[Bone integration and apposition of porous and non porous metallic orthopaedic biomaterials].

The objective of this study was to evaluate the functionality of two intervertebral fusion implants, a porous nickel-titanium and a conventional titanium cage system in a sheep model. Eighteen sheep each received the two-implant devices at L2-L3 and L4-L5 lumbar levels. The sheep were sacrificed at three different postsurgical periods: three, six and 12 months. Lumbar segments were harvested. Qualitative (macroscopic and microscopic) and quantitative (histomorphometric) histological analysis were carried out on histological slides. The results indicated that a porous nickel-titanium had obtained a better osseointegration than the titanium implant. The functionality of two implants seemed to be influenced by the implant structure and shape. However, biocompatibility of two implants seemed comparable.