Abstract Osteoarthritis is a degenerative joint disease that limits mobility of the affected joint due to the degradation of articular cartilage and subchondral bone. The limited regenerative capacity of cartilage presents significant challenges when attempting to repair or reverse the effects of cartilage degradation. Tissue engineered medical products are a promising alternative to treat osteochondral degeneration due to their potential to integrate into the patient's existing tissue. The goal of this study was to create a scaffold that would induce site‐specific osteogenic and chondrogenic differentiation of human adipose‐derived stem cells (hASC) to generate a full osteochondral implant. Scaffolds were fabricated using 3D‐bioplotting of biodegradable polycraprolactone (PCL) with either β‐tricalcium phosphate (TCP) or decellularized bovine cartilage extracellular matrix (dECM) to drive site‐specific hASC osteogenesis and chondrogenesis, respectively. PCL‐dECM scaffolds demonstrated elevated matrix deposition and organization in scaffolds seeded with hASC as well as a reduction in collagen I gene expression. 3D‐bioplotted PCL scaffolds with 20% TCP demonstrated elevated calcium deposition, endogenous alkaline phosphatase activity, and osteopontin gene expression. Osteochondral scaffolds comprised of hASC‐seeded 3D‐bioplotted PCL‐TCP, electrospun PCL, and 3D‐bioplotted PCL‐dECM phases were evaluated and demonstrated site‐specific osteochondral tissue characteristics. This technique holds great promise as cartilage morbidity is minimized since autologous cartilage harvest is not required, tissue rejection is minimized via use of an abundant and accessible source of autologous stem cells, and biofabrication techniques allow for a precise, customizable methodology to rapidly produce the scaffold. 
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                            Physical characterization and in vitro evaluation of 3D printed hydroxyapatite, tricalcium phosphate, zirconia, alumina, and SiAlON structures made by lithographic ceramic manufacturing
                        
                    
    
            In this study, lithographic ceramic manufacturing was used to create solid chips out of hydroxyapatite, tricalcium phosphate, zirconia, alumina, and SiAlON ceramic. X-ray powder diffraction of each material confirmed that the chips were crystalline, with little amorphous character that could result from remaining polymeric binder, and were composed entirely out of the ceramic feedstock. Surface morphologies and roughnesses were characterized using atomic force microscopy. Human bone marrow stem cells cultured with osteogenic supplements on each material type expressed alkaline phosphatase levels, an early marker of osteogenic differentiation, on par with cells cultured on a glass control. However, cells cultured on the tricalcium phosphate-containing material expressed lower levels of ALP suggesting that osteoinduction was impaired on this material. Further analyses should be conducted with these materials to identify underlying issues of the combination of material and analysis method. 
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                            - Award ID(s):
- 1762202
- PAR ID:
- 10155723
- Date Published:
- Journal Name:
- MRS Advances
- ISSN:
- 2059-8521
- Page Range / eLocation ID:
- 1 to 10
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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