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Bone fracture due to internal or external factors is one of the most common diseases in today's orthopedic society. One of the techniques to solve these problems is to use artificial porous bone grafts made by 3D printers and the Freeze-Drying (FD) techniques. In this study, a shapeless porous scaffold was first fabricated using Fused Deposition Modeling (FDM) with the electroconductive filament. The printed scaffold is inserted into the alginate solution composed of Magnetite Nanoparticles (MNPs) containing 0, 10, 20, and 30 wt% baghdadite nanoparticles. Then, the four samples are coated using an FD technique at −45 °C and 0.01 m bar. The mechanical and biological properties are investigated using compressive strength and Simulated Body Fluid (SBF) test. The samples are analyzed using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) analysis to evaluate the morphology and phase of the fabricated specimens. The obtained results from the measurement of mechanical properties show that the scaffolds can maintain their strength in the dry state and terms of mechanical properties close to cortical bones at about 6.5 MPa for the sample with 20 wt% and 72% porosity. The swelling behavior of the scaffolds in the Phosphate Buffer Saline (PBS) is also investigated. The cytotoxicity of the porous scaffold is evaluated by direct measurement for three days and the result of the sample with 20 wt% was significantly better than the other samples. Finally, this research shows that the produced bio-nanocomposite scaffolds have potential application in tissue engineering.

In recent decades, polymer composites are widely used in industry due to their good mechanical properties and their low specific weight. Also, the use of glass fibers and carbon nanotubes can strengthen and improve the mechanical performance of the polymer due to their good mechanical properties. In this study, incorporated glass/epoxy nanocomposite with carbon nanotubes (CNT) samples were fabricated using a hand lay-up process, and the effect of addition functionalized Single-Walled Carbon Nanotubes (F-SWCNT) with COOH and non-functionalized SWCNT was investigated. The tensile strength, elastic modulus, bending strength was obtained experimentally using SANTAM-STM50. X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) were used to investigate the phase and morphology of the fibers. The mechanical properties results showed that the highest elastic modulus and tensile strength are obtained for the sample reinforced with F-SWCNT which increased by 32% and 10%, respectively in comparison with pure epoxy. Also, the obtained results of the bending test indicate that the highest flexural modulus and the highest flexural strength are related to the sample reinforced with functionalized carbon nanotubes which are 16.9 GPa and 381.39 MPa, respectively. Then, the mechanical performance of the reinforcement in the epoxy matrix and the failure mechanism was monitored using SEM images. Finally, reinforced epoxy nanocomposites with functionalized and non-functionalized SWCNT were simulated using Molecular Dynamics (MD) simulation to examine the agreement with the trends of experimental results. The MD obtained results showed that the most appropriate mode of dispersion occurs when functionalized carbon nanotubes are used. Also, it was observed that the elastic modulus of incorporated nanocomposites with F-SWCNT increased by 17% compared to non-functionalized SWCNT which shows the agreement with the trends of experimental results.

In this work, a novel porous bio-nanocomposite material containing the commercial nanocrystalline hydroxyapatite (n-HA) composed using single-walled carbon nanotubes (SWCNTs) with different weight fractions (0, 2.5, 5, and 7.5 wt%) is fabricated via a space holder technique for bone tissue engineering applications. The hydroxyapatite (HA) presents a weak mechanical performance which the addition of the SWCNT can enhance the mechanical strength of the matrix. The manufactured n-HA-SWCNT bio-nanocomposite samples are then coated by gelatin-ibuprofen (GN-IBO) bio-polymer with a dip-coating method. The X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) are employed for the phase characterization and surface morphology analysis of the fabricated bio-nanocomposite specimens. The mechanical properties, the rate of drug release, and biological characteristics of the specimens with and without SWCNTs are investigated. After that, the nonlinear instability and vibration responses of an axially loaded plate-form bone implant made of the manufactured n-HA-SWCNT bio-nanocomposite samples coated with GN-IBO thin layers are simulated through a sandwich-plate model and based upon the experimentally extracted mechanical properties. The obtained results indicate the presence of SWCNT and n-HA in the composition due to the fuzzy metamorphism or degradation. It is found that by increasing the amount of SWCNTs, the mass density of the fabricated bio-nanocomposite samples reduces, but the porosity and strength of them are higher than those of the pure n-HA. Therefore, it is expected that these newly manufactured bio-nanocomposites have an excellent capability for bone formation with better bonds with surrounding tissues.

The cancerous bone may be treated using magnetite nanoparticles (MNPs) coupled with hyperthermia treatment technology. During the last three decades, calcium-silicate (CS) based bioceramics have been investigated as a proper choice due to their bioactivity, biocompatibility, magnetization property, and ability to form suitable apatite for hard tissue engineering approaches. For this purpose, three-dimensional bio-nanocomposite scaffolds utilizing bioactive wollastonite (WS) and bioglass (BG) as composed based materials with 0 wt% (S1), 5 wt% (S2), 10 wt% (S3), and 15 wt% (S4) of Zr–Fe3O4 are considered in this study. These materials with two various space-agents such as sodium chloride (NaCl) and sodium bicarbonate (NaHCO3) particles containing ball mill with high energy and pressing under 150 MPa, and sintered at 850 °C are analyzed. Additionally, X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating-sample magnetometer (VSM), and mechanical tests include of toughness and compressive strength are investigated. The powder's and scaffold's crystals size are measured between 30 and 50 nm, and the pores and porosity size are measured from 70 to 180 μm and 25%–40%. The VSM curves illustrate that the zirconium-ferrite has a soft magnetic property, which is easily magnetized by applying a small amount of magnetic field, and it rapidly loses its magnetic moment by cutting off the field. The low coercive force, as well as high magnetic saturation with low residue, are represented for the S2 and S3. The obtained outcomes indicate that the best amounts of mechanical properties amongst the specimens are related to the specimen with 15 wt%, 7.9 ± 1 MPa of compressive strength, and 203.3 ± 10 MPa of elastic modulus. Likewise, the biological assessment shows that the sample containing 10 wt% MNPs provides a better apatite creation on porous scaffolds after 28 days. The gained outcomes represent that those specimens containing 10 and 15 wt% MNPs provide proper biological and mechanical replies.

The multiscale nanocomposites are a new class of the designed materials that have nano and micro-scale reinforcements. The main purpose of this paper is to investigate the mechanical properties suc...

With the aid of fast development in manufacturing techniques, it is now possible to produce structures with considerable geometrical complexity. In the current investigation, 3D printing machine is utilized to produce beam-type bone implant made of porous polymers with three different periodic cellular topologies. The stress-strain curves and mechanical properties of the bone implants are extracted experimentally corresponding to each porosity shape with various pore sizes. Scanning electron microscope (SEM) is utilized to assess the biological capability in apatite formation on the free surface of the fabricated scaffolds after soaking in the simulated body fluid (SBF). Thereafter, based upon the obtained mechanical properties and using generalized differential quadrature (GDQ) method, the nonlinear primary resonance of bone implants made of the polymer scaffolds and subjected to the soft harmonic excitation is predicted corresponding. The frequency-response and amplitude-response of the bone implants are presented associated with the cubic, spherical and honeycomb periodic cellular topologies and different pore sizes. The analysis of soaked samples in SBF reveals that among different porosity shapes, the samples with cubic and hexagonal porosities have the maximum and minimum permeability, respectively. However, this pattern is vice versa for apatite formation. Moreover, it is seen that for the samples with cubic and hexagonal porosity shapes, the oscillation amplitude as well as the associated excitation frequency at the peak of jump phenomenon are maximum and minimum, respectively.

Scaffold creates a chance for bone growth and facilitates cell adhesion, growth and differentiation in orthopedic surgeries. Designing scaffold with adequate porous geometry and suitable compressive strength is debatable among biomaterial engineers and clinical orthopedic surgeons. Therefore, in this study we fabricate a novel porous hydroxyapatite-wollastonite reinforced with 0, 5, 10, and 15 wt% alumina nanoparticles (ALN: 40–80 nm) for bone substitute. In the current work, a porous cylindrical scaffold (6 mm × 10 mm) fabricated with space holder (SH) technique using sodium bicarbonate (NaHCO3) as a porous agent. The porosity, compressive strength and the biological behavior of the porous samples were investigated using standard mechanical and biological testing. After making the specimen, scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis were performed to verify the accuracy of the nanomaterial's properties. The mechanical and biological analysis (swelling & water absorption) showed that the sample with 10 wt% alumina nanoparticles (ALN) had both proper compression strength vs. porosity percentage and bioactivity response. The molecular modeling for predicting the elastic modulus of bio-nanocomposite were performed and the results were close to the experimental values. The obtained result, indicated that compressive strength increased from 2.8 to 3.5 MPa with 49% to 61% porosity value. The sample with 10 wt% ALN and wollastonite showed clinical applications of these composites as a bone-substitute.

In the current study, hydroxyapatite (HA)-MgO scaffolds are fabricated with the aid of the space holder technique using NaCl as the spacer type. After that, the fabricated samples are deposited in gelatin (GN) with ibuprofen (IBO) substitution to create GN-IBO thin surface coating. The samples are then synthesized chemically and the associated properties are studied using X-ray diffraction (XRD) and scan electron microscopy (SEM) equipped with the energy dispersive spectroscopy (EDS). The compressive strength, fracture toughness, hardness, porosity, bioactivity, degradation rate, wettability, and roughness of the manufactured HA-MgO bio-nanocomposite scaffolds containing different weight fractions of MgO nanoparticles are predicted. Accordingly, nonlinear mechanical behaviors including nonlinear free vibration and nonlinear vibrations associated with the prebuckling and postbuckling domains of an axially loaded plate-type bone implant made of the HA-MgO bio-nanocomposites coated with the GN-IBO thin layers are investigated analytically via a sandwich plate model. The obtained results reveal that magnesium has no considerable effect on the porosity, however it causes to enhance the compressive strength significantly. The presence of magnesium ions also leads to reduce the crystallinity of HA about 30–100 nm due to entering MgO nanoparticles into the network. The results related to the sample with 10 wt% MgO nanoparticles indicate that the microscopic structure of the fabricated bio-nanocomposite scaffold is three-dimensional with porous architecture. Also, it is shown that the solubility of the HA composed with MgO nanoparticles decreases with higher bioactivity.

In the present work, bioactive nanoclay-TiO2 (NC-T) bio-nanocomposite scaffolds containing different TiO2 weight fractions are fabricated spacer for bone tissue engineering applications via the space holder technique using NaCl particles as the. The microstructure, surface morphology (porosity) and bioactivity potential of the manufactured bio-nanocomposite scaffolds are examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF), energy dispersive spectroscopy (EDS), and inductively-coupled plasma optical emission spectroscopy (ICP-OES) techniques. The scaffold with optimized mechanical properties is predicted as NC-15wt%T with proper interconnected porosity and micro/macro pore size within the range of 1–2 (μm) and 3–5 (μm), respectively. Also, its mechanical properties including compressive strength, elastic modulus and crystallite size are extracted equal to 5.74 MPa, 438 MPa and 70–120 nm, respectively. The feasibility of the fabricated scaffolds for bioactive bone tissue engineering application (apatite deposition) is also evaluated using simulated body fluid (SBF) and physiological saline (PS) solutions. At the end, the nonlinear bending and vibration characteristics of an axially loaded beam-type bone implant made of the NC-T/NaCl bio-nanocomposite scaffolds are predicted analytically. In general view, the obtained results indicate that the NC-15wt%T/NaCl bio-nanocomposite scaffold may have excellent advantages for future research in bone regenerative applications.

Having excellent biocompatibility and apatite mineralization as well as efficient mechanical properties makes bredigite as one of the most attractive bioceramics. A beam-type porous biological implant in a 3D-printed architecture is designed with micron pore size. The surface properties, morphology, and size of the composed powders are evaluated using Scherrer and Williamson-Hall equation. The effect of MNPs deposition into the bredigite bioceramics and correlation with temperature effect on roughness of the prepared bio-nanocomposite are also investigated for hyperthermia application potential. The composed powders are characterized by x-ray diffraction, and then scanning electron microscopy (SEM), differential scanning calorimetry, thermogravimetric analysis (weight change, TGA), and atomic force microscopy are utilized to evaluate the surface topography. The resonance response is the tendency of a bone scaffold to respond at prominent amplitude while the frequency of its oscillations is equal to the structure’s natural frequency of vibration. Therefore, based on the obtained mechanical properties via the experimental approach for the bio-nanocomposite material, an analytical solution based upon the multiple-timescale method is carried out to analyze the nonlinear primary resonance of a 3D-printed porous beam-type biological implant under uniform-distributed load. According to SEM observations, there are hard agglomerates in the bredigite-magnetite nanoparticles (Br-MNPs) bio-nanocomposite material with low weight fraction of MNPs. However, they are broken down by increasing the amount of MNPs. Also, it is displayed that for lower MNPs weight fraction, the height of jump phenomenon related to the nonlinear resonance response is maximum and minimum for, respectively, irregular and mesoporous shapes of morphology, but their associated forcing amplitudes related to the bifurcation points are minimum and maximum, respectively.

Due to the Si-O-Si bonding, silicate bioceramics have enhanced mechanical characteristics than their calcium phosphate (CaP) counterparts. Bredigite with orthorhombic crystal system is one of the most efficient bioceramics in osteoblast and bone growth. On the other hand, biosilicate-magnetite composites (e.g. bredigite-magnetite and hardystonite-magnetite) are excellent candidates for hyperthermia applications. In the current study, the vibrational response of a beam-type bone implant subjected to axial compression is investigated. The implant is made of bredigite-magnetite bio-nanocomposite scaffold fabricated by 3D printing machine including 0.8 mm pore size. The Young's modulus of the scaffold is extracted experimentally corresponding to different magnetite nanoparticle (MNP) weight fractions, crystalline nanocomposite particle size, and various shapes of morphology. The morphology shape is determined corresponding to different MNP weight fractions and temperatures using scanning electron microscopy (SEM). Thereafter, an analytical solution is presented to express explicitly the load-frequency and frequency-deflection responses of the axially loaded beam-type bone implant. It is observed that in the prebuckling domain, by increasing the axial compressive load, the influence of the MNP weight fraction on the natural frequency of the bio-nanocomposite implant increases while in the postbuckling regime, increment in the axial compression has no effect on the significance of the MNP weight fraction effect.

Magnetite is a bioresorbable material that has been widely employed in bioengineering domain, drug-delivery operations, and hyperthermia treatment. In the biomedical engineering, the major focus is on the mechanical properties of materials used in orthopedic and dental implants. In the present investigation, beam-type bone implant made of bredigite composed with magnetite nanoparticles (MNPs) is fabricated with a customized three dimensional (3D) printing, the nonlinear bending and postbuckling behaviors of it are studied. To accomplish this purpose, the Young's modulus of the prepared bio-nanocomposite material is obtained experimentally corresponding to different MNP weight fractions and sizes of the nanoparticles as well as their morphology shapes. In order to prepare the bio-nanocomposite material, the planetary high energy ball milling (HEBM) is put to use to mix the bredigite bioceramic powder as a bioactive matrix with various weight fractions of MNPs. After that, based upon a developed analytical solution, the nonlinear bending and instability response of the bio-nanocomposite beam-type bone implant are analyzed corresponding to various MNP weight fractions and morphology shapes of the material. It is found that for the bio-nanocomposite implant with smaller composite crystallite size, the maximum and minimum buckling loads are for irregular and mesoporous morphology shapes, respectively. On the hand, for the bio-nanocomposite bone implant with larger composite particle size, the maximum and minimum buckling loads are related to, respectively, the spongy and porous morphology shapes.

Although, the ideal hard ferromagnetic particles are much better energy absorbers as against the ideal superparamagnetic particles, the use of hard ferromagnetic materials in hyperthermia applications has always been a major challenge for researchers due to their high anisotropy. This work introduces a route to use a hard magnetic material (SrFe12O19) in the form of nanoparticle and scaffold in hyperthermia application. Single domain SrFe12O19 nanoparticles, with a hard magnetic behavior, when composited with hydroxyapatite (HA), allowed the use of the minimum frequency and amplitude of the alternative magnetic (AC) field to have high amount of specific absorption rate. This was the outstanding advantages of this work, especially when a monodispersed HA-SrFe12O19 nanocomposite was used. HA-10 wt%SrFe12O19 scaffolds, after gelatin coting, showed a high stable compressive strength with a high uniform interconnected porosities. Besides, HA-10 wt%SrFe12O19 composite nanoparticles showed a high specific absorption rate in both mono and multi dispersed states.

In the present study, the 3D printer method for fabricating porous bone scaffolds with Polylactic Acid (PLA) printed was used by Fused Deposition Modelling (FDM). Then, the prepared 3D scaffold coated with alginate composed with various amounts of Hydroxyapatite (HA) using the freeze-drying technique. After the fabrication of novel functional graded materials scaffold, the mechanical strength and biological behavior were investigated. The Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) analysis used to characterize the morphology and phase characterization. The structure of the porous scaffold was simulated using the ABAQUS analysis method and their mechanical and physical properties were extracted. Also, strong antibacterial properties were observed for all samples with increasing HA nanoparticles against gram-positive and gram-negative bacterial suspensions. These bio-nano composites are compatible with the pH of the blood. In general, it was found that the most suitable bio-nano composite is the sample with 10 wt % HA nanoparticles. The elastic modulus increased from 350 MPa to 394 MPa with the addition of HA nanoparticles, while the porosity percentages decreased from 44 % to 36 %. The compressive strength increases from 25.2 MPa to 32.7 MPa with the addition of 30 wt% HA nanoparticles. The obtained results showed that the bio-nano composites prepared in this study were suitable for further development in bone substitutes with desirable mechanical properties. The alginate/HA material properties reported from the numerical approach, have an acceptable agreement with experimental results. Furthermore, the numerical study indicated that the scaffold compressive strength increases from 22.8 MPa (S1) to 31.2 MPa (S4) with the addition of 30 wt % HA nanoparticles. Nanoindentation test explains that the indenter penetration decreases from 82.163 nm to 69.338 nm with the addition of 30 wt% HA nanoparticles. As a consequence, PLA-alginate/20 wt % HA (S3) and, PLA-alginate/30 wt% HA (S4) have the best mechanical properties. Although due to lower biological advantages of S4 concerning S3, PLA-alginate/20 wt % HA (S3) chose as an appropriate bio-nanocomposite for orthopedic application.

The aim of this study is to evaluate the hyperthermia application of a novel bredigite-magnetite nanocomposite for bone tissue engineering. Magnetite nanoparticles were synthesized by the co-precipitation method and then composited with bredigite powders via a mechanical milling route and subsequent sintering process. Bredigite-Magnetite nanocomposite possessed a homogeneous dispersion of magnetite nanoparticles, which was confirmed by the absence of large aggregates. To evaluate the heat release of the composite nanoparticles, an alternating magnetic (AC) field was applied. The results showed an increase in the temperature, as a result of the increasing magnetite concentration. The sample containing 30 wt.% magnetite particles showed a temperature increase about 27 °C during 50 s. Generally, the present work confirmed that the bredigite-magnetite nanocomposite can be considered as an assuring candidate in hyperthermia applications.

In the current study, bio-nanocomposites scaffolds including natural hydroxyapatite (n-HA) composed with different weight fractions of copper oxide nanoparticles (CuO-NPs) are fabricated using the space holder technique. After that, the manufactured samples are coated with gelatin polymer loaded with ibuprofen drug. Via experimental methods, the mechanical properties (fracture toughness and compressive strength) of n-HA-CuO bio-nanocomposite scaffolds are achieved corresponding to various weight fractions of the CuO-NPs. Also, the electrical conductivity and cell viability of the fabricated scaffolds are evaluated using the scan electron microscope (SEM) and X-ray diffraction (XRD) technique. Thereafter, based upon the extracted mechanical properties, nonlinear mechanical behaviors of beam-type implants made of the prepared n-HA-CuO bio-nanocomposites are predicted analytically. The cell viability and electrical conductivity evaluation demonstrate that on the free surface of all bio-nanocomposite scaffolds, there is a thin layer of apatite carbonate; however, the thickness of this layer in the sample containing 5wt% CuO-NPs is lower than other ones. It is seen that the adherence of ibuprofen's penetration into the gelatin polymer is weak which leads to two explosive release stages. For the lower weight fraction of CuO-NPs, the release of ibuprofen becomes significant.

In order to achieve more efficient additive materials having precise desired porosities with excellent performance, advanced manufacturing techniques can be put to use. In the present study, 3D printing technology is employed to fabricate mesoporous bioceramic-based bony scaffolds made of various periodic cellular topologies including cubic, cylindrical and hexagonal porosity configurations. The samples are composed of polylactic acid-hydroxyapatite (PLA-HA) mesoporous bioceramic-based nanocomposites. Via the respective experiments, the mechanical properties of the fabricated bony scaffolds are extracted corresponding to each porosity configuration with different pore sizes. Moreover, by using the scanning electron microscopy (SEM), X-ray diffraction (XRD) and the permeability characteristics of the fabricated bio-composite samples after soaking in the simulated body fluid (SBF) are captured. Thereafter, based on the experimentally obtained mechanical properties, the multiple time-scales method is utilized to develop an analytical solution for the nonlinear secondary resonance of PLA-HA mesoporous beam-type implants under subharmonic and superharmonic excitations. The frequency-response and amplitude response associated with the both types of hard excitations are depicted corresponding to different periodic cellular topologies and pore sizes. It is observed that among various periodic cellular topologies, the gap between two branches of the subharmonic frequency-response associated with the cubic and hexagonal ones is maximum and minimum, respectively. In the case of superharmonic excitation, it is found that through reduction of the pore size, the peak of frequency-response and its associated value of the detuning parameter decrease.

Introduction: Advantages of using porous bio-nanocomposite scaffolds for maxillofacial fracture application and optimizing the internal surfaces of synthetic grafts using nanotechnology can accelerate the bone cell adhesion, mechanical properties and absorption rates. There are various studies that have been performed on porous scaffold, especially for the fractured and destroyed parts of the facial bones. The aim of this study was to investigate the experimental and numerical analysis of the porous scaffold, which undertakes static and dynamic loading conditions. Materials and Methods: The maxillofacial bone was modeled using the solid works software, and then it was inserted into the Abaqus software to achieve a more precise model that utilizes an isotropic linear substance. Thereafter, a proper micromechanical model reported evaluating the elastic modulus response on porosity value using various models. Additionally, an experimental analysis was conducted on a new calcium silicate (CS) bioceramic reinforced with magnetite nanoparticles (MNPs) using the space holder technique coated with the gentamicin drug loaded on gelatin polymer. The response of the bio-nanocomposites shape, which corresponds to different MNPs’ weight fractions, was determined using the scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. Results: The analysis of the scaffold implant showed that it is tightened at a torque of stiffness of 3 mm in the implant, which leads to high mechanical tension. The results showed that the elastic modulus of the nanocomposites increased from 60±5 MPa to 145±5 MPa with increasing 15 wt% MNPs to the calcium silicate nanoparticles. Conclusion: The results indicated that addition of 15 wt% MNPs to the based bioceramics increased both compression strength and decrease the porosity value.

Post-surgical infection is one of the essential problems in bone scaffolds that is usually treated with antibiotics. This issue may be related to the poor blood supply for bone tissue due to high concentrations of drug. In the current study, the effect of zinc oxide (ZnO) nanoparticles on the antibacterial behavior of the nanocrystalline hydroxyapatite (n-HA) scaffolds coated by gelatin-ibuprofen (GN-IBO) is evaluated. To this end, the bio-nanocomposite scaffolds are fabricated via the space holder technique and then characterized with the aid of X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The compressive strength, fracture toughness, porosity, elastic modulus as the mechanical properties, and the apatite formation, biodegradation, drug release and wettability beside the roughness as the biological properties are predicted. The obtained experimental results indicate that the bio-nanocomposite scaffolds containing 10 wt% ZnO has suitable mechanical and biological properties. After that, an analytical model is developed to predict the nonlinear instability and vibration responses of an axially loaded sandwich plate-type implants made of the fabricated n-HA-ZnO bio-nanocomposites coated by GN-IBO thin film corresponding to various weight fractions of ZnO nanoparticles. It is found that ZnO peaks in the positions of 2θ are equal to 31.6 ° , 33.6 ° , 34 ° , 46.4 ° , and 62 ° , which represent the crystalline characteristics. Also, it is revealed that through addition of ZnO nanoparticles, the hardness and elastic modulus as well as the bone formation and biodegradation rate of the bio-nanocomposite scaffold enhance, while its drug release in the phosphate buffer solution detected with UV spectrum reduces. It is found that by increasing the ZnO weight fraction, the critical axial buckling load of the sandwich bio-nanocomposite implant enhances, and it buckles at lower axial shortening. However, it is seen that for higher value of wt% ZnO, its influence on the critical buckling load decreases.

Iranian Gum Tragacanth (IGT) is among the most natural polymers which has interesting properties such as nontoxic nature, biodegradability and high resistance to bacterial attacks making it applicable for tissue scaffolds, protective clothing, and wound healing. In the current work, polyvinyl alcohol (PVA)/IGT nanocomposite fibre is prepared by using the electrospinning (ELS) technique in an aqueous solution with different volume ratios of 60/40, 70/30, 80/20, and 90/10. To enhance the chemical and mechanical stability of the produced samples, different amounts of nanoclay powder (1% and 3%) are added also to the solution. The blended nanofibres are characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), and bioactivity evaluation in phosphate buffered saline (PBS) and simulated body fluid (SBF) solutions. The FTIR analysis indicated that PVA and IGT may have H + bonding interactions. The results revealed that with a higher amount of IGT, a superior degradation as well as a higher chemical and biological stability could be obtained in the nanobiocomposite blend fibres. Furthermore, the blend nanofibre samples of 80/20 and 3% nanoclay powder exhibit a significant improvement during evaluation of its properties.

In the presented study, the deposition of nanostructured NHA-Di (natural hydroxyapatite-diopside) composite coatings on the surface of Ti-6Al-4 V implants is studied. The effect of electrophoretic deposition (EPD) voltage, Di content and process temperature on the surface roughness is also investigated. The powders are characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray fluorescence (XRF). The atomic force microscopy (AFM) is also used to study the surface topography. According to SEM observations, there are hard agglomerates in the NHA-Di composite powders at low percentage of Di; however they are broken down by increasing the amount of Di percentage. Images which were obtained from the 2D AFM analysis of the NHA-Di coating after its deposition on Ti alloy specimen surface, indicated that the “Roughen” diagram fluctuates between the range of −0.03 and 0.01 μm under the conditions that the Di content reaches 30 wt%. A specific load is applied during the adhesion test which resulted in NHA-30 wt% Di coating maintain its impeccability while the NHA-0 wt% Di coating samples were damaged.A graph is also developed based on the Hertz stress which proved to be challenging in terms of chemical stability based on its surface roughness.

Since hydroxyapatite-based materials have similar composition and crystallinity as natural calcified tissues, can be used for bone/tissue engineering. In the present study a novel nanocomposite based on bioceramics such as Natural Hydroxyapatite (NHA) and Baghdadite (BAG), was sintered by spark plasma sintering (SPS) technique. The prepared composite was characterized using scanning electron microscopy (SEM), X-ray diffractometer (XRD) and Brunauer–Emmett–Teller (BET) techniques. The porosity of the samples was measured by Archimedes method. The cold crushing strength (CCS) test was applied to evaluate their mechanical properties. Our results demonstrated that NHA-30wt. %BAG nanocomposite specimens have the lower CCS in comparison with other examined composites. Consequently, NHA/BAG samples exhibited acceptable mechanical properties and could be suitable candidates for bone tissue engineering applications especially orthopaedic fields.

In the present study, diopside nanopowders were prepared via mechanical milling with eggshell as the calcium source. The space holder method (compaction of ceramic powder and spacer) as one of the most important methods to produce ceramic/metal scaffolds was used to produce diopside scaffolds. For the first time, the effect of the spacer size on mechanical properties and porosity of the obtained scaffolds was experimentally discussed. According to the results obtained, the NaCl particles (as the spacer) with the size of 400–600 µm maintained their original spherical shape during the compaction and sintering processes. As a new work, the most important parameters including the spacer type, spacer concentration, spacer size, and applied pressure were considered, and their effects on mechanical properties and porosity of diopside scaffolds were simulated. Gene Expression Programming (GEP), as one of the most branches of the artificial intelligence, was used for simulation process. By using the GEP, two equations were introduced to predict the compressive strength and porosity of the obtained scaffolds with the lowest error values. The 3D diagrams extracted from the model were used to evaluate the combined effect of the process parameters on the compressive strength and porosity of the scaffolds. The GEP model presented in this work has a very low level of error and a high level of the squared regression for predicting the compressive strength and porosity of diopside scaffolds.

The surface characteristics of implant which influence the speed and strength of osseointegration include surface chemistry, crystal structure and crystallinity, roughness, strain hardening, and presence of impurities. The aim of this study was to evaluate the bioactivity and roughness of a novel natural hydroxyapatite/zircon (NHA/zircon) nanobiocomposite, coated on 316L stainless steel (SS) soaked in simulated body fluid (SBF). NHA/zircon nanobiocomposite was fabricated with 0 wt.%, 5 wt.%, 10 wt.%, and 15 wt.% of zircon in NHA using ball mill for 20 minutes. The composite mixture was coated on 316L SS using plasma spray method. The results are estimated using the scanning electron microscopy (SEM) observation to evaluate surface morphology, X-ray diffraction (XRD) to analyze phase composition, and transmission electron microscopy (TEM) technique to evaluate the shape and size of prepared NHA. Surfaces roughness tester was performed to characterize the coated nanocomposite samples. The maximum averageRa(14.54 μm) was found in the NHA 10 wt.% of zircon coating. In addition, crystallinity (Xc) was measured by XRD data, which indicated the minimum value (Xc = 41.1%) for the sample containing 10 wt.% of zircon. Maximum bioactivity occurred in the sample containing 10 wt.% of zircon, which was due to two reasons: first, the maximum roughness and, second, the minimum crystallinity of nanobiocomposite coating.