Biomedical Engineering Reference
In-Depth Information
Fig. 3. Regenerative medicine is based on “intelligent” biomaterials able.
dissuade surgeons at the crucial moment of implant. In addition, other variants have been
added, making the subject a spiny one. For example, on one hand, the porosity or fibrillar
form of these materials not only alters their biostability but also their mechanical
characteristics, which are today believed to be essential for implant success. On the other
hand, the variability of clinical applications, which may differentiate the desired
characteristics of each type of material, requires reflection.
There are many gaps in the examined articles. The first problem, already examined by many
authors, is variability in animal models, which hinders direct comparison of results.
Homogeneous studies on mechanical studies are also lacking, since so many of them focus
on tensile strength, and neglect compliance, which is an essential feature of vessels.
An effective model of an artificial vessel is very far from being achieved, and its
development must take into account the context in which it could be applied. Experimental
models have already been super-ceded, if we think that the application of a bio-absorbable
prosthesis means that cells must be able to reconstruct a new artery and that, in clinical
practice, this must be achieved in already damaged arteries.
In elective vascular surgery (e.g., arterial insufficiency in the lower limbs), cellularised
replacements are possible, tailored to suit single patients according to their tissue biopsy.
However, the procedures are time-consuming and very expensive, requiring dedicated
laboratories able to guarantee sterility and suitability for in vivo re-implantation of cell
cultures.
As regards urgent procedures, such as revascularisation of all types, the cell culture step
should be avoided. The ideal choice would be ready-to-use materials (Figure 3).
