text: how long do people need to go to school to become an othodontist? im interested in othodontistry and wondering how many years of pre-dental and dental school is needed to become an othodontist.   thanks. 4 years of college (some dental schools will let you in with 3 years, but this is unusual). 4 years of dental school (this may vary) 2-3 years additional training to become an orthodontist.