Redes epóxi/amina alifáticas com perspectivas para aplicações cardiovasculares. Propriedades biológicas in vitro

Este trabalho descreve as propriedades biológicas in vitro de três redes epoxídicas à base do éter diglicidílico do glicerol (DGEG) curadas com poli(oxipropileno) diamina (D230), isoforona diamina (IPD) e 4,4'-diamino-3,3'-dimetil-diciclohexilmetano (3DCM). As interações biológicas entre os polímeros e o sangue foram estudadas por ensaios biológicos in vitro. Estudos de adsorção de proteínas, adesão de plaquetas, atividade do lactato desidrogenase (LDH) e propriedades de tromboresistência estão apresentados. Os ensaios de adsorção de proteínas na superfície dos polímeros mostrou que as redes epoxídicas adsorvem mais albumina do que fibrinogênio. Os resultados relacionados à adesão de plaquetas, atividade do lactato hidrogenase e propriedades de tromboresistência indicaram que as redes DGEG/IPD e DGEG/3DCM exibem comportamento hemocompatível. Desta maneira, assumimos que estes polímeros epoxídicos são materiais compatíveis com o sangue

Examination of mechanical properties of bovine femurs

Celem badania było określenie własności mechanicznych bydlęcych kości udowych w różnym stanie uwodnienia i wysuszenia. Wartości te są niezbędne do numerycznych i eksperymentalnych analiz układu kość-implant, prowadzonych podczas projektowania nowych rozwiązań konstrukcyjnych. Dla celów pracy przeprowadzono statyczną próbę zginania i pomiary twardości oraz prowadzono obserwacje makroskopowe obszarów pęknięcia próbek.The aim of this study was to determine the mechanical properties of bovine femur. Those values are necessary for numerical and experimental analyses of the bone-implant system, conducted during designing new structural solutions for this system. For the purpose of work the static bending test and hardness measurement were performed

Evaluation of Corrosion Resistance of Titanium Alloys Used for Medical Implants

The study presents the results of investigations of modeling the usable properties of implant surfaces made of Ti6Al7Nb alloy, using the example of a dynamic hip screw (DHS) applied in surgical treatment of intertrochanteric femoral neck fractures. Numerical simulation has been performed for the model load of femoral fixation with DHS screw. The load simulation results provided the basis to select mechanical properties of the fixator elements and to define those fixation areas which are mostly susceptible to development of corrosion. The surfaces of Ti6Al7Nb alloy were ground, vibro-abrasive machined, mechanically polished, sandblasted, anode oxidized at different voltage values and steam sterilized. Results of surface topography evaluation, resistance to pitting and crevice corrosion as well as degradation kinetics of the outer layer were presented. Usability of the formed passive layer in clinical applications was evaluated through wear and corrosion tests of the femoral fixation model. The test results proved usefulness of the proposed surface modification methods for clinical application of different size and shape implants