Nanostructural interface and strength of polymer composite scaffolds applied to intervertebral bone

The pores of bone tissue that play an important part in bone regeneration can emulate the areas of nanoparticles from porous scaffolds. This work evaluated a novel designed and developed nanostructure surface of polyetheretherketone-reduced graphene oxide, calcium hydroxyapatite (PEEK-rGO-cHAp) composite scaffolds of four different lattice structures. The scaffolds were fabricated through fused deposition modeling (FDM), as rGO-cHAp composite was coated on PEEK. The composite scaffolds’ mechanical strength and surface microstructure were studied, using different nanostructure methods of unit cell homogenization and tensile test. The homogenization method for the four lattice structures was designed and analyzed to mimic spine bone structure. A new approach was introduced to homogenize the mechanical characteristics of a periodical lattice of 3D printing structures based on a semi-rigid frame unit cell. They were taking into consideration the impact of geometric approximation errors and joint tightening. A typical frame element with semi-rigid is integrated to assess combined stiffening effects in a discrete homogenization process. The analysis was performed by considering the fundamental unit cell as a scaffold that defined the periodic pattern. Also, this study created an avenue to examine and improve the interfacial bonding between PEEK and rGO-cHAp scaffolds for biocompatibility and degradability, using surface functionalization techniques. The purpose of this research is to compare the manufacturing processes in a model of intervertebral spacer, describe the characteristics of PEEK biomaterial, and explain some parameters related to its processing. In addition to its manufacturing part, a brief theory on the anatomy of the spine region was also presented. To establish its practical applications and benefits in tissue engineering, this study focused on the cervical region via a simulation approach using an anterior method.</p

3D printing of PEEK–cHAp scaffold for medical bone implant

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.The major drawback associated with PEEK implants is their biologically inert surface, which caused unsatisfactory cellular response and poor adhesion between the implants and surrounding soft tissues against proper bone growth. In this study, polyetheretherketone (PEEK) was incorporated with calcium hydroxyapatite (cHAp) to fabricate a PEEK–cHAp biocomposite, using the fused deposition modeling (FDM) method and a surface treatment strategy to create microporous architectures onto the filaments of PEEK lattice scaffold. Also, nanostructure and morphological tests of the PEEK–cHAp biocomposite were modeled and analyzed on the FDM-printed PEEK–cHAp biocomposite sample to evaluate its mechanical and thermal strengths as well as in vitro cytotoxicity via a scanning electron microscope (SEM). A technique was used innovatively to create and investigate the porous nanostructure of the PEEK with controlled pore size and distribution to promote cell penetration and biological integration of the PEEK–cHAp into the tissue. In vivo tests demonstrated that the surface-treated micropores facilitated the adhesion of newly regenerated soft tissues to form tight implant–tissue interfacial bonding between the cHAp and PEEK. The results of the cell culture depicted that PEEK–cHAp exhibited better cell proliferation attachment spreading and higher alkaline phosphatase activity than PEEK alone. Apatite islands formed on the PEEK–cHAp composite after immersion in simulated body fluid of Dulbecco's modified Eagle medium (DMEM) for 14 days and grew continuously with more or extended periods. The microstructure treatment of the crystallinity of PEEK was comparatively and significantly different from the PEEK–cHAp sample, indicating a better treatment of PEEK–cHAp. The in vitro results obtained from the PEEK–cHAp biocomposite material showed its biodegradability and performance suitability for bone implants. This study has potential applications in the field of biomedical engineering to strengthen the conceptual knowledge of FDM and medical implants fabricated from PEEK–cHAp biocomposite materials

Lattice design and 3D-printing of PEEK with Ca10(OH)(PO4)3 and in-vitro bio-composite for bone implant

© 2020 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/.The addition of biomaterials such as Calcium hydroxyapatite (cHAp) and incorporation of porosity into poly-ether-ether-ketone (PEEK) are effective ways to improve bone-implant interfaces and osseointegration of PEEK composite. Hence, the morphological effects of nanocomposite on surfaces biocompatibility of a newly fabricated composite of PEEK polymer and cHAp for a bone implant, using additive manufacturing (AM) were investigated. Fused deposition modeling (FDM) method and a surface treatment strategy were employed to create a microporous scaffold. PEEK osteointegration was slow and, therefore, it was accelerated by surface coatings with the incorporation of bioactive cHAp, with enhanced mechanical and biological behaviors for bone implants. Characterization of the new PEEK/cHAp composite was done by X-ray diffraction (XRD), differential scanning calorimetry (DSC), mechanical tests of traction and flexion, thermal dynamic mechanical analysis (DMA). Also, the PEEK/cHAp induced the formation of apatite after immersion in the simulated body fluid of DMEM for different days to check its biological bioactivity for an implant. In-vivo results depicted that the osseointegration and the biological activity around the PEEK/cHAp composite were higher than that of PEEK. The increase in the mechanical performance of cHAp-coated PEEK can be attributed to the increase in the degree of crystallinity and accumulation of residual polymer.Peer reviewe