In-Vitro Mechanical Characterization of Scaffolds for Bone Regeneration Obtained by Stereolithography

Abstract

The medical standard for skeletal fracture treatment has historically been through the use of autografts and allografts. Limitations involving donor availability and increased risks of infection, however, have caused the field of orthopedics to investigate alternatives such as biocompatible scaffolding produced through stereolithography. This study's objective was to characterize the mechanical properties of a biocompatible resin, BioMed Clear, for future use in scaffolding for patients with bone damage. Two samples of BioMed were printed: a porous sample set and a bulk sample set. The porous samples had intricate microstructures similar to those of cancellous bones whereas the bulk samples had compact, solid microstructures which imitate cortical bones. Each sample set underwent aging in a Phosphate Buffered Saline (PBS) for up to thirty days. This process mimics the aging that BioMed will experience after long periods of time within the body. One of four tests was then performed on the specimen�a bending, single-edged notched bending (SENB), compression, or Charpy impact test. Each test served to simulate the conditions of the human body at different times and at different points of stress. This study found that after longer periods of aging, the elastic properties of BioMed decreased while the energy density slightly increased; this was true for both sample types. These trends signify that, over time, BioMed will likely deteriorate within the body. Research on BioMed is ongoing with additional experiments being conducted on samples aged for thirty to ninety days to better understand the material's behavior over extended periods of time.