Deadline date is 15 Feb for classes starting in july. Requirements for international dentists are nbde part 1 or GRE and toefl.
Masters in oral biology is more research oriented. And masters in other dental subjects is clinically oriented. They are two years program. Or if you can complete 36 credits in less than two years then Ithe would one year to one and half year. I think every information is in the link given.