will it be hard to go into the army and become a Dental specialist or a Health care specialist?

i really want to go into the army and become either a dental specialist or health care specialist. those are my top two that i really want to go to, i do have other options though. so will it be hard on the ASVAB to make it into one of those MOS's?
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Getting the ASVAB scores for those jobs aren't a problem. Actually getting a slot for one of them is, since those jobs are highly sort out and we haven't had too many medical jobs open lately. If you're a junior in high school you have a much better chance of getting it since you'll get first dibs at jobs opening up in the summer of 2011 with the 14-month DEP. The 14-month DEP is only offered to kids in high school, graduates can't go past 12 months and usually ship within three to six months.
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