There are basically two categories of prison abuse: conduct which is sanctioned by express policy and misconduct that violates policy. The use of dogs to assist in cell extractions is an example of the former. As such, it is also is easy to eradicate a mere stroke of the pen can suffice.
The goal of protecting staff or deterring inmate misconduct cannot justify the use of dogs to terrorize and even bite prisoners. Security and control can be maintained while treating inmates at all times, and in all circumstances, decently, humanely, and justly.