There isn't any school, private or public, who would award you a DDS within two years, MD or no MD.  There are too many dental-specific course requirements in dental school in their first two years...conjoint dental morphology, prophylaxis, fundamentals in operative dentistry (the most important and time consuming course in the freshman year), dental radiology, principles of occlusion, etc, etc, and all of those courses are in the first year!  Forget it bud.  You're going to have to make a choice: dental school then med school, or just med school.  If you want primary care, choose one or the other, but not both.  It doesn't do you any good. 
I really don't understand why you want both an MD and a DDS for primary care aspects. What kind of primary care aspects are your targeting that an MD and DDS will provide for you?  I'm really confused as to your interest in getting both when you don't want to do oral surgery, and you're not willing to commit the time necessary to getting both.