Papers by Keyword: In Vitro Tests

Abstract: The aim of this study was to evaluate the biocompatibility of Al₂O₃-Ti functionally graded material (FGM) successfully fabricated by Spark Plasma Sintering (SPS) technology, and to compare with pure Ti and alumina. Pre-osteoblast MC3T3-E1 cells were used to examine cell viability, proliferation and differentiation using lactate dehydrogenase (LDH) cytotoxicity detection kit, MTT assay and Alkaline Phosphatase (ALP) colorimetric test at different time points. Furthermore, ion release from the materials into the culture medium was assessed. The results showed cell viability over 80% for FGM and alumina which dismissed any cytotoxicity risk due to materials or manufacturing. The results of MTT tests identified superiority of FGM than Ti and alumina, particularly in late proliferation. Nevertheless, in cell differentiation, all materials performed similarly with no statistical differences. Furthermore, it was indicated that Ti had no ion release, while alumina had small amount of Al ion dissolution. FGM, however, had more ions detachment, particularly Al ions.

Abstract: This Chapter is focused on the Ti-Nb-based shape memory alloys for biomedical applications; the principal objective being to understand interrelations between structure and transformation features, static and dynamic functional properties, and conditions of their thermomechanical treatment. This Chapter includes also preliminary study of the surface characteristics of Ti-Nb-based alloys, including their elemental and phase compositions, tribological characteristics, wettability, electrochemical behaviour, and in vitro biocompatibility. The results obtained make it possible to conclude that Ti-Nb-based shape memory alloys represent one of the strongest candidates for a new generation of load-bearing orthopaedic or dental implants with improved biocompatibility, since they combine high biomechanical compatibility of Ti-Ni shape memory alloys with excellent biochemical compatibility of pure titanium.

Abstract: The knowledge of the degradation process is an important role to understand and predict in vitro results. Granules of strontium-hydroxyapatite (Sr-HA) were submitted to a degradation process under dynamic conditions using a bioreactor system and using a solution with pH=5. The degradation process under dynamic conditions can be represented by a curve in which the calcium content firstly increases (dissolution part) followed by calcium decreasing (reprecipitation). The use of a low pH solution does not affect the curve’s shape but reduces the precipitation step.

Abstract: Mineralization experiments on glasses of the Si-Ca-P-Mg system were carried out for 7 days in carbonated simulated inorganic plasma (CSIP) buffered with CO2/HCO3 -. This method enables physiological buffering of the solution within the 7.3–7.4 pH interval by maintaining a HCO3 - concentration between 24 and 27 mmol.L-1, which is the normal concentration range in blood plasma. XRD, SEM/EDS and FTIR were used to characterise the glass surfaces. All glasses exhibited an apatite-like deposit whose Ca/P ratio was dependent on glass composition.