PREPARATION AND METHODS FOR SEQUENTIAL EVALUATION OF TITANIUM IMPLANT INTERFACES IN PLASTIC-EMBEDDED CALCIFIED BONE

Clinical, radiographic, fluorescence, histological, and electron microscopy techniques can be utilized for a comprehensive examination of bone/implant interfaces. To accomplish this objective, proper fixation, processing techniques, instrument quality control, and laboratory safety practices should be followed at all times. This paper reviews the methodology that has become standard practice in our laboratory for the evaluation of bone/implant interfaces. A regimen of fluorescent bone markers was used after implant placement to study rates of bone remodeling. At sacrifice, the tissue was perfused or immersed in an aldehyde or alcohol fixative. Implants were retrieved en bloc, radiographs made, and tissues embedded in plastic. Tissue implant blocks were cut longitudinally into 300-400 mu m thick wafers with a low speed saw equipped with a diamond blade. The wafers were glued to plexiglass slides and hand ground to approximately 25 mu m. Wafers were photographed with an epi-fluorescence microscope; radiographs were made in an X-ray cabinet; and the sections were stained for light microscopy evaluation. Various histomorphometric methods can be used to determine some variables of tissue remodeling around the implants from photomicrographs. Specimens prepared in this fashion can also be evaluated with a scanning or transmission electron microscope. These combined techniques provide a comprehensive approach for the evaluation of the bone/implant interface.