It is not something a person would be discharged over. It's akin to breaking an arm or something. You're just not fit for deployment at the time. I wonder what their requirements are for remedying this situation.
And... it's not a catch 22 MT. A catch 22 would be if they required him to have his tooth repaired, but couldn't release him to have the work done and couldn't do the work themselves because it happened when he wasn't AD.
MiniD