One of the main problems is the transmission of disease. An infected allograft can transfer the infection to the surgical site. The result can be a failed graft or even death from septic shock.
Today's handling of donor tissue has reduced many of these problems. The tissue is screened first for infections and then sterilized. The screening step can detect HIV, hepatitis, and syphilis.
Other possible problems with allograft material include delayed graft healing and an allergic response to the donor tissue. The plus side of donor bank tissue is the lack of donor site trauma.