Army Reserve GP to residency

I have a friend who is a GP in the Army Reserve. He is applying for a pediatric dentistry residency position on his own accord. I know that's a no no for AD as you have to go through DUINS (in Navy). I don't know what it's called in the Army. Is he going to be ok? Does Reserve not really care? As a pediatric dentist, will he be able to maintain his credentials and stay as a general dentist working for the Reserve after residency?
Source: Student Doctor Network - Category: Universities & Medical Training Authors: Source Type: forums