In the lab, synthetic nanocrystalline bone grafting material in mice has shown in-growth of vascularized fibrous tissue which resulted in improved healing. Furthermore, new blood vessels were observed at day 5 after implantation, and the implant showed a high functional vessel density. In a study examining the femoral epiphyses of rabbits in two to eight weeks of healing, bone-to-implant contact was compared to bone growth inside the chambers for four different implant surfaces. The researchers found that bone substitute materials may improve the bone apposition onto titanium.