Behavior of the bone–titanium interface after push‐in testing: A morphological study

Abstract Fourteen titanium dental implants (Tioblast™) were implanted singly in the proximal tibia of New Zealand rabbits for 120 days. A bone defect was surgically produced and filled with Bio‐Oss^® around six of these implants. After the animals were sacrificed and their organs harvested, bone segments were fixed and methacrylate embedded after the push‐in test had been performed. Microradiography was performed on longitudinal sections of the implants, whereas scanning electron microscope analysis was performed on the remaining embedded half‐implants using secondary electrons only. The results showed that the implants were apically and coronally surrounded by bone, whether Bio‐Oss^® was used or not. Fractures were evident through the newly formed bone and between the pre‐existing and newly formed bone. Some fracture lines propagated through the bone and stopped at the implant surface without continuing along the bone–titanium interface. Detachment between the implant and the bone occurred at the coronal extremity of the implants and along its cervical region. These results highlight the fact that the bone–titanium interface has a high resistance to loading. It exhibited greater resistance than the newly formed bone and seems to behave in a manner similar to the cement lines of osteons. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 64A: 365–371, 2003