As far as what I have been able to glean from minimum requirements of schools a baseline minimum is somewhere around a 2.75, but the majority of SDNers that usually comment on the subject say don't even think about applying until you have above a 3.0 overall and science GPA.
My advice:
1. Plan out your courses, and don't apply until you have above a 3.0 gpa.
2. I know you don't want to hear it but a huge amount of further effort will be required as you will have to do stellar on the DAT to make up for your lacking GPA.
3. Search your soul and decide right now if you have the desire to do it because it will take a lot of work and unless you are willing to give your all your chances look pretty grim.
4. As you probably know Dental schools look at all the school you have taken so make sure you average every class you have ever taken.
5. Post-bac programs are an excellent way to improve your GPA, especially if its a science based one you can kill 2 birds with one stone.
6. Extra-curriculars are crucial as well to well rounded application. Become a part of the honor society on your campus. Join some clubs and become active in them. Do tons of volunteer work and keep track of what you do. Aim now to have every single spot on the Professional Experience filled with meaningful experiences. Try to get a job in Dentistry, and if you can't find a paid spot call a free dental clinic and see if you can help them out.
On a happy note: I had a friend from my college that had like a 2.3 gpa from his first 4 year degree in Architecture. He hated it and decided to go back to school to be a Doctor. He literally got a 4.0 for the next 5 years while getting his chemistry bachelors and ended with an overall 3.3 GPA. He rocked the MCATs and is now accepted into a medical school.
The moral of the story is, anyone who takes this road cannot take it halfheartedly. You must give it your all. But if you do, I think that anything is possible.
Good luck on your journey.
