Histological evidence of novel ceramic implant: evaluation of tolerability in rabbit femur.

The investigation of desired optimal interface between bone and dental or orthopedic implants, and whether a newly developed material conforms to the requirements of biocompatibility and mechanical stability, are important and rigorous procedures as an essential step prior to clinical trials. The present study proposes the investigation of a novel ceramic implant in terms of biocompatibility, osseointegration and bone response, by an experimental study using a small animal model (rabbit). Radiological examination after six weeks post-surgery highlighted the stability and well integration of the implant, without fibrous tissue or other undesirable complications. The histological analyses highlighted the morphological details of the new tissue, which was well vascularized throughout its thickness. The new bone formation ensured not only the coverage of the implant hole, but also the continuity with the adjacent bone. The chemical stability is suggested by the XRD (X-rays diffraction) pattern, as the implant did not showed erosion marks at the surface, not even discrete ones. Moreover, the XRD pattern recorded on the surface of femoral bone showed the fingerprints of hydroxyapatite indicating that the new bone covered the surface of the implanted area. The qualitative and quantitative aspects of the new bone were highlighted through light microscopy and SEM÷EDX (scanning electron microscopy÷energy dispersive X-rays), especially the lamellar architecture of the new bone at the contact area with the implant, six weeks after insertion. The CA÷P ratio was evaluated, which is a valuable indicator in qualitative assessment of the osseous tissue.