INVESTIGADORES
KATUNAR Maria Rosa
congresos y reuniones científicas
Título:
The effect of anodized on zirconium implant at early stages:biochemistry and mechanical characterization in an "in vivo" model
Autor/es:
TAMARA VICO; MARIA R. KATUNAR; JOSEFINA BALLARRE; MATIAS BACA; CARLOS V. VOTTOLA; SILVIA CERE
Reunión:
Congreso; 8 Congreso Latinoamericano de Organos Artificiales, Biomateriales e Ingenieria de tejidos COLAOB 2014; 2014
Resumen:
THE
EFFECT OF ANODISED TREATMENT ON ZIRCONIUM IMPLANT AT EARLY STAGES: BIOCHEMISTRY
AND MECHANICAL CHARACTERIZATION IN AN IN VIVO MODEL
Tamara Vico1, Maria R. Katunar1,Josefina
Ballarre1, Matias Baca2, Carlos B. Vottola2,
and Silvia Cere1
1 INTEMA. Universidad Nacional de Mar del Plata
(UNMdP)-CONICET
2Hospital Interzonal General de Agudos (HIGA) Oscar Alende, Mar del Plata,
Argentina.
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 biological
structure 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