What is the ruling on photographing cadavers for study purposes when the photography was done without the knowledge of the doctors, even though it was previously permitted, and the student who took the pictures is not part of the group?

The bodies of the deceased have a specific sanctity and حرمة (inviolability) that must be observed according to Islamic law. The interest of study does not permit infringing upon this sanctity by photographing them, as such images are often available, and can be provided by instructors, or an alternative can be found when needed.