Endosseous implant optimization:from implant surface modifications to bone regeneration

Replacing one or several missing teeth, whether for reasons of pathology or trauma, has become very common. A system of artificial roots are inserted and integrated in the mandible or the maxilla to support fixed or removable restorations. The implant has to be mechanically stable, and integrated into the bone in order to mediate and distribute, as physiologically as possible, the biomechanical stresses applied to the system tooth-bone, a phenomenon called osseointegration. The success of a good osseointegration is multifactorial, including the materials properties (chemical, physical mechanical and structural), the implant design, the surgical techniques, the pathophysiological context and the bone health and quality. During our research, we focused on two particular issues: 1- The materials “ surface characteristics », and more specifically the surface chemistry of endosseous implants on which we applied various thin metallic coatings. 2- The « health and bone quality » by developping innovative materials for bone regeneration. We demonstrated that TiNxOy coatings may be applied to various metallic substrates to improve their osseointegration, allowing the use of materials more efficient mechanically, beyond their native biocompatibility. On the other hand, we also developed an innovative bone substitute by using 3D-printing processes. This material, structurally highly organized, may lead to an osseoconduction rate (i.e. the capacity for a structure to conduct bone cells migration and growth) that is largely superior to actual standards. This material is also resorbable, and may support the development of a mature bone tissue. These works open a broad range of perspectives both in the basic science and in the applied science, including, as for example, a better understanding of the molecular mechanisms of osseointegration, or the development of hybrid materials combining cells, bioceramics and hydrogels in a prevasscularized osseoconductive structure