Oh boy, I disagree. My biggest piece of advice is go into Dental School being comfortable...knowing that you just may end up being a General Dentist.
Getting to the top of one's Dental Class is tough. Getting into the top 10 for Oral Surgery is near impossible unless you are A) Natural Genius in Hand Skills + Didactics, B) Really want it for the "sake" of specializing aka name/prestige (most of these guys drop out after realizing how incredibly difficult/time consuming it is) or C) Love it.
Usually a combination of all three gets you to the top, but even then, it MAY NOT be enough. Dental School is seriously a whole nother beast. The kids that are in your class are your equivalents. They are all Type A and all hard working. Some are all that PLUS a whole tier smarter then you just because they are natural geniuses. Even if you try your hardest and stay day in/day out of lab...you may never get to the top.
Who knows, maybe you are great at didactics, but hand skills is a whole nother story. Some people just are amazing while some have to stay day in/day out in lab and take hits in their didactic scores while barely struggling to pass lab courses.
You SHOULD go into dental school with the positive attitude of being a gen. dent. If you go in with the mindset of ONLY oral surgery/specialty and nothing more (aka look down on general dent), then most likely prepare to be disappointed and humbled by your peers.
I guess to draw a correlation to the whole specialty thing...Just imagine it's basketball. Everyone in the NBA wants to be like Mike or Lebron, but not everyone can. You have your basketball players who are more gifted, who perhaps work harder, or perhaps want it more. Everyone tries so hard with a combination of all three talents, but in the end, its not meant to be. They just end up as regular basketball players making a decent living and not being the superstar they dream to be. That's Dental School...hell, that's life.