Background
Implants or implantable devices should integrate into the host tissue faster
than fibrous capsule formation, in which the design of the interface is one
of the biggest challenges. Generally, bioactive materials are not viable for
load-bearing applications, so inert biomaterials are proposed. However, the
surface must be modified through techniques such as coating with bioactive
materials, roughness and sized pores. The aim of this research was to
validate an approach for the evaluation of the tissue growth on implants of
porous alumina coated with bioactive materials.
Methods
Porous alumina implants were coated with 45S5 Bioglass® (BG) and
hydroxyapatite (HA) and implanted in rat tibiae for a period of 28 days. Ex
vivo resections were performed to analyze osseointegration, along with
histological analysis, Scanning Electron Microscopy with Energy Dispersive
X-Ray spectroscopy (SEM-EDX) line scanning, radiography and biomechanical
testing.
Results
Given that the process of implant integration needs with the bone tissue to
be accelerated, it was then seen that BG acted to start the rapid
integration, and HA acted to sustaining the process.
Conclusions
Inert materials coated with bioglass and HA present a potential for
application as bone substitutes, preferably with pores of diameters between
100 μm and 400 μm and, restrict for smaller than 100 μm, because it prevents
pores without organized tissue formation or vacant. Designed as functional
gradient material, stand out for applications in bone tissue under load,
where, being the porous surface responsible for the osseointegration and the
inner material to bear and to transmit the loads.