12 déc
12/12/2019 10:00

Sciences & Société

Soutenance de thèse : Alethea LIENS

On the potential of Ti-based Bulk Metallic Glasses and Ce-TZP zirconia composites for the development of innovative dental implants

Doctorante : Alethea LIENS

Laboratoire INSA : MATEIS
Ecole doctorale : ED34 : Matériaux de Lyon

Recently, dental implant downsizing has become one major trend in modern implantology but it requires the development of materials with improved mechanical resistance. Titanium and its alloys, the gold standard dental materials, seem to have reached a plateau in terms of mechanical properties, which may limit their use for such strategy.
Amorphous titanium-based metallic alloys are a class of materials showing unique mechanical properties, which make them potential candidates for the realization of small diameter implantable pieces.
There is also a growing trend to use ceramic implants in dentistry. In particular, the white color of Yttria-Tetragonal Zirconia Polycrystal (Y-TZP) materials combined with their unique transformation toughening ability have made them materials of choice for the realization of metal-free, aesthetic dental implants. However, ageing of Y-TZP ceramics in aqueous environments may be a concern and even if strongest than many other ceramics, Y-TZPs still remains sensitive to the presence of defects. Various Ceria-doped based zirconia ceramics (Ce-TZP) have been developed over the past years and have shown a high resistance to flaws, a considerable toughness and an unusual transformation-induced ductility, which make them potential candidates for the realization of ceramic dental implants, as an alternative to 3Y-TZP. Within this PhD work, the potential of two materials for (i) the realization of less invasive implants to replace titanium alloys on one hand, and (ii) aesthetic and more reliable ceramic implants as alternative to 3Y-TZP on the other hand, will be studied.
The first part of this work will be focused on Ti40Zr10Cu36Pd14 metallic glass. The second part of this work will deal with a new Ce-TZP based composite. Mechanical characterizations combined with biocompatibility assessment, corrosion resistance evaluation and tests on real size dental implants have been performed.All the results may open new perspectives in the future of dental applications.