dentalman . . .
Foreign trained dentists dont get to bypass the first two years at just any dental school. Certain schools offer International Dentist Degree Programs that are designed for dentists trained outside the US. Students go through a two year course of study after which they receive a DDS degree. These programs have their own specific application process, and only accept a few students each year. Foreign dentists arent applying through AADSAS, theyre applying directly to schools that have this program.
OMFS is a specialty. In order to be eligible to apply for the OMFS program, you have to have completed a dental degree. There are other requirements as well but they differ depending on the school. For example, some also require a certain score on the National Dental Board Examination.
I imagine that its a very few select schools that offer MD/DDS type programs. They probably have their own specific application requirements. Youd have to do research to find out what schools have an accelerated or advanced program. But most dental schools dont offer anything of the sort, so for those applying to dentistry in general . . . theyre going through AADSAS.