Evaluation Of Degradation Of Bioabsorbable Polycaprolactone Used In Rapid Prototyping For Medical Application

Tissue engineering is an emerging field on regenerative medicine to try to solve the end-stage of organ and tissue failure. This kind of method was developed as an alternative therapy for the treatment of tissue loss or organ failure resolving the shortage on transplantation therapy. Bone and cartilage tissue are under extensive investigation in tissue engineering research. A significant progress has been done on the recent years, although one major obstacle is to maintain the constructed tissue alive in vitro as well as in vivo. For this kind of problem a large number of bioresorbable materials and scaffolds design have been developed. They must have some especial characteristics such as three-dimensional features and highly porous structure with interconnection, biocompatibility and degradation control. Additionally, they shall present suitable surface for attachment of cells, growth and differentiation. Trying to enhance these properties it was used a bioabsorbable polymer approved by the FDA, polycaprolactone. Selective Laser Sintering (SLS) was used with a deflected laser beam selectively to scan over the powder surface following the cross-sequential profiles carried by the slice data. The interaction of the laser beam with the powder elevates the powder temperature to reach the glass-transition temperature, causing surfaces in contact to deform and fuse together. CAD models of different scaffolds were made to evaluate the most commons problems such shrinkage and distortion. In this case we observed oversize of the scaffold walls, reducing the pores size. To evaluate the material degradation rate it was used the SBF solution on 37°C on different times of immersion. After that the samples were weighted and observed on the SEM. We could see a reduction of mass percentage and it was visible bulk degradation of the material on the microscope observation. 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