Bovine Femur Research Articles

Comparison of the primary stability of orthodontic mini-screws manufactured by the Computer Numerically Control and Selective Laser Melting manufacturing methods: An exploratory study

Background: This study was to assess the primary stability of orthodontic mini-screws of the same design produced by a conventional and a novel manufacturing method. Methods: A total of 150 orthodontic mini-screws with a body length of 8 mm, a diameter of 1.6 mm, a button head, and a self-drilling feature were used in the study. Mini-screws were manufactured through computer numerically controlled (CNC) and selective laser melting (SLM) manufacturing methods. Titanium (T) and stainless steel (SS) alloys were used as manufacturing materials. The study was conducted on three groups; CNC-T, SLM-T and SLM-SS. Mini-screws were placed at 60- and 90-degree angles in fresh bovine femur bones, where the cortical bone thickness was 2 mm. With the radiofrequency analysis (RFA) technique, the stability of the mini-screws was determined immediately after they were placed (F0), immediately after applying orthodontic force to the mini-screw (F1), after six hours (F6), and after 24 hours (F24). Three-way robust ANOVA was used to compare the data, and the Bonferroni correction was statistically applied. Results: Except for the insertion angle of the mini-screw, the group and time factors had statistically significant effects on the RFA values. The highest RFA value was detected in the SLM-T group. Conclusion: Orthodontic mini-screws manufactured from titanium or stainless steel alloys using the SLM technology can be an alternative to mini-screws manufactured using the traditional manufacturing method. The mini-screws manufactured using the SLM technology demonstrated adequate primary stability when subjected to an orthodontic force. Keywords: Orthodontic mini-screw, Primary stability, Selective laser melting, Computer numerical control, Radiofrequency analysis

Nanoarchitectonics for Advancing Bone Graft Technology: Integration of Silver Nanoparticles Against Bacteria and Fungi.

Silver nanoparticles have garnered significant attention for their antimicrobial applications. The aim of this study was to develop and characterize a silver nanoparticle-enhanced bone graft and assess its antimicrobial and antibiofilm activities. Bone granules from bovine cancellous femur were impregnated with silver nanoparticles (50 nm). The antimicrobial and antibiofilm activity was tested against various pathogens, including Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Enterococcus faecalis, Acinetobacter baumannii, and Escherichia coli. Biocompatibility and resorption were evaluated in a mouse calvaria model. All the tested pathogens showed susceptibility to silver nanoparticles, with minimal inhibitory concentrations ranging from 0.25 to 4 mg/L. The silver nanoparticle scaffolds demonstrated a significant reduction in biofilm formation across all microorganisms. The graft exhibited a biocompatibility comparable to that of autologous bone, with reduced resorption rates. Additionally, the presence of nanoparticles did not impact radiolucency, and cytotoxicity remained minimal. Bone grafts impregnated with silver nanoparticles effectively reduce biofilm formation, suggesting their potential as a strategic material for various implant applications.

Application of Reciprocity Principle in Ultrasound Bone Tomography

Abstract Full-matrix synthetic aperture imaging (FMSA) is a well-established and widely used modality for ultrasound imaging Nevertheless, the accompanying relatively large amount of data acquisition, storage, and process results in heavy costs of computation and memory, which further hinders FMSA from real-time implementation. Moreover, the most existing FMSAs employed the hypothesis uniform sound velocity to reconstruct the soft tissues, which is not suitable for hard tissue imaging, irrespective of the high acoustic impedance contrast (i.e., the difference of sound velocity) between the bone and soft tissues. To overcome these limitations, a half-matrix ultrasound bone tomography method combining the reciprocity principle and sound velocity estimation was proposed for cortical cross-section imaging. The travel-time inversion was firstly utilized for sound velocity prediction, and then half-matrix synthetic aperture (HMSA) with ray-tracing was conducted to image the cortical cross-section. An ex-vivo bovine femur was used to validate the effectiveness of the method. Compared to the full-matrix capture method, the proposed method was demonstrated to be an accurate and cost-effective modality for cortical bone tomography.

Effect Gamma-ray on structure and mass attenuation coefficient of Hydroxyapatite Ca10(PO4)6(OH)2, in Bovine Bone

Hydrothermal treatment procedures were employed, to generate hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂ ,(HAP) powder, from the femur and ribs of bovine bone samples. This investigation delves into the effect of gamma rays, from a Cs-137 activity equal to 220 µCi at integral doses of 20 kGy, on the surface structures, vibration properties, and attenuation coefficient of HAP, in the bovine femur bone and ribs. The mass attenuation coefficients for HAP powder were registered as E= 511 keV, with 1276 keV gamma energy released from the 22Na radioisotope, and 662 keV gamma energy released from the 137Cs radioactive isotope. We used the Nist XCom program to calculate the mass attenuation coefficient of HAP before and after radiation for photon energies ranging from 0 keV to 100 keV.

Increased AGE Cross-Linking Reduces the Mechanical Properties of Osteons

The osteon is the primary structural component of bone, contributing significantly to its unique toughness and strength. Despite extensive research on osteonal structure, the properties of osteons have not been fully investigated, particularly within the context of bone fragility diseases like type 2 diabetes mellitus (T2DM). This study aims to isolate osteons from bovine bone, simulate the effects of increased advanced glycation end-products (AGEs) in T2DM through ribosylation, and evaluate the mechanical properties of isolated osteons. Osteons extracted from the posterior section of bovine femur mid-diaphysis were processed to achieve a sub-millimeter scale for microscale imaging. Subsequently, synchrotron radiation micro-computed tomography was employed to precisely localize and isolate the osteon internally. While comparable elastic properties were observed between control and ribosylated osteons, the presence of AGEs led to decreased strain to failure. Young’s modulus was quantified (9.9 ± 4.9 GPa and 8.7 ± 3 GPa, respectively), aligning closely with existing literature. This study presents a novel method for the extraction and isolation of osteons from bone and shows the detrimental effect of AGEs at the osteonal level.

Extracellular matrix coated three-dimensional-printed polycaprolactone scaffolds containing curcumin for cartilage tissue engineering applications

Extracellular matrix (ECM) is widely used for clinical purposes in tissue engineering (TE). Since ECM does not have favorable mechanical properties, its use has been limited. Therefore, it is helpful to use synthetic polymers such as polycaprolactone (PCL) to improve the mechanical properties of ECM-based scaffolds. PCL scaffolds were prepared via the three-dimensional (3D) printing method. Cartilaginous ECM was obtained from bovine femur, and then it was decellularized and solubilized. PCL scaffolds were functionalized using 1,6-hexanediamine; consequently, the scaffolds were coated with solubilized decellularized ECM (SDECM) using two types of crosslinkers; namely, N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) and genipin. Genipin-crosslinked SDECM-coated (PCL/ECM-Gen) scaffolds and EDC/NHS-crosslinked SDECM-coated (PCL/ECM-EN) scaffolds were characterized by different tests. Following loading the curcumin (Cur) on the scaffolds, the Cur release rate was investigated. Finally, human chondrocyte cells were cultured on the scaffolds to explore cell viability, cell attachment, and histological studies. Following functionalization via amine groups, 5% SDECM was used to coat the scaffolds, and this increased the wettability and cell viability of the PCL. Genipin crosslinked and coated the SDECM more efficiently compared to the EDC/NHS and led to lower porosity, water absorption capacity, degradation rate, higher cell proliferation, and cell attachment. Genipin-crosslinked Cur-loaded (PCL/ECM-Gen + Cur) scaffolds showed higher cell viability but lower antibacterial activity compared to EDC/NHS-crosslinked Cur-loaded (PCL/ECM-EN + Cur) scaffolds, which may indicate EDC/NHS-induced cytotoxicity. This study elucidates the value of PCL/ECM-Gen + Cur scaffolds as highly biocompatible scaffolds that can be considered a promising tool for cartilage TE applications.

Effects of bone surface topography and chemistry on macrophage polarization

Surface structure plays a crucial role in determining cell behavior on biomaterials, influencing cell adhesion, proliferation, differentiation, as well as immune cells and macrophage polarization. While grooves and ridges stimulate M2 polarization and pits and bumps promote M1 polarization, these structures do not accurately mimic the real bone surface. Consequently, the impact of mimicking bone surface topography on macrophage polarization remains unknown. Understanding the synergistic sequential roles of M1 and M2 macrophages in osteoimmunomodulation is crucial for effective bone tissue engineering. Thus, exploring the impact of bone surface microstructure mimicking biomaterials on macrophage polarization is critical. In this study, we aimed to sequentially activate M1 and M2 macrophages using Poly-l-Lactic acid (PLA) membranes with bone surface topographical features mimicked through the soft lithography technique. To mimic the bone surface topography, a bovine femur was used as a model surface, and the membranes were further modified with collagen type-I and hydroxyapatite to mimic the bone surface microenvironment. To determine the effect of these biomaterials on macrophage polarization, we conducted experimental analysis that contained estimating cytokine release profiles and characterizing cell morphology. Our results demonstrated the potential of the hydroxyapatite-deposited bone surface-mimicked PLA membranes to trigger sequential and synergistic M1 and M2 macrophage polarizations, suggesting their ability to achieve osteoimmunomodulatory macrophage polarization for bone tissue engineering applications. Although further experimental studies are required to completely investigate the osteoimmunomodulatory effects of these biomaterials, our results provide valuable insights into the potential advantages of biomaterials that mimic the complex microenvironment of bone surfaces.

Osteochondral fluid transport in an ex vivo system

ObjectiveAlterations to fluid transport from bone-to-cartilage may contribute to the development of osteoarthritis. Larger biological molecules found in bone may transport from bone-to-cartilage (e.g., insulin, 5kDa). However, many questions remain about fluid transport between these tissues. The objectives of this study were to (1) test for diffusion of 3kDa molecular tracers from bone-to-cartilage and (2) assess potential differences in bone-to-cartilage fluid transport between different loading conditions. DesignOsteochondral cores extracted from bovine femurs (N=10 femurs, 10 cores/femur) were subjected to either no-load (i.e., pure diffusion), pre-load only, or cyclic compression (5±2% or 10±2% strain) in a two-chamber transport system. The bone was placed into the bone compartment followed by a 3kDa dextran tracer, and tracer concentrations in the cartilage compartment were measured every 5 minutes for 120 minutes. Tracer concentrations were analyzed for differences in beginning, peak and equilibrium concentrations, loading effects, and time-to-peak tracer concentration. ResultsPeak tracer concentration in the cartilage compartment was significantly higher compared to beginning and equilibrium tracer concentrations indicating fluid transport from bone-to-cartilage. Cartilage-compartment tracer concentration, and maximum fluorescent intensity was influenced by strain magnitude. No time-to-peak relationship was found when comparing strain magnitudes impact on cartilage-compartment tracer concentration. ConclusionThis study shows that osteochondral fluid transport occurs from bone-to-cartilage with 3kDa dextran molecules. These are much larger molecules to move between bone and cartilage than previously reported. Further, these results demonstrate the potential for cyclic compression to impact osteochondral fluid transport. Determining the baseline osteochondral fluid transport in healthy tissues is crucial to elucidating the potential mechanisms of progression and onset of osteoarthritis.

In vivo evaluation of a polyester and fiberglass composite intramedullary nail for femoral osteosynthesis in calves.

The objective of this study was to test a composite of polyester resin and fiberglass in the form of an intramedullary nail for osteosynthesis of femoral fractures in calves. The methodology was established based on a previous study that used a bovine femur finite element model to simulate fractures, which were then stabilized by the same nails as proposed in this study. General anesthesia was induced in six calves followed by fracture creation via an oblique incision in the middle third of the femoral diaphysis, and osteosynthesis was immediately performed by retrograde insertion of the composite nail. Locking was achieved by drilling the bone and nail without using a jig and introducing two stainless steel screws proximal and two distal to the fracture line. Five of the six calves achieved complete fracture healing after 60 days. No signs of incompatibility or toxicity of the composite were observed. However, limitations were observed during the surgery, such as difficulty in drilling the nail and trimming the remainder portion of the nail that extended beyond the length of the bone. Small fragments produced by these maneuvers were considered irritating to soft tissues during the postoperative period. It was also found that small cracks in the nail tended to propagate in the form of longitudinal fractures. In conclusion, an intramedullary nail made of polyester resin and fiberglass (a low-cost and easy-to-acquire material) was considered biocompatible and capable of allowing bone healing of femoral fractures in young cattle. However, the development of solutions for the reported limitations is crucial prior to recommending the proposed composite for clinical use.

Comparing the accuracies of freehand, static computer-assisted and robot-assisted dental implant placements: an in vitro study.

To compare the accuracies among three oral implant surgical techniques: freehand (FH), static computer-assisted implant surgery (sCAIS), and robotic computer-assisted implant surgery (rCAIS). The polyurethane and bovine femur implant models were fabricated, and 126 and 96 implant sites were designed on them. The implant sites were divided into three groups: FH, sCAIS, and rCAIS, according to the implantation method. The deviation between the actual implant position and the planned position was analyzed and compared by cone beam computed tomography. In the polyurethane model test, the entry deviation, entry-level deviation, apical deviation, apical level deviation, and angle deviation in sCAIS and rCAIS groups were significantly reduced compared with those in the FH group (P<0.05). No significant differences were observed in all kinds of deviations between the sCAIS and rCAIS groups (P>0.05). In the bovine femur model test, the entry deviation, entry-level deviation, apical deviation, apical level deviation, and angle deviation in both sCAIS and rCAIS groups were significantly reduced compared with those in the FH group (P<0.05). No significant differences were observed in all kinds of deviations between the sCAIS and rCAIS groups (P>0.05). This in vitro study shows that the rCAIS technique is superior to the freehand, but has the same accuracy as the sCAIS.

Comprehensively characterizing heterogeneous and transversely isotropic properties of femur cortical bones

Comprehensive characterization of the transversely isotropic mechanical properties of long bones along both the longitudinal and circumferential gradients is crucial for developing accurate mathematical models and studying bone biomechanics. In addition, mechanical testing to derive elastic, plastic, and failure properties of bones is essential for modeling plastic deformation and failure of bones. To achieve these, we machined a total of 336 cortical specimens, including 168 transverse and 168 longitudinal specimens, from four different quadrants of seven different sections of 3 bovine femurs. We conducted three-point bending tests of these specimens at a loading rate of 0.02 mm/s. Young’s modulus, yield stress, tangential modulus, and effective plastic strain for each specimen were derived from correction equations based on classical beam theory. Our statistical analysis reveals that the longitudinal gradient has a significant effect on the Young’s modulus, yield stress, and tangential modulus of both longitudinal and transverse specimens, whereas the circumferential gradient significantly influences the Young’s modulus, yield stress, and tangential modulus of transverse specimens only. The differences in Young’s modulus and yield stress between longitudinal specimens from different sections are greater than 40%, whereas those between transverse specimens are approximately 30%. The Young’s modulus and yield stress of transverse specimens in the anterior quadrant were 18.81%/15.46% and 18.34%/14.88% higher than those in the posterior and lateral quadrants, respectively. There is no significant interaction between the longitudinal gradient and the circumferential gradient. Considering the transverse isotropy, it is crucial to consider loading direction when investigating the impact of circumferential gradients in the anterior, lateral, medial, and posterior directions. Our findings indicate that the conventional assumption of homogeneity in simulating the cortical bone of long bones may have limitations, and researchers should consider the anatomical position and loading direction of femur specimens for precise prediction of mechanical responses.

Pull-Out Strength of Orthodontic Miniscrews in the Temporal Bone.

Minimally invasive cochlear implant surgery by using a microstereotactic frame demands solid connection to the bone. We aimed to determine the stability of commercially available orthodontic miniscrews to evaluate their feasibility for frame's fixation. In addition, which substitute material most closely resembles the mechanical properties of the human temporal bone was evaluated. Pull-out tests were carried out with five different types of orthodontic miniscrews in human temporal bone specimens. Furthermore, short fiber filled epoxy (SFFE), solid rigid polyurethane (SRPU50), bovine femur, and porcine iliac bone were evaluated as substitute materials. In total, 57 tests in human specimens and 180 tests in the substitute materials were performed. In human temporal bone, average pull-out forces ranged from 220 N to 285 N between screws. Joint stiffness in human temporal bone ranged between 14 N/mm and 358 N/mm. Statistically significant differences between the tested screws were measured in terms of stiffness and elastic energy. One screw type failed insertion due to tip breakage. No significant differences occurred between screws in maximum pull-out force. The average pull-out values of SFFE were 14.1 N higher compared to human specimen. Orthodontic miniscrews provided rigid fixation when partially inserted in human temporal bone, as evidenced by pull-out forces and joint stiffness. Average values exceeded requirements despite variations between screws. Differences in stiffness and elastic energy indicate screw-specific interface mechanics. With proper insertion, orthodontic miniscrews appear suitable for microstereotactic frame anchoring during minimally invasive cochlear implant surgery. However, testing under more complex loading is needed to better predict clinical performance. For further pull-out tests, the most suitable substitute material is SFFE.

Comparative assessment of the physical structure of antler and bovine bone substitutes: An in vitro study.

The use of bone graft materials has significantly increased. Given the inherent variations in structure and functionality between different grafting materials, this evaluated and compared the physical attributes of antler and bovine femur bone substitutes. In the present in vitro investigation, the surface morphological architecture of the two bone substitutes with different origins was assessed through scanning electron microscopy. Furthermore, the Brunauer-Emmett-Teller (BET) technique was employed to measure the porosity, specific surface area (SSA), and pore morphology. Scanning electron microscopy observations indicated that the surface of the bovine particles appeared smoother, while the antler particles exhibited a rougher surface texture. The BET analysis revealed that both samples exhibited identical pore morphology. The SSA was 15.974 m2/g in the antler particles compared with 18.404 m2/g in the bovine sample. The total porosity volume in the antler and bovine femur bone substitutes were 0.2172 cm3/g and 0.2918 cm3/g, respectively. Additionally, the antler particles had a porosity percentage of 40%, whereas the bovine femur bone substitute showed a porosity percentage of 43.5%. Based on the results of this study, it seems that the two samples of bone grafting materials have comparable physical structures.

Can a new cooling method be used in dental implant drilling? An in vitro pilot study

Aims: The aim of this in vitro pilot study was to evaluate the effectiveness of the CryoKB cooling method in increasing the heat-induced temperature during implant drilling in bovine femur bone and to determine its potential usefulness for future in vivo studies. Methods: The study included four groups defined as follows: the G1 group, in which stainless steel materials were cooled using the CryoKB method (n = 13); the G2 group, in which bone was cooled using the CryoKB method (n=13); the K1 group, in which stainless steel materials were cooled using an external irrigation solution (n=13); and the K2 group, in which bone was cooled using an external irrigation solution (n=13). The temperature was measured by creating a 5-mm-deep socket in the bone. The measurements were made every 5 minutes from 0 minutes to 1 hour, using a thermometer device with a type K probe. Results: The temperature changes in 52 samples were evaluated. Statistically significant differences in temperature change were found between the G1 and G2 groups. Statistically significant differences in temperature were found between the G2 and K1 groups and between the G2 and K2 groups. Conclusion: The newly developed cooling method provided more effective and long-lasting cooling than the traditional irrigation method.

Conical shell X-ray beam tomosynthesis and micro-computed tomography for microarchitectural characterisation

Bone quality is commonly used to diagnose bone diseases such as osteoporosis, with many studies focusing on microarchitecture for fracture prediction. In this study a bovine distal femur was imaged using both micro-computed tomography (µCT) and tomosynthesis using focal construct geometry (FCG) for comparison of microarchitectural parameters. Six regions of interest (ROIs) were compared between the two imaging modalities, with both global and adaptive methods used to binarize the images. FCG images were downsampled to the same pixel size as the µCT images. Bone morphometrics were determined using BoneJ, for each imaging modality, binarization technique and ROI. Bone area/total area was found to have few significant differences between FCG and µCT (p < 0.05 for two of six ROIs). Fractal Dimension had only one significant difference (p < 0.05 for one of six ROIs) between µCT and downsampled FCG (where pixel size was equalized). Trabecular thickness and trabecular spacing were observed to follow trends as observed for the corresponding µCT images, although many absolute values were significantly different (p < 0.05 for between one and six ROIs depending on image types used). This study demonstrates the utility of tomosynthesis for measurement of microarchitectural morphometrics.

Antimicrobial Activity of Bovine Bone Scaffolds Impregnated with Silver Nanoparticles on New Delhi Metallo-β-Lactamase-Producing Gram-Negative Bacilli Biofilms

Introduction: The antibiofilm activity of silver nanoparticles has been extensively investigated in common bacteria. Metallo-β-lactamase-producing Gram-negative bacteria are hard-to-treat microorganisms with few therapeutic options, and silver nanoparticles were not evaluated on the biofilm of these bacteria. Objectives: The aim of this study was to evaluate the antibiofilm activity of a bone scaffold impregnated with silver nanoparticles in NDM-producing Gram-negative bacilli. Methods: Bone scaffolds from bovine femur were used for the tests and impregnated with silver nanoparticles (50 nm) by physical adsorption. Silver nitrate minimal inhibitory and bactericidal concentrations (MIC and MBC) were performed on NDM-producing Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Disc diffusion tests for silver nanoparticles’ susceptibility and the quantification of biofilm production on plate and bone with sessile cell count were performed. Results: The MIC results demonstrated that silver nitrate had an antimicrobial effect on all microorganisms, inactivating the growth of isolates from a concentration of 8 µg/mL. MBC results showed that E. coli 16.211 was the only isolate to present MIC that were different from MBC, with a value of 16 µg/mL. Conclusion: Bone scaffolds impregnated with silver nanoparticles can significantly reduce the biofilm of multidrug-resistant bacteria. This is a strategical material that can be used as bone implant in different clinical conditions.

Effect of in vitro ribosylation on the dynamic fracture behavior of mature bovine cortical bone

In this study, the fracture behavior of ribosylated bovine cortical bone is investigated under loading conditions simulating a fall event. Single edge notched specimens, separated into a control group (n = 11) and a ribosylated group (n = 8), were extracted from the mid-diaphysis of a single bovine femur harvested from a mature cow. A seven-day ribosylation process results in the accumulation of Advanced-Glycation End Products (AGEs) cross-links and AGE adducts. Specimens were subjected to symmetric three point bending (opening mode) and an impact velocity of 1.6 m/s using a drop tower. Near-crack displacement fields up to fracture initiation are determined from high-speed images post-processed using digital image correlation. A constrained over-deterministic least squares regression and orthotropic material linear elastic fracture mechanics theory are used to extract the in-plane critical stress intensity factors at fracture initiation (i.e., fracture initiation toughness values). Statistically significant differences were not observed when comparing the in-plane fracture initiation toughness values (p≥0.96) or energy release rate (p=0.90) between the control and seven-day ribosylated groups. The intrinsic variability of bone may require high sample numbers in order to achieve an adequately powered experiment when assessing dynamic fracture behavior. While there are no detectable differences due to the ribosylation treatment investigated, this is likely due to the limited sample sizes utilized.

Nutritional Composition and Anti-Type 2 Diabetes Mellitus Potential of Femur Bone Extracts from Bovine, Chicken, Sheep, and Goat: Phytochemical and In Vivo Studies.

Nutritional deficits in one's diet have been established as the key risk factor for T2DM in recent years. Nutritional therapy has been demonstrated to be useful in treating T2DM. The current study was carried out to assess the nutritional composition of bovine (12 months), chicken (4 months), sheep (13 months), and goat (9 months) femur bone extracts, as well as their potential therapeutic effects on T2DM regression in a Wistar albino rat model (500 mg/kg b.wt.). The proximate composition of the different extracts, their fatty acid composition, their amino acids, and their mineral contents were identified. In vivo data indicated considerably improved T2DM rats, as seen by lower serum levels of TL, TG, TC, ALT, AST, ALP, bilirubin, creatinine, urea, IL-6, TNF-α, sICAM-1, sVCAM-1, and MDA. Low levels of HDL-C, GSH, and total proteins were restored during this study. Histological investigations of liver and pancreatic tissue revealed that the distribution of collagen fibers was nearly normal. The bovine extract, on the other hand, was the most active, followed by the sheep, goat, and finally chicken extract. This research could result in the creation of a simple, noninvasive, low-cost, and reliable method for T2DM control, paving the way for potential early therapeutic applications in T2DM control.

Hydrothermal Extraction and Characterization of Natural Hydroxyapatite from Waste Bovine Femur Bone.

The management of large amounts of bio-wastes, such as bovine femurs from kitchens and slaughterhouses, has long been a challenging issue. However, through the utilization of a hydrothermal process, it is possible to transform these bio-wastes into valuable products. In this study, we focused on extracting hydroxyapatite (HAp), the primary inorganic component of bovine femurs, for potential use in bone tissue engineering scaffolds. By subjecting the femurs to hydrothermal treatment at varying times and solvents, we successfully decomposed and removed the organic matter present, resulting in the extraction of HAp. To comprehensively evaluate the properties of the extracted HAp, we employed several characterization techniques that provided valuable insights into the structure, morphology, and elemental composition of the extracted HAp. Furthermore, we conducted a Cell Counting Kit-8 assay, which confirmed the favorable biocompatibility of the extracted HAp. Overall, this study highlights the potential of hydrothermal treatment as an environmentally friendly and cost-effective method for handling bio-waste, specifically bovine femurs. The extracted HAp exhibits promising characteristics, making it suitable for a wide range of biomedical applications. This research contributes to the sustainable utilization of bio-waste and underscores the importance of resourceful exploitation for environmental protection.

Correlation of the mechanical and structural properties of trabecular bone assessed by wave propagation and imaging methods

This study aimed to assess the correlation of the location- and direction-dependent mechanical and structural properties of trabecular bone using the wave propagation and imaging methods and to propose a non-invasive approach for the assessment of the quality of trabecular bone. Two bovine femur trabecular bone specimens were prepared and tested using the Rayleigh wave propagation tests and CT-scan imaging. The elastic modulus of the specimens was estimated in different regions of interest (ROIs) and wave propagation directions by the solution of the presented Rayleigh wave propagation model. The structural parameters of the specimens were also obtained via the processing of CT-scan images for all of the tested ROIs and directions. The estimated elastic modulus was in the range between 321and 1322 MPa for different ROIs and directions, showing significant heterogeneity and anisotropy of the bone specimens. The Pearson correlation and linear regression analyses were carried out between the obtained mechanical and structural properties, which revealed that the elastic modulus decreased with the trabecular separation and increased with the trabecular thickness and bone volume fraction. A semi-empirical relation was developed to obtain the elastic modulus of trabecular bone using the structural parameters obtained from imaging or vice versa.