But I don't think you can reapply after having couple years in dental school. I recalled that in the application they ask whether you are matriculated in dental school or not. I heard that it is very difficult (or impossible) to reapply as year one into another school. In case, you dropped out and decide that you want to come back, you probably can reapply to the same school. Readmittance depends how you did when you was there, and how the admission committee likes you.
Good luck, dude.