Comportamento em fadiga de hastes femorais para artroplastia de quadril com superfícies modificadas
Resumen
Nowadays, titanium and its alloys are the materials of choice for the
production of implants for hip arthroplasty, a surgery that aims for the
improvement of the quality of life of patients that bear articular pathologies of the
hip. With the increase of life expectancy, it becomes more and more important
that these implants withstand greater times of implantation, avoiding revision
surgeries, which represent higher costs and risks. Today, this need is approached
by different ways, among them the functionalization of surfaces, that permit better
osseointegration of the prosthesis at the site of implantation and, consequently,
better results on the application of products in the long term. One of the ways to
perform this functionalization is through chemical etching, one of which
(H3PO4+NaOH) has been chosen to perform modification of surfaces previously
treated by titanium plasma spray (TPS+AQ) on finished femoral prostheses. As
a control, another group of prostheses was employed, treated with technology
already in the market, coated by titanium plasma spray with posterior deposition
of two phases of calcium phosphate with different solubility (TPS+HA). The
prostheses were submitted to topographical analyses via SEM, analyses of
roughness profiles and increase of effective surface area by confocal microscopy
and transversal analyses of coatings via SEM, subsequently treated by image
analysis software for determination of attributes of porous coatings according to
ASTM F1854. After that, all prostheses were tested to evaluate their fatigue
behavior according to ISO 7206-4 and the presence of cracks via penetrant liquid
testing. All the specimens survived the fatigue test, refuting the hypothesis that
the modification via TPS+AQ reduces the fatigue resistance of femoral stems
when compared to a control group, TPS+HA, under a normalized test protocol.