Biomedical Engineering Reference
In-Depth Information
Regardless of their clinical outcome, these pioneering studies were
fundamental in setting the main features required in tissue engineering.
these features are still pursued to optimise tissue engineering constructs for
different clinical applications. the main components of a tissue engineering
construct have been identified and are now widely recognised as indispensable
to successful clinical applications. these main constituents and their roles
have been presented by the Pittsburgh tissue Engineering initiative and by
the american niH as:
1.
Biomaterials
that can direct the adhesion, proliferation and differentiation
of cells to produce tissue with the histological properties of the tissue
that needs to be repaired.
2.
Cells
that can be reproducibly
i. isolated either from the same patient (autologous cells) or from a
human donor (allogeneic cells) or from an animal source (xenogeneic
cells)
ii. cultured
in vitro
either without losing their original characteristics,
as in the case of differentiated cells, or by acquiring the appropriate
phenotype as in the case of stem cells.
3.
Biomolecules
such as growth factors, drugs and genes which can stimulate
the cells to proliferate and differentiate.
4.
Engineering
that can provide solutions for optimised tissue growth
conditions (optimal scaffold morphology and bioreactors) as well as for
storage and shipping (packaging suitable for biological materials).
this chapter will present the state-of-the-art of bone tissue engineering
by critically assessing the progress made by scientists and industry towards
the optimisation of these main four components. the present and future
impact of combined multi-disciplinary efforts in clinical practice will be
also discussed by using typical examples of clinical applications where bone
repair is pursued.
Currently, the success of the surgical procedures for complete bone repair
which are not based on the use of permanent artificial implants relies on
the use of bone grafts. these are obtained from a different anatomic site of
the same patient (e.g. iliac crest) and are considered the gold standard for
bone repair in applications such as maxillofacial surgery. However, their
use leads to patient's morbidity and discomfort and to surgical procedures
relatively more convolute and expensive; two surgical teams have to operate
simultaneously on the patient to harvest the graft and to implant it at the site
of tissue damage.
