The basic principles behind human tissue response to artificial surface implantation may be developed under its biological aspect, it is necessary for a medical use to study the mechanical limits of every biomaterials to predict the tissue and the body's response according to the composition, the structure and the design of a biomedical material. To promote a stable and functional direct connection between bone and implant, titanium implants can be coated with materials based on calcium phosphate ceramics such as hydroxyapatite (HAp)(Ca10(P04)6(OH)2). The preferred orientation of HAp crystallites at the interface bone-implant in sheep tibia bones has been measured with the neutron 2-axis diffractometer D20 at the Institut Max von Laue-Paul Langevin (ILL), extracted 60 days after implantation. The implant has two faces, one coated and one non-coated with plasma-sprayed HAp (80 .m). We probed the samples with a spatial resolution of 0.5 mm started from the interface in order to inspect the reorganisation of the HAp crystallite’s distribution after implantation.