Histological and Synchrotron Radiation-Based Computed Microtomography Study of 2 Human-Retrieved Direct Laser Metal Formed Titanium Implants

Background:The macroscopic structure of bone has been traditionally studied through x-ray radiography or x-ray tomography. However, the resolution limits of these techniques do not enable the reconstruction of the composite bone architecture at the nanometer level. Compared with histomorphometry, x-ray micro-CT has shown its efficiency in providing nondestructive and rapid 3D images and measurements on bone microstructure. Micro-CT higher resolution has been achieved with synchrotron radiation-based computed microtomography (SR&mgr;CT). Purpose:The aim of this study was a histological and SR&mgr;CT analysis of 2 porous titanium implants. Materials and Methods:Two direct laser metal forming titanium implants were inserted in the posterior maxilla of a patient and retrieved after 2 months. One of these implants was treated to obtain thin ground sections, whereas the other underwent a SR&mgr;CT evaluation. Results:The histological results, showing that the implant surface presented superficial debris and particle inclusions in the surrounding tissue close to the bone area, were confirmed by micro-CT investigations. Conclusions:SR&mgr;CT allowed high resolution with good sample penetration and depth of focus and an evaluation of the relative arrangement of structures that cannot be determined by 2D imaging.