Yeah, change your personal statement. What have you been doing since being rejected from every dental school? Have you been retaking classes to boost your GPA? If you have, talk about that. And get a LOR from one of those profs in classes you have taken since being rejected. They might be able to comment on your recent performance in one of their classes. They might elaborate upon how you being rejected has increased your drive toward dental school.
What did the schools tell you to do?