PEK and PEEK are thermoplastics with outstanding thermal properties as well as remarkable tensile and compressive strengths. PEEK was invented by the ICI in 1982. There are many industrial and medical uses for the PEEK linear aromatic polymer, and it is also widely considered to be the best thermoplastic material available. PEEK is characterized by its repeating monomers that include two ether and ketone groups. . According to previous studies, PEEK has great potential in dentistry as an additional or alternative material to more conventional metals and ceramics. , . PEEK has been used in a variety of dental devices, including dental implants, healing caps, orthodontic braces, and denture prosthetic frames. . The PEEK's enhanced processing capabilities make it an ideal biomaterial for making a patient-specific prosthesis, which might be a significant potential for the biomaterial. Compared to other polymers, the PEEK polymer exhibits excellent fracture resistance . PEEK composite is utilized in clinical dentistry and orthopedic scaffolds because of its excellent strength-to-weight ratio. PEEK composites low bonding energy has been attributed to their chemical inertness and reduced surface energy .
There has been a dramatic rise in bone fracture and trauma prevalence across industrialized and developing countries over the past several decades. Because of their osteoconductive, osteoproductive, and osteoinductive qualities, bioactive glasses, particularly those based on silica, are poised to play a critical role in this sector. They found that silica and biosilica-rich microspheres were more effective in stimulating bone regeneration than those made of polylactide-co-glycolic acid (PLGA). Using silica- and biosilica-containing microspheres to replace natural bone tissue has been suggested.
In-vitro measurements of CCK-8 cell cytotoxicity and qualitative comparisons of inverted fluorescence microscopy images of cell morphology showed that adding Al2O3 decreased the cell survival of PEEK slightly. A particular surface topography (defined roughness equal to approx. Ra = 0.30 m), which provides the best potential survivability of human osteoblasts, was found in 30 nm Al2O3 reinforced composites. There is evidence that current glass-reinforced PEEK or Ti-6Al-4V manufactured using fast prototyping technology can be utilized to construct implants that can be used in clinical situations . PEEK implants may be improved in cytocompatibility, soft tissue integration, and osseointegration by using TiO2 nanostructure forms .
The 30 wt % HA/PEEK composite was selected in the cytotoxicity experiments. Alkaline phosphatase (ALP) activity was shown to be greater in PEEK composite samples than in UHMWPE and pure PEEK, as evidenced in the cell assays. After seven days of immersion in SBF, the HA/PEEK composite was covered with apatite growth, which continued to grow over extended periods. In animal experiments, there was higher bone contact and bone growth around the HA/PEEK (HA-Hydraxyapatide) composite than around UHMWPE or pure PEEK . The PEEK and CFR-PEEK (CFR- Carbon Fibre Reinforcemnt), were machined and injection moulded, as well as polished (Ra = 0.200microm) and rough (Ra = 0.554microm) cpTi, were all considered. On PEEK (Ra = 0.095microm) and CFR-PEEK (Ra = 0.350microm) injection moulded versions, osteoblast adhesion at 4 hrs was equivalent to titanium. Both PEEK and CFR-PEEK materials were much less machined than their natural counterparts (Ra = 0.902microm and 1.106microm) and determined at 48 hrs. As a result, the maximum thymidine incorporation was found in the injection moulded unfilled PEEK, which was much greater than the rough titanium control . When applied to the PEEK disc implant, the HA coating adhered strongly and formed a homogeneous layer that was simple to clean. Cell adhesion and viability were both increased in early cell adhesion and viability tests performed on the material. It was shown that cells grown on HA-coated PEEK discs had increased ALP activity and calcium concentration, and that they had a higher calcium concentration. The expression of osteoblast development indicators such as ALP, bone sialoprotein, and runt-related transcription factor was also increased in these cells , as well as the expression of other genes. The mesenchymal stem cell proliferation experiment results revealed that the treated layer had more significant cell proliferation when comparing treated and untreated PEEK. The apatite formation data revealed the presence of HA growth on the treated PEEK. However, there was no evidence of HA development on the untreated PEEK even after two weeks of testing .
The success or failure of implants is primarily determined by their ability to integrate with the surrounding bone, which is a significant function of their biocompatibility with the surrounding bone. As a result, nanoparticles of metal oxides have lately become widely employed in composites to improve the topographical and biological characteristics of the materials.
Therefore, the present research aims to develop the functionalized ceramic nanoparticle reinforced PEEK polymer nanocomposite. The acrylic acid-functionalized nSiO2 particles were used as reinforcement and PEEK as a matrix material. The composite was fabricated through the vertical injection moulding process. The morphology of the developed composite sample was investigated using Field Emission Scanning Electron Microscope (FESEM) analysis. The various elements present in the fabricated composite were analyzed using Energy Dispersive X-Ray Analysis (EDAX) and the elemental mapping technique. The material was further characterized with the help of X-ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC) analysis. The biocompatibility of the newly developed nanocomposite has been investigated through the invitro direct and indirect cytotoxicity investigations. Cell viability and cell adhesion studies were carried out to confirm biocompatibility. The MG-63 cell adhesion was investigated using SEM micrographs.