i am a dentist n want to go to US for post graduation.im appearing for my toefl and gre ..i will be doin a 1 n 1/2 yr para dental couse in orthodontics..wil i still hv to appear for USMLE examsz?? for post graduation?? can i appear directly for D.D.S after thse entrace exams..ie.; gre n toefl??