Investigation on the physical properties and biocompatibility of zirconia-alumina-silicate@diopside composite materials and its in vivo toxicity study in embryonic zebrafish

The Influence of Cuprorivaite Nanoparticles on the Physicomechanical and Biological Performance of 3D-Printed Scaffold Based on Carboxymethyl Chitosan Combined With Zein for Bone Tissue Engineering

This study demonstrates a new degradable 3D-printed carboxymethyl chitosan (CMC)/zein bone scaffold loaded with different content of cuprorivaite (Cup) nanoparticles which labeled as CMCS/Z/Cup. Only a few studies have utilized these components to fabricate a three-component porous osteogenic scaffold. The aim of this study was to comprehensively assess the mechanical and biocompatibility of the nanocomposite which synthesized by 3D printing method. For this purpose, the Cup powder was initially synthesized through sol-gel process and its confirmation was proved using techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Then, three CMC/Z scaffolds were made with different Cup contents: group A (0 wt.% Cup), group B (2.5 wt.% Cup) and group C (5 wt.% Cup). The scaffolds were well-ordered microporous with a high porosity and pore connectivity, as observed by morphological analysis by SEM. Additionally, the pore size of group B was more homogeneous than that of groups A and C. There were no significance differences in physicochemical characterization among the three groups. Mechanical properties analysis showed that values of compression modulus are significantly increased with addition of 2.5% Cup nanoparticles into CMCS/zein matrix, from 1.2 to 9.6 MPa. The incorporation of Cup nanoparticles into CMCS along with zein can provide a suitable substrate for the growth of osteoblast cells after implantation, as indicated by the results of in vitro degradation. The scaffolds were cultured in vitro with MG-63 cells, showing that cell viability increased with the Cup content, 95%, 105%, and 110% for the pure polymeric scaffold, and scaffolds reinforced with 2.5% and 5% Cup, respectively. As a result, the scaffolds designed in this study possess the ability to be used in bone tissue engineering due to having characteristics similar to natural bone.

An Experimental Parametric Optimisation for Laser Engraving and Texturing to Integrate Zirconia Ceramic Blocks into Stainless Steel Cutlery: A State-of-the-Art Aesthetically Improved Perspective

Cutlery and flatware designs are an everchanging phenomenon of the manufacturing industry. Worldwide hospitality businesses demand perpetual evolution in terms of aesthetics, designs, patterns, colours, and materials due to customers' demands, modernisation, and fierce competition. To thrive in this competitive market, modern fabrication techniques must be flexible, adoptive, fast, and cost effective. For decades, static designs and trademark patterns were achieved through moulds, limiting production to a single cutlery type per mould. However, with the advent of laser engraving and design systems, the whole business of cutlery production has been revolutionised. This study explores the possibility of creating diverse designs for stainless steel 304 flatware sets without changing the entire production process. The research analyses three key laser process parameters, power, scanning speed, and number of passes, and their impacts on the resulting geometry, depth of cut, surface roughness, and material removed. These parameters are comprehensively studied and analysed for steel and zirconia ceramic. The study details the effects of power, scanning speed, number of passages, and fluence on engraved geometry. Fluence (power*number of passages/scanning speed) positively influences outputs and presents a positive trend. Medium power settings and higher scanning speeds with the maximum number of passages produce high-quality, low-roughness optimised cavities with the ideal geometric accuracy for both materials.

Amorphous, Carbonated Calcium Phosphate and Biopolymer-Composite-Coated Si3N4/MWCNTs as Potential Novel Implant Materials

A biodegradable amorphous carbonated calcium phosphate (caCP)-incorporated polycaprolactone (PCL) composite layer was successfully deposited by a spin coater. In this specific coating, the PCL acts as a bioadhesive, since it provides a better adherence of the coatings to the substrate compared to powder coatings. The caCP-PCL coatings were deposited and formed thin layers on the surface of a Si3N4-3 wt% MWCNT (multiwalled carbon nanotube) substrate, which is an emerging type of implant material in the biomedical field. The composite coatings were examined regarding their morphology, structure and biological performance. The biocompatibility of the samples was tested in vitro with MC3T3-E1 preosteoblast cells. Owing to the caCP-PCL thin layer, the cell viability values were considerably increased compared to the substrate material. The ALP and LDH tests showed numerous living cells on the investrigated coatings. The morphology of the MC3T3-E1 cells was examined by fluorescent staining (calcein and DAPI) and scanning electron microscopy, both of which revealed a well-spread, adhered and confluent monolayer of cells. All performed biocompatibility tests were positive and indicated the applicability of the deposited thin composite layers as possible candidates for orthopaedic implants for an extended period.