JRogoff is right, you need to get into dental school first. Everyone has their own reasons for going into dentistry, no one reason is more noble than the other, but there are a few things every newly accepted dental student has to accept:
1) You have to like teeth & the oral cavity. If you can't stand teeth, you will be miserable b/c part of our training is to learn about every nook & cranny of all 32 adult & 20 deciduous teeth in minute detail. No joke here. There is no way around this one to survive dental school.
2) You have to entertain the idea of liking general dentistry. Even if you get into a specialty program right out of school, you are going to dental school to train to be a general dentist, and for 2 years (3 at some schools) you will be treating patients in every discipline of general dentistry. You can't pick and choose your cases b/c you won't graduate if you don't meet all your requirements across all the disciplines (specialties/departments) in dental school. And plans to specialize don't always go as you might expect. In my case, for example, I had the stats but didn't get into my specialty of choice right after graduation for some reason. I will be doing general dentistry for the upcoming year and that is fine with me, b/c being a general dentist is quite an accomplishment and nothing to look down upon. Those guys are your main referral source if you are a specialist, you have to treat your general dentists well!
3) As balanced as you want your life to be, you will have to make some sacrifices at some point of your 4 years to make it through. Every student sacrifices in different ways, but it will not be strictly 9 - 5; labwork and study time is expected to come out of the hours outside of 9 - 5.
To answer your questions...
The difference b/w the 4 vs. 6 year oral surgery program is simple. The 6 year program integrates the 3rd & 4th years of a MD curriculum to award an MD degree in addition to the oral surgery certificate. The 4 year program leads only to the certificate, no MD degree is earned. Dentally, they are both trained to do the same procedures, however, the scope of practice might be broadened in some states if you have the MD (hospital privileges and things like that).
DAT vs. MCAT - there have been a few threads about this in this forum not too long ago. Run a search.
Specializing - depends on what specialty you want. Some specialties like endo & prostho are hesitant to taking people straight out of school b/c they want their residents to have work experience in those disciplines (either in a private practice or in a General Practice Residency - aka GPR - program) so they know they are making a sound choice in choosing that specialty. Some are number driven - Ortho is notorious for this. If you graduate at the bottom of your class, there is very little you can do for your chances of getting in besides being the offspring of the program director. Ortho is all about the numbers first, experience/interests second. Oral Surgery is fairly numbers driven as well, but there is a little more wiggle room than Ortho IMO. Especially if you take a year or two and do an oral surgery based GPR or oral surgery fellowship to demonstrate a true interest in the specialty. But you still have to have somewhat competitive numbers to get a look even with the added experience. Endo has recently become very competitive and is now also numbers driven, but there are many endo programs that won't even look at your application unless you have real world experience after dental school, even if you are #1 in your class. Pedo is also getting popular, but personality is very important for this specialty given the age group you will be working with. For more info on the match and stuff, go check out this thread in the dental forum:
2004 Match Results Thread
So the bottom line of what we're trying to say is you have no idea if you will be #1 or #85 in your class till you get accepted and go through your first year. And whether or not you will specialize will be determined by your class record, board scores, and interest in the specialty. The majority of dental students don't specialize b/c it's cool or it will make them a more prestigious practitioner; they do it b/c they have a demonstrated interest in limiting their practice of dentistry to that one specialty only.
We're not trying to discourage you, only encourage you to fully consider dentistry before making the commitment.
