I'm not going to sugar coat this for you because you have to be real with yourself right now... that GPA does not even put you in a position to ask if you are competitive for highly rated schools. You are going to need a higher DAT score (23+) if you want to be competitive for middle/lower tier dental schools, and even then it will be tough. Can you get interviews with a 3.2/3.0/21? Yes. But is it likely? No.
I don't know if you're a junior or what, but I had a lousy GPA at the beginning of my junior year (it was actually lower at a 3.0/2.9). I realized then that there was no way I was going to be competitive even after one year of stellar grades, so I decided I was going to take a gap so I can factor in my grades from senior year. When all was said and done (after taking a ton of upper-level sciences) I finished with a 3.5/3.5. I then took my DAT following graduation. I received interviews and acceptances at a handful of schools, ones I wouldn't have even dreamed of receiving if I applied following junior year. Again, I don't know where you're at in your undergrad, but if you're a junior maybe try doing what I did.
Your EC's will obviously help, but stats are very important when it comes to landing an interview, and ultimately an acceptance.
