I think one of the requirements for the navy is that you have to have your bikini line waxed from time to time. Because of that, I joined the army instead.
Kidding aside, krmower gives the best advice. On top of that, talk to as *many* navy and army dentists you can to get their input. Especially get the input of the dentists who *hate* the military and see if their gripes are legit or not, and cross check that with people you trust. That way you can weed out the good info from the bad.