Nondestructive three-dimensional evaluation of biocompatible materials by microtomography using synchrotron radiation

Abstract

Microtomography based on synchrotron radiation sources is a unique technique for the 3D characterization of different materials with a spatial resolution down to about 1 tm. The interface between implant materials (metals, ceramics and polymers) and biological matter is non-destructively accessible, i.e. without preparation artifacts. Since the materials exhibit different X-ray absorption, it can become impossible to visualize implant material and tissue, simultaneously.Here, we show that coating of polymer implants, which are invisible in bone tissue, does not only improve the interfacial properties but also allow the imaging of the interface in detail. Titanium implants, on the other hand, absorb the X-rays stronger than bone tissue. The difference, however, is small enough to quantify the bone formation near interface. Another advantage of microtomography with respect to classical histology is the capability to examine samples in a hydrated state. We demonstrate that ceramic hollow spheres can be imaged before sintering and fibroblasts marked by 0504 are visible on polymer textiles. Consequently, scaffolds of different materials designed for tissue engineering and implant coatings can be optimized on the basis ofthe tomograms.

Three-dimensional quantification of capillary networks in healthy and cancerous tissues of two mice

“…Using a photon energy of 10 keV, a pixel size of 1.98 μm and an exposure time of 5.85 s, 1440 radiographs equidistantly acquired along 360°with an asymmetric rotation axis (Müller et al, 2007) were combined to 720 radiographs used for data reconstruction. The spatial resolution determined from the 10% value of the modulation transfer function corresponded to 4.7 μm (Müller et al, 2002a). The X rays were converted to visible light by means of CdWO 4 scintillator with a thickness of 200 μm.…”

Wood-Derived Porous Ceramics via Infiltration of SiO2-Sol and Carbothermal Reduction

“…At a photon energy of 13 keV and a spatial resolution of 3.5 µm (Müller et al 2002a) 4 scans were necessary to scan the whole cylindrical shaped sample with a diameter of 2 mm and a height of 8 mm. At a photon energy of 13 keV and a spatial resolution of 3.5 µm (Müller et al 2002a) 4 scans were necessary to scan the whole cylindrical shaped sample with a diameter of 2 mm and a height of 8 mm.…”

Understanding Nano-Anatomy of Healthy and Carious Human Teeth: a Prerequisite for Nanodentistry

“…The radiographs were binned by a factor of two before reconstruction to improve the photon statistics and thereby the contrast [43]. The spatial resolution of the entire experimental setup was determined by the 10% value of the modulation transfer function of a radiograph from a highly X-ray absorbing edge [44]. It corresponded to 4.2 and 6.2 lm, respectively.…”