Biomedical Engineering Reference
In-Depth Information
engineering is focused on developing single tissues, as well as hybrid
organs and interfaces. Understanding the interaction between
molecules of the extracellular matrix and attached cells to the
materials is essential for proper biomaterial design. Applications of
biomaterials need experimental veriications in different laboratory
models to prove their functional effectiveness [1]. In addition to
the physical, chemical, mechanical, and biological performance,
the clinical performance of the material is also reviewed through
different trials.
Obtaining the same chemical structures as those of the body
tissues, however, does not solve the problem that the artiicially
obtained material is non-vital. For example, new structures of
materials incorporating sensory systems and signal processing are
proposed for the next generation of prostheses. They will help better
tailor the response in stiffness and damping equipment or provide
spectral properties closer to those of natural materials and living.
In the rehabilitation of the oral tissues, the fundamental role is
played by osseointegration, due to its excellent results and great
diversity of planning in the dental clinic. Osseointegration means
a direct connection between bone and implant without interposed
soft tissues layers [5]. However, 100% connection of the bone to
the implant material does not occur. Therefore, a more suitable
approach to understanding this term would be based on stability and
not histological criteria: “A process whereby clinically asymptomatic
rigid ixation of alloplastic materials is achieved, and maintained, in
bone during functional loading” [15].
Although modern implants have improved substantially over
the last 50 years, the general concept has remained unchanged:
replacing a missing tooth with an inert non-biological material.
It can be metal, ceramic, or combination of both. The rate of
technological improvements in implants has reached a plateau and
new developments will require major changes to the basic approach.
The recent researches focused on developing new materials,
designs, and the introduction of new surfaces, although not all those
tendencies were without pitfalls. For example, the ceramic-coated
metal implants turned out to be not so successful in the clinical trial
due to the brittle coating, which tends to lake away.
A great number of investigations are focused on implantology,
but they should be considered with great caution although basic
research is needed to search for new materials and designs.
In
vitro
studies bring into our knowledge many interesting indings;
