Im a Canadian at Penn Dental. The earliest you can challenge the Canadian Dental Boards is 3 months before your anticipated graduation. The latest is, I believe, 2-3 years after you graduate from dental school.
The Canadian dental boards are only offered 4 times / year. early-March, late-May, mid-November. So, you would be able to take the Candian dental boards in early-March of your senior year at dental school. That is when most of us Canadians at Penn Dental take it.
This site has all the information you need:
http://www.ndeb.ca/accredited/dates-locations
If you take the Canadian dental boards, and graduate from a dental school that means the canadian accreditation standards (NYU, and all other USA dental schools do), then those are the only things you must do. Then they'll do some background checks, criminal history, etc. And you can get licensed in ontario!
Here is the site for licensure in Ontario:
http://www.rcdso.org/BecomeADentistInOntario/RegistrationProcess/Requirements
Good luck fellow Canuck!
