"When a matrix or scaffold containing cells is implanted into a patient to treat large bone defects or complex organ damage, it is difficult to ensure that the implanted tissue construct has sufficient vascular access," says Technical Insights Analyst Katherine Austin." A construct can be kept alive in a bioreactor by constantly supplying it with nutrients and oxygen, but once it is implanted in the patient, it has to be well supplied by capillaries. You have to have sufficient perfusion reaching all of the cells or they'll die."
Significant research is being carried out seeking means to overcome this barrier.
Desktop organ printing based on several 3D computer aided design (CAD) processes that can 'print' tissues layer by layer is another method being tested. The components of blood vessels are laid down within the various layers and the tissue constructs grow their own capillaries when the appropriate growth factors and cells are added.
Apart from this physiological issue, another major factor that hinders acceptance of breakthrough technologies of tissue engineering as standards of practice is the reluctance of the medical community to accept them.
Physicians and surgeons are often traditionalists, and unless they approve of and use them, the products are unlikely to succeed. In fact, lack of confidence among surgeons and inadequate marketing strategies have led several products from prominent companies to fail.