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Singh Stougaard
Singh Stougaard

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Nanopore-based desalination be subject to concurrently employed force slope along with gating prospective.

Bone mineral densitometry (BMD) showed significance between the FSAG (p = 0.009) and TFS (p = 0.007) groups. The bone mineral content (BMC) presented a significant difference between all groups (p = 0.020). Maximum strength showed a significant difference between the FSAG group (p = 0.007) and the others. The results obtained in relation to the relative stiffness also present a significant difference (p = 0.023). Newly formed bone showed significant differences between groups (p = 0.035). We conclude that bone defect regeneration was directly influenced by the use of FS and AG. In the present paper, a computational finite element analysis (FEA) was developed by using the COMSOL Multiphysics® software to evaluate the thermal accumulated stress on a 3-unit dental ceramic pressed over metal (POM) bridge, at different cooling rates during the glaze treatment. The cooling rates are related to the free opening of the furnace at 800 °C (extreme case) and the restricted opening when the restoration reaches 450 °C (slow case). The thermal expansion coefficients of the materials and the glass transition point of the ceramic were measured experimentally using a dilatometer test. The FEA was performed based on the ceramic temperature profile, which was determined experimentally by using thermocouples type K. When the dental ceramic reaches its transition temperature (Tg) at 510 °C, maximum principal stress at the grooves from the occlusal surface of the pontic are reported as 140 MPa for the slow and 400 MPa for the fast cooling rate. Additionally, it is demonstrated that stresses can be reduced by using low Young's modulus metals and with small differences in the material's thermal expansion coefficient (CTE). PURPOSE To synthesize a zirconia-toughened alumina (ZTA) composite with 85% alumina matrix reinforced by 15% zirconia and to characterize its optical and mechanical properties before and after artificial aging, to be compared with a conventional dental zirconia (3Y-TZP). MATERIAL AND METHODS After syntheses, ZTA and 3Y-TZP powders were uniaxially and isostatically pressed. Green-body samples were sintered and polished to obtain 80 disc-shaped specimens per group (12 × 1 mm, ISO 68722015). The crystalline content and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). Optical properties were determined by the calculation of contrast ratio (CR) and translucency parameter (TP) using reflectance data. Mechanical properties were assessed by Vickers hardness, fracture toughness and biaxial flexural strength test (BFS). All analyses were conducted before and after artificial aging (20h, 134 °C, 0.22 MPa). Optical parameters and microhardness differences were evaluatedhigh-stress mission (800 MPa) a significant decrease in probability of survival was observed for aged 3Y-TZP (84%) and for immediate and aged ZTA (73 and 82% respectively). CONCLUSION The ZTA composite presented a dense microstructure, with preservation of the crystalline content, optical and mechanical properties after artificial aging, which encourages future research to validate its potential use for large span FDP. The innovative design of orthopedic implants could play an important role in the development of life-lasting implants, by improving both primary and secondary implant fixations. MT-802 nmr The concept of meta-biomaterials aims to achieve a unique combination of mechanical, mass transport, and biological properties through optimized topological design of additively manufactured (AM) porous biomaterials. In this study, we primarily focused on a specific class of meta-biomaterials, namely auxetic meta-biomaterials. Their extraordinary behavior of lateral expansion in response to axial tension could potentially improve implant-bone contact in certain orthopedic applications. In this work, a multitude of auxetic meta-biomaterials were rationally designed and printed from Ti-6Al-4V using a commercially available laser powder bed fusion process called selective laser melting. The re-entrant hexagonal honeycomb unit cell was used as a starting point, which was then parametrically tuned to obtain a variety of mechanical and morpted properties like these could be used to simultaneously address the different challenges faced in the mechanical design of orthopedic implants. Polylactic acid (PLA) is a biodegradable, biocompatible and non-toxic biopolymer with good mechanical properties, and is commonly used for the additive manufacture of PLA-based biomedical devices. Such devices are available in a range of sizes and thicknesses, with smaller devices capable of being realised via additive manufacturing in just a few layers. Due to their thermal history and thermal degradation, the thermal, molecular weight and mechanical properties of each layer was different when the raw material was melted, and the in-course layer was deposited to the previous layer. This study investigated the effect of the number of layers on mechanical, thermal and molecular weight properties, and the relationship between them. Material extruded ISO 527-2 type 5A specimens with 1-, 2-, 3-, 4-, 5-, 7- and 10-layers were prepared with the cutting die. Results indicated that the degree of crystallinity was found to decrease from 8% to 0.5% with an increasing number of layers. This was likely due to different cooling rates, where the molecular weight was lowest for 1-layer and increased with the increasing number of layers until it almost reached that of the bulk material. Additionally, ultimate tensile strength and strain increased with an increasing number of layers, while Young's Modulus decreased due to heterogeneous material structure. Of all obtained results, there was no significant difference between 5- and 10-layer in terms of mechanical and thermal properties. This study describes a mathematical model for bone remodeling that integrates the bone cells activities with the pharmacological dynamics for bone-seeking agents. The evolution of bone cells population involves the osteoblast-osteoclast signaling mediated by biochemical factors and receives both mechanical stimulus evaluated at the microscale and pharmacological regulation. A physiologically based pharmacokinetic model (PBPK) for bone-seeking agents was developed to provide the drug concentration on bone sites and feed the remodeling algorithm. The drug effect on bone was reproduced coupling three different strategies modification of the RANKL expression, increase the osteoclast apoptosis and change in the rate of differentiation of preosteoblasts. Computational simulations were performed in the PBPK model considering different dosing regimens. A 3D finite element model of a proximal femur was generated and the simulation of the bone remodeling algorithm were implemented in Matlab. The results indicate that the proposed integrated model is able to capture adequately the expected adaptive behavior of bone subjected to mechanical and pharmacological stimulus.MT-802 nmr

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