Skyscan 1176 x ray microtomography

All animal procedures were approved by the Animal Ethics Committee of Huazhong University of Science and Technology (HUST). Three-month-old female Sprague Dawley rats were purchased from the Tongji Experimental Animals Center, Tongji Medical College of HUST and the experiments performed according to the recommendations of the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. To generate the osteoporosis model, rats were subjected to bilateral ovariectomy (OVX) or sham operation (Sham). Three months after ovariectomy, the femurs were explanted from OVX and Sham groups and scanned on a micro-computed tomography (micro-CT) imaging system (SkyScan 1176 X-ray microtomography; Bruker, Billerica, MA, USA). Sections in the femoral condyle were chosen and a series of slices starting at a distance of 1 mm proximal to the end of the growth plate with a length of 2 mm were selected for evaluation. The following parameters were analyzed for each group (n=3) using the CT-analyzer software: bone volume fraction (bone volume [BV]/tissue volume [TV]), trabecular number (Tb.N), trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp).

The specimens were scanned on a micro-CT scanner (SkyScan 1176 X-ray microtomography; Bruker, Billerica, MA, USA) at a resolution of 18 μm to assess bone regeneration at the defect site on the cranium. After 3D reconstruction, CT-analyzer software (Bruker, Billerica, MA, USA) was used to analyze the bone mineral density (BMD) and the percentage bone volume (bone volume/tissue volume, BV/TV) (n = 5).