INTEMA   05428
INSTITUTO DE INVESTIGACIONES EN CIENCIA Y TECNOLOGIA DE MATERIALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
The effect of anodised treatment on zirconium implant at early stages:biochemestry and mechanical characterization in an in vivo model.
Autor/es:
TAMARA VICO; MARIA KATUNAR; JOSEFINA BALLARRE; MATIAS BACA; C. VOTTOLA; CERE, SILVIA
Lugar:
Rosario
Reunión:
Congreso; 8vo COLAOB(congreso latinoamericano de organos artificiales, biomateriales e ingenieria de tejido); 2014
Institución organizadora:
COLAOB
Resumen:
Most metals used as cementless implants undergo some kind of surface modification before clinical insertion. These modifications are performed to promote biological reactions at the interface influencing principally in the biological events that lead to bone formation. Cementless prosthesis have been suggested to have the minimal stress shielding and even superior survival rate which make them the primary choice for young patients. Great effort is put into the development of new implants that are designed for better cementless fixation. A variety of surface modifications have been studied and applied to implants to achieve long-term fixation to the host bone by osseointegration It is known that the texturing and /or chemical alterations of material surfaces may lead to long-term integration in bone, so implant topography is critical to the success of bone-anchored implants. Zirconium (Zr) is an ideal metal for intra-osseous implants for its favorable resistance to corrosion, osseointegration capability and lower metal ions migration to the biological surroundings when it is compared with stainless steel and titanium alloys. Zr and its alloys have been studied for being used in the nuclear power industry and have been recently commercialized for its use in medical implants, especially for total knee and hip replacements after hydrothermally grown oxide. The aim of this study is focused on the first events that take place around anodised Zr implants and the biochemistry and mechanical characteristics of the new bone formation. Male Wistar rats were employed and the implants Zr0 (without treatment) and the Zr30 (anodized at 30V) were placed by press fit into tibia extending into the medullar canal. The biological and mechanical events were evaluated 15 and 30 days after surgery. Our results showed that Zr implants had an optimal new bone density distribution, and optimal bone?implant osseointegration both 15 and 30 days after surgery. The thickness of the new bone was evaluated employed Toluidine staining and it showed that anodised treatment improved the characteristic of the new bone growth. The profile of bone formation was analyzed by polychrome fluorescent labeling using calcium-binding fluorochromes that are deposited at the site of active mineralization. When the mineral apposition rate (MAR) is quantified a significant increased over Zr implants 15 days after surgery is found, decreasing 30 days after surgery. The mechanical fixation of Zr implants was also evaluate by push-out test, showing an increased in the mechanical stability and in anodised Zr implants at 15 and 30 days after surgery. In conclusion it is necessary to highlight that just 15 days surgery it is possible to find new bone all around Zr implants and this new bone have excellent mechanical stability. Biochemistry and mechanical assays seem to be improved by anodisation treatment at 30V, suggesting that Zr can be a candidate for permanent implants.