How to get the dental job in the military?

Hi, I've been trying for the longest time to enlist in the military. The job that i want, and the only job i want is Dental. I've gone to the Navy recruiters and the Air Force recruiters and Army recruiters and they all tell me the same thing (this branch is the only one that guarantees to give you the job you want). I've already wasted my chances in the Navy and Air Force. I dropped out of Navy DEP because i was given a rescue swimmer job and not a dental job. Then i dropped out of AFDEP because i was given a security forces job and not a dental job. I already have plenty of college credits going toward a dental career. The fact is that i don't want to waist my time in another job i don't want. So my question is, Is there anyway i can get the army recruiter, who is my last shot, to get me that dental job in the military? any suggestions, any get arounds, any tips will be helpful.