In vitro -Osteoclastic Activity Studies on Surfaces of 3D Printed Calcium Phosphate Scaffolds

Abstract

Various biomaterials have been developed for the use as bone substitutes for bone defects. To optimize their integration and functionality, they should be adapted to the individual defect. Rapid prototyping is a manufacturing method to tailor materials to the 3D geometry of the defect. Especially 3D printing allows the manufacture of implants, the shape of which can be designed to fit the bone defect using anatomical information obtained from the patient. 3D printing of calcium phosphates, which are well established as bone substitutes, involves a sintering step after gluing the granules together by a binder liquid. In this study, we analyzed if and how these 3D printed calcium phosphate surfaces can be resorbed by osteoclast-like cells. On 3D printed scaffold surfaces consisting of pure HA and β-TCP as well as a biphasic mixture of HA and TCP the osteoclastic cell differentiation was studied. In this regard, cell proliferation, differentiation, and activation were analyzed with the monocytic cell line RAW 264.7. The results show that osteoclast-like cells were able to resorb calcium phosphate surfaces consisting of granules. Furthermore, biphasic calcium phosphate ceramics exhibit, because of their osteoclastic activation ability, the most promising surface properties to serve as 3D printed bone substitute scaffolds.

Direct-write assembly of 3D scaffolds using colloidal calcium phosphates inks

“…Nonetheless, the mean compressive strength values of β-TCP (11 MPa) and BCP (15MPa) scaffolds obtained in this study were compatible or higher than that of human trabecular bone. DETSCH et al [18] disclosed that the bone substitute strength should be between 0.5 and 15 MPa, considering a cancellous bone replacement. Studies with trabecular bone have been registered a wide variation of strength which is usually in the range of 4 to 12 MPa [17,19,20].…”

3D Printing of Personalized Artificial Bone Scaffolds

“…This illustrates the influence of phase composition on resorption of ceramic 3D scaffolds. 41 Furthermore, Konopnicki et al 42 fabricated 3DP 50 % PCL and 50 % TCP composite scaffolds seeded with porcine bone marrow progenitor cells (pBMP) and implanted them for 8 weeks into mandibular defects in minipigs. Unseeded scaffolds were used as controls.…”

Nanoscale Bioactive Glass Activates Osteoclastic Differentiation of RAW 264.7 Cells

“…Additionally, 3D cell culture scaffolds composed of biphasic calcium phosphate (BCP) biomaterial, human plasma clots, and RAW 264.7 cells stimulated for 2 days in the presence of a transfected overexpression vector containing a glutathione-S transferase (GST)-RANKL fusion protein demonstrated significantly increased expression of Vegfa and Vegfc compared to untreated controls [11]. When RAW 264.7 cells were cultured in the presence of 3D printed scaffold surfaces, composed of pure HA and β-TCP or a biphasic mixture of HA and TCP (60:40), cellular proliferation and differentiation into TRAP 5b positive stained osteoclast-like cells with resorbing activity occurred [12]. Importantly, an increase of osteoclastic specific genes with expression of various markers (e.g.…”