3D analysis of bone formation around titanium implants using micro computed tomography (μCT)

The quantitative analysis of bone formation around biofunctionalised metallic implants is an important tool for the further development of implants with higher success rates. This is, nowadays, especially important in cases of additional diseases like diabetes or osteoporosis. Micro computed tomography (ktCT), as non-destructive technique, offers the possibility for quantitative three-dimensional recording of bone close to the implant's surface with micrometer resolution, which is the range of the relevant bony structures. Within different animal models using cylindrical and screw-shaped Ti6A14V implants we have compared visualization and quantitative analysis of newly formed bone by the use of synchrotron-radiation-based CT-systems in comparison with histological findings. The SR mu CT experiments were performed at the beamline BW5 (HASYLAB at DESY, Hamburg, Germany) and at the BAMline (BESSY, Berlin, Germany). For the experiments, PMMA-embedded samples were prepared with diameters of about 8 mm, which contain in the center the implant surrounded by the bony tissue. To (locally) quantify the bone formation, models were developed and optimized. The comparison of the results obtained by SR mu CT and histology demonstrates the advantages and disadvantages of both approaches, although the bone formation values for the different biofunctionalized implants are identical within the error bars. SR mu CT allows the clear identification of fully mineralized bone around the different titanium implants. As hundreds of virtual slices were easily generated for the individual samples, the quantification and interactive bone detection led to conclusions of high precision and statistical relevance. In this way, SR mu CT in combination with interactive data analysis is proven to be more significant(1) with respect to classical histology.