I Want to become a Pediatric Dentist... What do you think the best major would be?

I know the best way to go is Biology, however, I would like to major in something that I would be able to fall back on and be in the health care field in the event that I don't get accepted to medical school. Please Help! By the way, I am about to be a Sopre in college in the fall, so this is a very important issue.. thanks