through thermally sprayed hydroxyapatite composite coatings: a review of selective reinforcements

“…The technical details and behavior of the plasma spray (PS) process, HVOF, and cold spray (CS) techniques have been com-pared and tabulated in Table 7. Recently, Sun et al 235 compared PS and electrochemical deposition techniques in depositing HA on a 3D printed titanium substrate. The inherent porosity of the 3D printed substrate influenced the coating behavior and osseointegration properties.…”

“…101,179,432,433 Thus, future studies require the scrutinization of the optimum and best additives in the HA matrix and the paramount coating techniques, which can reduce the degradation, enhance the durability and non-infectious nature of the bone implants devoid of negotiation in the biocompatibility of the materials. Recently, Sun et al 235 investigated the surface modifications of 3D printed scaffolds by the plasma spray process, which resulted in a smooth and continuous surface, thus promoting mesenchymal stem cells proliferation in vitro and bone repairability in vivo. A very recent review by Li et al 434 highlighted that 3D and 4D bioprinted implants were facing challenges in the bioactive functionalization of surfaces.…”

“…Many researchers have conducted the in vivo analysis of thermally sprayed, especially plasma-sprayed, HA coatings. 57,59,229,236 Recently, Sun et al 235 showed better plasma-sprayed (PS) HA performance in osteointegration and osteoconduction than the electrodeposited HA on 3D printed titanium. However, this study could not perform quantitative analysis (such as X-ray photoelectron spectroscopy) to support qualitative results (such as micro-CT analysis).…”