In vitro osteoconductivity of PMMA-Y2O3 composite resins

Polymethyl methacrylate (PMMA) bone cements are used as “glue” between orthopedic/orthodontic implants and bone, since they can be modeled and easily applied by the surgeon, while being chemically and biologically stable for many years after surgery. In this research, Y₂O₃ powder was added to commercial PMMA bone cement to produce a composite resin, which was then characterized and tested in vitro to evaluate the cell proliferation and the quality of osteoblastic bone formed in vitro on the composite. Biological assays showed an increase in cell proliferation on the Y₂O₃-PMMA composite as compared to the pristine sample. Alizarin Red staining (ARS) showed the amount of bone formed on a composite PMMA resin was about 30% higher than that on the pristine PMMA bone cement reference. The quality of bone tissue was evaluated using Raman spectroscopy, showing the bone tissue formed on the composite had a better degree of mineralization and a higher maturity as compared to the tissue grown on the control sample. These preliminary results suggest that Y₂O₃ plays a biologically active role in bone growth and Y₂O₃-composites are affordable, superior candidates as bone cement materials.